Hello,
so Stew Perry contest is ended...
I spent all the nite from 19Z-04Z on the key and there is my short notice from this event.
In fact for me it was never the contest but more like friends party. I have small antenna at the fixed QTH and low power available only. This year I had not external RX antenna in good shape so my station performance was not high. So I did not expected so much and I wanted to meet friends on the air and send them best wishes HNY in the end of the year.
What I realized this year as an interesting thinks during the SP?
1. I made quite lot of friends from DL. Well I am close to the DL land so it is not so unique maybe but compare to last years I found really lot of them. Very good!
2. In opposite with evenings before the SP where I heard several JAs and AS stations I did not heard or found ANY JA or UA9,0 in the SP. Well I know that they were here and my bd setup did not allowed me to hear them maybe. OK, but at least JA7NI, HL1IVL and some few other good friends I expected :( Very bad!
3. The same situation was in my area with VK/ZL. I really looked for VK6VZ, VK2BJ, ZL3IX and I was really disappointed that I did not catch beeps from Oceania and even I did not hear the pile-up for them around known QRGs (28.5) Very bad!
4. Last interesting think was condx to NA in the second half of the nite. I expected that US sigs will come up after 02Z and will building until my SR. I really noticed first US friends around 02Z. The first readable signal came from Krassy, K1LZ. After I found on the band few another sigs from Charles, K3WW then John, WF2W and Barry, N1EU.
After them around 02:20Z when the condx peaked over here I found also several others but most of them were noticeable but I did not copy. I worked K1LZ, K3WW, WF2W and I tried to catch Barry as his signal built up to S7 here around 02:25Z but no luck. My small pistol barefoot station and low profile loaded half sloper at 11m was not enough to go over sea.
"The best signal" winner this event is John, WF2W who peaked over here around 02:15Z with 599 even on TX antenna! Congrats John!
The most surprising was the very quick drop of the condx after 02:30Z. All signals from overseas went down and after 03Z I did not hear anybody from USA. I expected the second peak during my SR but NIL! No beeps from US stations at all until the daylight. Very bad.
OK I worked total 118Q and 3xUSA. It was fun for me even although I will not win any category or any plaque. Maybe I am candidate for "no RX antenna used" or "worst results EU" plaque this year, hi.
Did You experienced the similar behavior with conditions this year in SP?
73 - Petr, OK1RP
.../-.-
Tuesday, December 31, 2013
Friday, December 27, 2013
Delayed Christmas gift on 160m
Hello,
the current conditions on Topband are so beautiful that every nite from the early evenning You can hear lot of DX stations.
Just see over here what is going on the band every nite
http://dxsummit.fi/CustomFilter.aspx?customCount=50&customRange=1819
Unfortunatelly my antenna setup at fixed QTH in Kostice is really small so there is no space and mainly no high supports available for somethink serious for this band.
I have only base coil loaded half sloper with 11m apex and just single huge Al wire burried radial close to the house till now. The antenna efficiency must be pretty low and big loading coil at the feed point must be power killer for sure. I am still thinking about improvement but I am so lazy guy... uff.
So for most of the time I agreed that I will work just EU stations from Kostice and some time when conditions are a bit better I can work big guns from closest overseas parts. The most DXing time I have to spend into the country side where I have better setup.
Yesterday evenning I was very surprised when I found Kim, HL5IVL on the band and I heard him even on my TX antenna as my ext. RX loop and the second RX antenna low profile Inverted Z dipole were out of order because of my KD9SV saver was removed currently.
For the first time I did not want to call Kim as "it is definitely not possible to work him with my antenna" (I guessed) but when I realized that nobody is calling him then I decided to try!
Yes Kim replied for the first time and asked for OK1? So I repeated my call for few times and finally Kim copied me ok and gave me 449. I repeated my call again to be sure that Kim has my call correctly and I sent him his 579 report quickly. No callers, no QRM, no other issues were on the band at this magic moment - thank You to all for QRX on the frequency at that time! Kim confirmed me all of that and we finished QSO with short Xmas wishes.
Wow it sounds like I worked HL from my post stamp lot area with so bad setup and 100W only... Kim has to have really good ears and my delayed Xmas gift arrived on 26th Dec instead of 24th as usual, hi.
Thank You Kim for Your great evenning on Topband and for Your an excellent operator's skills. Also thank You Santa for nice gift!
My K3 setup:
NB: DSP/t3-5, IF WID3, NR: 1-3, NTCH: 560, AGC SLP:7, THR:4 AGC-F, BW:100Hz
73 - Petr, OK1RP
.../-.-
Tuesday, December 10, 2013
The receiving small loops comparison by Rick, N6RK
Hello,
Rick, N6RK posted on Topband reflector very interesting article about his small receiving loops comparison. With his kind permission I am posting it over here as I am sure that it can help to each others and it can be good starting point for own tests in our QTH's.
Here is post from Rick, N6RK:
For the second night of the ARRL contest, I set up
three receiving loops with a switch to compare them in real
time. A Pixel circular loop (10 foot perimeter) using the
30 dB Clifton Labs preamp that comes with it was the first
antenna. The second one was a square 20 foot perimeter
shielded loop as I described in the Sept./Oct. 2009 National
Contest Journal:
http://www.n6rk.com/loopantennas/NCJ_loop_antenna_N6RK.pdf
The third antenna was a square 40 foot version of the loop
in the NCJ article. No external preamp was used with the 20
and 40 foot loops. The receiver was a Yaesu FT-1000 with its
internal preamp turned on. All three loops were oriented
to null at 30 degrees azimuth on ground wave, which
minimizes the noise at this QTH.
After comparisons on dozens of stations in the contest,
the clear winner was the 40 foot loop. In general,
the noise levels of the Pixel and the 40 foot loop
were similar. However, the latter had 6 to 10 dB
more signal, resulting in a markedly improved S/N ratio.
There were numerous stations where a signal that was Q5
on the 40 foot loop was inaudible on the Pixel.
I ended up just leaving the switch on the 40 foot loop
for the balance of the contest. If I had to have only
one loop to use, it would be an easy decision to go with
the 40 foot one.
The 20 foot loop had signal levels comparable
to the Pixel, but the noise level was considerably lower.
It came in 2nd place. The signal level of the 20 foot
loop has always been marginal for the FT-1000 without
external preamp. It might help to have some preamplification
on it. I would rather use a larger loop than fool with
a preamp. We have strong BCB signals, including one at
1,700 kHz, so preamps are always problematical.
The 40 foot loop will work (on 160 meters only) with an
unmodified antenna circuit board, however, I ran into
BCB QRM of the tuning diodes. I removed one of the two
tuning diodes, which allowed the tuning voltage to rise.
This helped on the BCB QRM, but there was still some lite
hash heard. Finally, I went to four diodes in a series
parallel configuration as described in the article. This
fixed the BCB QRM. The final configuration tunes from
about 1.25 to 2.5 MHz, covering WWV.
I also compared to the transmit vertical. In most cases,
stations could be copied on the vertical, but maybe not
at 100%, and even when they could be copied, there was
the usual unpleasant impulsive noise, as compared to the
gentle rushing noise of the loops. From a listening
fatigue aspect, it is not good to have to listen on the
vertical. I have no technical theory to explain why
this is, I just observe it consistently.
The Pixel loop covers all the way to 30 MHz. It still
may be a useful receive antenna on the higher bands.
When I purchased it for evaluation, I suspected that
160 meters was not its strong suit. Below 160 meters
on BCB, the signals are much stronger and the Pixel should
have no problem. Thus the take away is only that
the Pixel isn't very useful on 160 meters.
The mechanical construction of the 40 foot version is
much more difficult that the 20 foot version. My initial
attempt was successful enough for these tests, but was
basically a discovery of what NOT to do. It did become
clear that it is much easier to guy the vertical support
rather than making it self supporting. I am interested
in hearing about successful large loop construction
techniques.
Rick, N6RK
As I have the coaxial loops in two versions > K9FD and N6RK design and finally I arranged also the Mini Diamond wire loop designed by Pete, W2PM I am interesting a lot in the results of comparisons on my really small "post stamp" lot.
So I am going to try to make similar tests and we will see the differences.
73 - Petr, OK1RP
.../-.-
Rick, N6RK posted on Topband reflector very interesting article about his small receiving loops comparison. With his kind permission I am posting it over here as I am sure that it can help to each others and it can be good starting point for own tests in our QTH's.
Here is post from Rick, N6RK:
For the second night of the ARRL contest, I set up
three receiving loops with a switch to compare them in real
time. A Pixel circular loop (10 foot perimeter) using the
30 dB Clifton Labs preamp that comes with it was the first
antenna. The second one was a square 20 foot perimeter
shielded loop as I described in the Sept./Oct. 2009 National
Contest Journal:
http://www.n6rk.com/loopantennas/NCJ_loop_antenna_N6RK.pdf
The third antenna was a square 40 foot version of the loop
in the NCJ article. No external preamp was used with the 20
and 40 foot loops. The receiver was a Yaesu FT-1000 with its
internal preamp turned on. All three loops were oriented
to null at 30 degrees azimuth on ground wave, which
minimizes the noise at this QTH.
After comparisons on dozens of stations in the contest,
the clear winner was the 40 foot loop. In general,
the noise levels of the Pixel and the 40 foot loop
were similar. However, the latter had 6 to 10 dB
more signal, resulting in a markedly improved S/N ratio.
There were numerous stations where a signal that was Q5
on the 40 foot loop was inaudible on the Pixel.
I ended up just leaving the switch on the 40 foot loop
for the balance of the contest. If I had to have only
one loop to use, it would be an easy decision to go with
the 40 foot one.
The 20 foot loop had signal levels comparable
to the Pixel, but the noise level was considerably lower.
It came in 2nd place. The signal level of the 20 foot
loop has always been marginal for the FT-1000 without
external preamp. It might help to have some preamplification
on it. I would rather use a larger loop than fool with
a preamp. We have strong BCB signals, including one at
1,700 kHz, so preamps are always problematical.
The 40 foot loop will work (on 160 meters only) with an
unmodified antenna circuit board, however, I ran into
BCB QRM of the tuning diodes. I removed one of the two
tuning diodes, which allowed the tuning voltage to rise.
This helped on the BCB QRM, but there was still some lite
hash heard. Finally, I went to four diodes in a series
parallel configuration as described in the article. This
fixed the BCB QRM. The final configuration tunes from
about 1.25 to 2.5 MHz, covering WWV.
I also compared to the transmit vertical. In most cases,
stations could be copied on the vertical, but maybe not
at 100%, and even when they could be copied, there was
the usual unpleasant impulsive noise, as compared to the
gentle rushing noise of the loops. From a listening
fatigue aspect, it is not good to have to listen on the
vertical. I have no technical theory to explain why
this is, I just observe it consistently.
The Pixel loop covers all the way to 30 MHz. It still
may be a useful receive antenna on the higher bands.
When I purchased it for evaluation, I suspected that
160 meters was not its strong suit. Below 160 meters
on BCB, the signals are much stronger and the Pixel should
have no problem. Thus the take away is only that
the Pixel isn't very useful on 160 meters.
The mechanical construction of the 40 foot version is
much more difficult that the 20 foot version. My initial
attempt was successful enough for these tests, but was
basically a discovery of what NOT to do. It did become
clear that it is much easier to guy the vertical support
rather than making it self supporting. I am interested
in hearing about successful large loop construction
techniques.
Rick, N6RK
As I have the coaxial loops in two versions > K9FD and N6RK design and finally I arranged also the Mini Diamond wire loop designed by Pete, W2PM I am interesting a lot in the results of comparisons on my really small "post stamp" lot.
So I am going to try to make similar tests and we will see the differences.
73 - Petr, OK1RP
.../-.-
Friday, November 29, 2013
Base loaded half sloper - part I.
Hello all Topbanders,
it's really long time ago when I posted the last article. I would like to send my appologize to all of You. I hope that I will be able to update this place more often...
In preview articles "Antennas inspiration"we talked about different antennas suitable for small pocket size lots. In fact I am still looking for some of that also as my fixed QTH is so small that I have no more than 10m x 15m garden available and just 6m high roof. No tower, no trees around.
Some time ago I found interesting article about shortened half sloper writen by Don, WD8DSB. There is what I found as the first on the internet about this type of the antenna:
Rugged 160 Meter sloper...
Our best selling antenna is our 160 meter, ruggedized version of our popular "half-sloper". We have been building these antennas for over 12 years. They work and work well.
It's features heavier, 14 awg insulated wire, a built-in SO239 connector and a solid cover over the coil. Ideal for 100-150 watt radios, this antenna solves the problems of working "top-band" and eliminates the need for a tuner. Trimmed to resonance at your favorite spot in the band this antenna offers omni-directional performance with minimum effort.
We start with a tightly wound 14 awg insulated wire coil.
This is the finished antenna, ready to be hung on your tower.
The radiator wire will be left several feet long to allow you to "prune" it to the length that tunes it to the exact spot in the band that you need. Once tuned near the center of the band at your location the antenna will cover the entire band without any retuning or tinkering. Note: this antenna can withstand quite a bit of power but we have NOT tested it above 150 watts. We don't build "high-power" antennas. We build antennas that give you that extra performance.
This antenna ships 75' in length and will be trimmed back to 68' or less on installation. It works best when attached to your tower at about the 45-50' level. This allows the wire to be angled down to the ground at a comfortable angle (somewhere near 45 degrees) and attached to a suitable support 8 or 9 feet off the ground ( to keep someone from touching it while you are transmitting) 45' or so away from your tower.
We have had one of these on our tower for 12 years with no problems.
We have made several improvements to the design over the years. The one shown here is a very early production model. (12 years in use...)
73 de Stan, KC5UYF
OK, it sounds good. What is important is that the installation need to have grounding point and some pipes or way to simulate the vertical part of the half sloper going to ground or better to the radials system.
The minimal height seems to be around 8-10m. Of course not for DXing but to come to TB in general. I am going to thinking about that...and need to find the original post from Don, WD8DSB.
73 - Petr, OK1RP
.../-.-
it's really long time ago when I posted the last article. I would like to send my appologize to all of You. I hope that I will be able to update this place more often...
In preview articles "Antennas inspiration"we talked about different antennas suitable for small pocket size lots. In fact I am still looking for some of that also as my fixed QTH is so small that I have no more than 10m x 15m garden available and just 6m high roof. No tower, no trees around.
Some time ago I found interesting article about shortened half sloper writen by Don, WD8DSB. There is what I found as the first on the internet about this type of the antenna:
Rugged 160 Meter sloper...
Our best selling antenna is our 160 meter, ruggedized version of our popular "half-sloper". We have been building these antennas for over 12 years. They work and work well.
It's features heavier, 14 awg insulated wire, a built-in SO239 connector and a solid cover over the coil. Ideal for 100-150 watt radios, this antenna solves the problems of working "top-band" and eliminates the need for a tuner. Trimmed to resonance at your favorite spot in the band this antenna offers omni-directional performance with minimum effort.
We start with a tightly wound 14 awg insulated wire coil.
This is the finished antenna, ready to be hung on your tower.
The radiator wire will be left several feet long to allow you to "prune" it to the length that tunes it to the exact spot in the band that you need. Once tuned near the center of the band at your location the antenna will cover the entire band without any retuning or tinkering. Note: this antenna can withstand quite a bit of power but we have NOT tested it above 150 watts. We don't build "high-power" antennas. We build antennas that give you that extra performance.
This antenna ships 75' in length and will be trimmed back to 68' or less on installation. It works best when attached to your tower at about the 45-50' level. This allows the wire to be angled down to the ground at a comfortable angle (somewhere near 45 degrees) and attached to a suitable support 8 or 9 feet off the ground ( to keep someone from touching it while you are transmitting) 45' or so away from your tower.
We have had one of these on our tower for 12 years with no problems.
We have made several improvements to the design over the years. The one shown here is a very early production model. (12 years in use...)
73 de Stan, KC5UYF
OK, it sounds good. What is important is that the installation need to have grounding point and some pipes or way to simulate the vertical part of the half sloper going to ground or better to the radials system.
The minimal height seems to be around 8-10m. Of course not for DXing but to come to TB in general. I am going to thinking about that...and need to find the original post from Don, WD8DSB.
73 - Petr, OK1RP
.../-.-
Crappy Chinese cables in Your shack by Alan, N5NA
Watch Out for Crappy Chinese Cables!
At the beginning of the ARRL 10M Contest a couple of weeks ago I noticed several "squalling" noises across the band. I had heard these before but hadn't investigated. I thought it was probably from the Ethernet cabling in my house I decided to see if I could do something about it.
First I disconnected the coax from my rig, the noise disappeared. I reconnected the coax and turned off my router and wireless internet radio. The noise was still there. Next I disconnected the coax from the remote sensor for my SWR meter. The noise was still there. Hmmm, that's strange. I disconnected the coax from the antenna from the back of my amp. The noise was still there. Next I disconnected the jumper from my rig from the back of the amp. The noise was still there. At this point the only thing connected to my rig was a 6' coax jumper. I disconnected it and the noise disappeared!
That coax jumper was factory assembled with molded strain relief at the PL-259's. I replaced that cable with a homemade cable and the noise stayed gone.
I cut open the factory cable and found the coax had maybe 10% coverage, if you could call it coverage. It was junk. If I'm not mistaken I bought that cable from one of the large dealers at Hamcom. Below are a couple of pictures. It looks pretty until you cut it open.
A few months ago I was getting ready for the Texas QSO Party. I was testing a USB>Serial adapter that uses a separate USB cable. When I connected the adapter there was a noticeable noise increase in my Elecraft K3. Again, I tracked that noise down to the USB cable, which was a piece of junk from China. After replacing the USB cable with a Belden cable I didn't hear any noise from the adapter.
Moral of the story, beware of crappy cables from China!
73 - de Alan, N5NA.
---
Inspired by Alan and his article I started to check all of my coaxial cables in the shack. Well because of tons of cables over here it's not the "one evening project" but some strange results are available even now...
I found that after changing some of the cables for high quality one I noticed the SWR changes on LF/HF bands and also I noticed some noise improvement. It not solved my noise issue completely of course but even just noticable changes in the noise level seems that cables was not good and put me in troubles with weak signal reception over here.
I am going to check all of my cables !
73 - Petr, OK1RP
.../-.-
At the beginning of the ARRL 10M Contest a couple of weeks ago I noticed several "squalling" noises across the band. I had heard these before but hadn't investigated. I thought it was probably from the Ethernet cabling in my house I decided to see if I could do something about it.
First I disconnected the coax from my rig, the noise disappeared. I reconnected the coax and turned off my router and wireless internet radio. The noise was still there. Next I disconnected the coax from the remote sensor for my SWR meter. The noise was still there. Hmmm, that's strange. I disconnected the coax from the antenna from the back of my amp. The noise was still there. Next I disconnected the jumper from my rig from the back of the amp. The noise was still there. At this point the only thing connected to my rig was a 6' coax jumper. I disconnected it and the noise disappeared!
That coax jumper was factory assembled with molded strain relief at the PL-259's. I replaced that cable with a homemade cable and the noise stayed gone.
I cut open the factory cable and found the coax had maybe 10% coverage, if you could call it coverage. It was junk. If I'm not mistaken I bought that cable from one of the large dealers at Hamcom. Below are a couple of pictures. It looks pretty until you cut it open.
A few months ago I was getting ready for the Texas QSO Party. I was testing a USB>Serial adapter that uses a separate USB cable. When I connected the adapter there was a noticeable noise increase in my Elecraft K3. Again, I tracked that noise down to the USB cable, which was a piece of junk from China. After replacing the USB cable with a Belden cable I didn't hear any noise from the adapter.
Moral of the story, beware of crappy cables from China!
73 - de Alan, N5NA.
---
Inspired by Alan and his article I started to check all of my coaxial cables in the shack. Well because of tons of cables over here it's not the "one evening project" but some strange results are available even now...
I found that after changing some of the cables for high quality one I noticed the SWR changes on LF/HF bands and also I noticed some noise improvement. It not solved my noise issue completely of course but even just noticable changes in the noise level seems that cables was not good and put me in troubles with weak signal reception over here.
I am going to check all of my cables !
73 - Petr, OK1RP
.../-.-
The 160M "No Excuses" Homebrew Vertical by John, K6MM
Hello,
some months ago I attended on the web seminar about the 160m antenna for limited space. Excellent presentation done by K6MM was named "No Excuses" homebrew vertical. I found this design very interesting so I am preparing some hardware and I will try to work on it in the summer time because my post stamp lot is quite similar to the John's one.
When I discussed about this antenna on few hamfests then I have got several emails about the antenna construction and I was asked for contact to John, K6MM etc.
So there I am posting the link to John, K6MM page where You can find all informations regarding his nice project.
I will be glad to get feedback over here about the performance in Your location.
73 - Petr, OK1RP
.../-.-
some months ago I attended on the web seminar about the 160m antenna for limited space. Excellent presentation done by K6MM was named "No Excuses" homebrew vertical. I found this design very interesting so I am preparing some hardware and I will try to work on it in the summer time because my post stamp lot is quite similar to the John's one.
When I discussed about this antenna on few hamfests then I have got several emails about the antenna construction and I was asked for contact to John, K6MM etc.
So there I am posting the link to John, K6MM page where You can find all informations regarding his nice project.
I will be glad to get feedback over here about the performance in Your location.
73 - Petr, OK1RP
.../-.-
Inverted L for restricted space...
Hello,
when I looked for more information about my antenna (base coil loaded half sloper) I found interesting antenna also for restricted space.
In fact the vertical part is helical vertical where 11.7m of insulated 2.5mmsq wire is wounded on the 5m of the fiber glass pole including the wire going to point A for feed line. The spacing for the winding is approx. 1.5cm.
The 2x 18.1m of the insulated wire used for radials on the ground is compromised solution for that installation. Definitely it's needed better grounding system and 16x 16m is recommended as minimum where 3dB loss is expected.
Well I did not tested it but for those who are space limited it can be inspiration for experiments.
Do not hesitate to share with us Your experiences with compromised antennas like this.
73 - Petr, OK1RP
.../-.-
when I looked for more information about my antenna (base coil loaded half sloper) I found interesting antenna also for restricted space.
In fact the vertical part is helical vertical where 11.7m of insulated 2.5mmsq wire is wounded on the 5m of the fiber glass pole including the wire going to point A for feed line. The spacing for the winding is approx. 1.5cm.
The 2x 18.1m of the insulated wire used for radials on the ground is compromised solution for that installation. Definitely it's needed better grounding system and 16x 16m is recommended as minimum where 3dB loss is expected.
Well I did not tested it but for those who are space limited it can be inspiration for experiments.
Do not hesitate to share with us Your experiences with compromised antennas like this.
73 - Petr, OK1RP
.../-.-
ZJ Beverages and how it works - part II.
Hello,
as I promised there I am posting the open discussion about the ZJ Beverages as I found it on the reflector.
TopBand: ZJ Beverage Box Comments and Update de W0AH
from [W0AH@aol.com] [Permanent Link][Original]
To: <topband@contesting.com>
Subject: TopBand: ZJ Beverage Box Comments and Update de W0AH
From: W0AH@aol.com (W0AH@aol.com)
Date: Wed, 5 Nov 1997 16:47:09 -0500 (EST)
On Oct. 22 I posted to the list that I was not happy about the performance of my NE beverage and also that my ZJ Beverage Box was not working and that I was going to try and fix it.
Several wrote and asked me to send them any information I received since
they also need ed to fix the ZJ beverage box. Therefore, this post.
First, I want to say that my ZJ beverage box worked fine when I first
installed it a couple of years ago. It brought my beverage signal up 2 or 3S-units as I recall. I had no intermod (I have no local commercial
stations). Using a coaxial hand switch between the transmitting antenna and the beverage (my transceiver had no separate receive antenna), I forgot to switch the antennas and ran power into the ZJ box.
I wrote ZJ, which a month later sent me a replacement device, gratis.
Now, over a year later, wanting too repair the ZJ box, I can not find the device he sent me. Thus my inquiry to the list recently.
My ZJ Box did not come with a schematic which is my main complaint.
Looking at the device, I thought it was a gasfet, but I have been informed by KM1H, W8JI, and K0CS that it is a MMIC. MMIC stands for Monolithic Microwave Integrated Circuit Amplifier. I have built several of the well regarded Down East Microwave kits (for 902, 1296, and 2304 MHz) which use MMICs. Both KM1H and W8JI wrote that the MMIC was a poor choice for a 1.8 MHz preamp. I agree that it is an odd choice, but my Avantek Semiconductor Data Book shows that the power gain and other MMIC specs are flat from about 0.1 to about 1 or 2 GHz, depending on the specific device. Also, the Avantek power gain versus frequency chart shows them being flat to DC! Therefore, the device should be suitable for 1.8 Mhz.
KM1H siad there had been a discussion of the ZJ Beverage Box which can
be found in the archives. So more information is available there. He also said that the ZJ Boxes had been shipped with "at least 4 different" MMICS including the MAR1, MAR3, and others. He stated that some of those devices needed different biasing. He also stated the ZJ Box was subject to overload and IMD. Carl said the "ultraminature 9:1 balun is just as bad." W8JI suggested replacing the MMIC with "a regular CATV transistor."
W4MPY wrote that his ZJ beverage box filled up with water and that he
has tried unsuccessfully to get help from ZJ.
Both W8JI and KM1H stated that a good beverage will not generally need
a preamplifier.
K0CS kindly sent me a MAR-3 device which had been supplied by ZJ as a
replacement device.
Looking at the various Avantek MMIC specs (I can not find my cross
reference to compare the Avantek MSA MMICs to the MAR MMICS) I see several MMICs with very similar specs (in some cases just different plastic packages-ie. cases). Almost all of them require 4.5 to 5.5 volts DC. I suspect the several different MMICs supplied in the ZJ boxes have identical specs at 1.8 MHz and that biasing is not an issue. For those who need to replace the MMIC, a MAR-1, MAR-3 or equivalent should work fine. MMICs are listed in several of my electronic catalogs for about a dollar each.
I hope the above is useful information and that some of you get your ZJ
beverage boxes back up and running. Unfortuately, mine still is not working after I replaced the MMIC. I suspect that the ultraminature balun, as KM1H described it, needs replacement. Not sure I want to proceed until I get a schematic. Does anyonwe have one? See also my next post on beverage transformers. Doug W0AH
TopBand: ZJ Beverage Box MAR3 MMIC Replacement?
from [km1h @ juno.com] [Permanent Link][Original]
To: <topband@contesting.com>
Subject: TopBand: ZJ Beverage Box MAR3 MMIC Replacement?
From: km1h@juno.com (km1h @ juno.com)
Date: Thu, 23 Oct 1997 18:58:41 EDT
On Thu, 23 Oct 1997 15:44:36 EDT W0AH <W0AH@aol.com> writes:
>Thanks K0CS for the info that the ZJ Beverage Box uses a MAR3 MMIC,
>which are quite inexpensive .
Wrong info Doug. Your ZJ "thing" has a MAR-1 in it according to ur
number. Owners have found at least 4 different MAR MMIC's so far. NOT interchangeable without changing bias resistor either.
As discussed here at length a month or so ago, the choice of device PLUS
the matching xfmr in the ZJ box makes it an all around poor choice for Beverages. Nice and cute toy but no good for real world use. Suggest you check the Archives for comments by users, W8JI, myself, etc.
73 Carl KM1H
I thought I had a MAR3 around here, but can't find it.
Can any of the following Avantek be substituted for the MAR3?
Avantek 0185, 0285, 0485, 0685?????
I'll post a message as to how this all turns out as others have contacted me concerning their non-working ZJ Beverage boxes.
I have the above. If no answer, I'll try to call WB5LUA, Mr. MMIC!
Doug W0AH
Well any other experiences with this system even negative are welcomed over there.
73 - Petr, OK1RP
.../-.-
as I promised there I am posting the open discussion about the ZJ Beverages as I found it on the reflector.
TopBand: ZJ Beverage Box Comments and Update de W0AH
from [W0AH@aol.com] [Permanent Link][Original]
To: <topband@contesting.com>
Subject: TopBand: ZJ Beverage Box Comments and Update de W0AH
From: W0AH@aol.com (W0AH@aol.com)
Date: Wed, 5 Nov 1997 16:47:09 -0500 (EST)
On Oct. 22 I posted to the list that I was not happy about the performance of my NE beverage and also that my ZJ Beverage Box was not working and that I was going to try and fix it.
Several wrote and asked me to send them any information I received since
they also need ed to fix the ZJ beverage box. Therefore, this post.
First, I want to say that my ZJ beverage box worked fine when I first
installed it a couple of years ago. It brought my beverage signal up 2 or 3S-units as I recall. I had no intermod (I have no local commercial
stations). Using a coaxial hand switch between the transmitting antenna and the beverage (my transceiver had no separate receive antenna), I forgot to switch the antennas and ran power into the ZJ box.
I wrote ZJ, which a month later sent me a replacement device, gratis.
Now, over a year later, wanting too repair the ZJ box, I can not find the device he sent me. Thus my inquiry to the list recently.
My ZJ Box did not come with a schematic which is my main complaint.
Looking at the device, I thought it was a gasfet, but I have been informed by KM1H, W8JI, and K0CS that it is a MMIC. MMIC stands for Monolithic Microwave Integrated Circuit Amplifier. I have built several of the well regarded Down East Microwave kits (for 902, 1296, and 2304 MHz) which use MMICs. Both KM1H and W8JI wrote that the MMIC was a poor choice for a 1.8 MHz preamp. I agree that it is an odd choice, but my Avantek Semiconductor Data Book shows that the power gain and other MMIC specs are flat from about 0.1 to about 1 or 2 GHz, depending on the specific device. Also, the Avantek power gain versus frequency chart shows them being flat to DC! Therefore, the device should be suitable for 1.8 Mhz.
KM1H siad there had been a discussion of the ZJ Beverage Box which can
be found in the archives. So more information is available there. He also said that the ZJ Boxes had been shipped with "at least 4 different" MMICS including the MAR1, MAR3, and others. He stated that some of those devices needed different biasing. He also stated the ZJ Box was subject to overload and IMD. Carl said the "ultraminature 9:1 balun is just as bad." W8JI suggested replacing the MMIC with "a regular CATV transistor."
W4MPY wrote that his ZJ beverage box filled up with water and that he
has tried unsuccessfully to get help from ZJ.
Both W8JI and KM1H stated that a good beverage will not generally need
a preamplifier.
K0CS kindly sent me a MAR-3 device which had been supplied by ZJ as a
replacement device.
Looking at the various Avantek MMIC specs (I can not find my cross
reference to compare the Avantek MSA MMICs to the MAR MMICS) I see several MMICs with very similar specs (in some cases just different plastic packages-ie. cases). Almost all of them require 4.5 to 5.5 volts DC. I suspect the several different MMICs supplied in the ZJ boxes have identical specs at 1.8 MHz and that biasing is not an issue. For those who need to replace the MMIC, a MAR-1, MAR-3 or equivalent should work fine. MMICs are listed in several of my electronic catalogs for about a dollar each.
I hope the above is useful information and that some of you get your ZJ
beverage boxes back up and running. Unfortuately, mine still is not working after I replaced the MMIC. I suspect that the ultraminature balun, as KM1H described it, needs replacement. Not sure I want to proceed until I get a schematic. Does anyonwe have one? See also my next post on beverage transformers. Doug W0AH
TopBand: ZJ Beverage Box MAR3 MMIC Replacement?
from [km1h @ juno.com] [Permanent Link][Original]
To: <topband@contesting.com>
Subject: TopBand: ZJ Beverage Box MAR3 MMIC Replacement?
From: km1h@juno.com (km1h @ juno.com)
Date: Thu, 23 Oct 1997 18:58:41 EDT
On Thu, 23 Oct 1997 15:44:36 EDT W0AH <W0AH@aol.com> writes:
>Thanks K0CS for the info that the ZJ Beverage Box uses a MAR3 MMIC,
>which are quite inexpensive .
Wrong info Doug. Your ZJ "thing" has a MAR-1 in it according to ur
number. Owners have found at least 4 different MAR MMIC's so far. NOT interchangeable without changing bias resistor either.
As discussed here at length a month or so ago, the choice of device PLUS
the matching xfmr in the ZJ box makes it an all around poor choice for Beverages. Nice and cute toy but no good for real world use. Suggest you check the Archives for comments by users, W8JI, myself, etc.
73 Carl KM1H
I thought I had a MAR3 around here, but can't find it.
Can any of the following Avantek be substituted for the MAR3?
Avantek 0185, 0285, 0485, 0685?????
I'll post a message as to how this all turns out as others have contacted me concerning their non-working ZJ Beverage boxes.
I have the above. If no answer, I'll try to call WB5LUA, Mr. MMIC!
Doug W0AH
Well any other experiences with this system even negative are welcomed over there.
73 - Petr, OK1RP
.../-.-
ZJ Beverages and how it works - part I.
Hello,
when I discussed some time ago about the Beverages and neccessary boxes I mentioned that one of my Beverage sets is W2ZJ system. After several emails received from some of You I decided to scan the user guide as it is not available on the internet.
I have not enough time to replying to each of You for questions about ZJ Beverage boxes...how it is designed and which parameters it has.
So there are all information I have and let's go to check it guys.
I am planing to install the ZJ boxes and test it as I heard a lot of negative reviews about it. On the other hands it's promissing the system with pre-amp on the Beverage side then sigs going to shack enough strong and filtered.
As I need the strong negotiation with neighbours to install the 164m of insulated wire on the 2m stands in country side I am not sure when I will be ready to test it.
Does anybody used ZJ Beverages and how it worked for You please?
73 - Petr, OK1RP
.../-.-
when I discussed some time ago about the Beverages and neccessary boxes I mentioned that one of my Beverage sets is W2ZJ system. After several emails received from some of You I decided to scan the user guide as it is not available on the internet.
I have not enough time to replying to each of You for questions about ZJ Beverage boxes...how it is designed and which parameters it has.
So there are all information I have and let's go to check it guys.
I am planing to install the ZJ boxes and test it as I heard a lot of negative reviews about it. On the other hands it's promissing the system with pre-amp on the Beverage side then sigs going to shack enough strong and filtered.
As I need the strong negotiation with neighbours to install the 164m of insulated wire on the 2m stands in country side I am not sure when I will be ready to test it.
Does anybody used ZJ Beverages and how it worked for You please?
73 - Petr, OK1RP
.../-.-
W2PM MiniDiamond RX loop by OK1RP - part I.
Hello,
as I am still looking for the receiving antenna which will allow me to improve the receiving performance on my pocket size QTH (250msq) I was very happy to get construction details and description of receiving loop with name MiniDiamond from Pete, W2PM. I have to say that Pete is real gentleman and he provided a lot of effort to help me with RX antennas. Pete helped me to understand how to build the very small loops effectively for 160m band.
So after some time I decided to start with building the MiniDiamond loop and as Pete said I am making it as large as possible. All will be posted here step by step according to the progress of building. You will see used hardware, construction, mounting process, measurement and testing of the final product as same as the on-air results. If the antenna will not work then You will be able to check where I made the fault and learn from it to avoid Your own issues.
Today I will show You few pictures from bulding the main cross support.
I decided to use bamboo as the main cross support because all the other materials seemed to me worse. Fiber glass poles are too breakable, plastic poles used quite often as potatoes support on the garden are too heavy and short as same as wooden poles. On the picture You can see the used tickness. The only problem was in the local store with finding few bamboo poles enough straight, hi.
As the mounting support I used universal plate from the local store. You can see a lot of holes in the plate...great as I did not need to make any hole just decide for right one with the screws.
The cross support is already done waiting for mounting the last wooden part which will be screwed on the rotor unit. I hope that it will fit to the old rotor used for light UHF antennas...
Finally You can see the box arrived by snail mail with non-inductive resistor and 900/50ohms transformer units all in nice water resistant plastic houses.
If You are interesting in this RX Loop kit then be noted that they are available for loops, Beverages and also Ewe antennas in different versions like BNC, F connectors etc.
That is all for now and see You soon with some progress with building the loop.
73 - Petr, OK1RP
.../-.-
as I am still looking for the receiving antenna which will allow me to improve the receiving performance on my pocket size QTH (250msq) I was very happy to get construction details and description of receiving loop with name MiniDiamond from Pete, W2PM. I have to say that Pete is real gentleman and he provided a lot of effort to help me with RX antennas. Pete helped me to understand how to build the very small loops effectively for 160m band.
So after some time I decided to start with building the MiniDiamond loop and as Pete said I am making it as large as possible. All will be posted here step by step according to the progress of building. You will see used hardware, construction, mounting process, measurement and testing of the final product as same as the on-air results. If the antenna will not work then You will be able to check where I made the fault and learn from it to avoid Your own issues.
Today I will show You few pictures from bulding the main cross support.
I decided to use bamboo as the main cross support because all the other materials seemed to me worse. Fiber glass poles are too breakable, plastic poles used quite often as potatoes support on the garden are too heavy and short as same as wooden poles. On the picture You can see the used tickness. The only problem was in the local store with finding few bamboo poles enough straight, hi.
As the mounting support I used universal plate from the local store. You can see a lot of holes in the plate...great as I did not need to make any hole just decide for right one with the screws.
The cross support is already done waiting for mounting the last wooden part which will be screwed on the rotor unit. I hope that it will fit to the old rotor used for light UHF antennas...
Finally You can see the box arrived by snail mail with non-inductive resistor and 900/50ohms transformer units all in nice water resistant plastic houses.
If You are interesting in this RX Loop kit then be noted that they are available for loops, Beverages and also Ewe antennas in different versions like BNC, F connectors etc.
That is all for now and see You soon with some progress with building the loop.
73 - Petr, OK1RP
.../-.-
Friday, November 15, 2013
MW stick vs. Half Sloper antenna receiving test by Petr, OK1RP - part I.
Hello,
when I spoke to several DXers about the Mini Whip stick all of them said "uhh, Petr if You are interesting in serious operation on TB then forget it and focus on good RX loops or so".
I do not like to evaluate or reprobate anything (specially antennas) without testing it first and mainly You never know which antenna and when will help you to hear weak signals on the TB so...I have this stick now and there is comparison with TX antenna > based coil loaded 11m high half sloper (see preview article about it)...
10/11/2010
22:45 160m W1MK S6/sloper S5/MW (better s/n on MW)
22:53 160m N3IR S3/sloper S2/MW (better s/n on MW)
23:20 160m VE1ZZ S5/sloper S4/MW (the same readability)
23:20 160m 9K2YM S6/sloper S5/MW (the same readability)
23:30 160m W8FJ S5/sloper S5/MW (better s/n on MW)
23:33 160m K1VW S4/sloper S4/MW (better s/n on MW)
23:35 160m TK5IH S6/sloper S5/MW (similar readability)
My personal feeling > in most cases the signal levels from MW were lower but quieter. The s/n ratio was definitely better on MW although the differences was not big sometime. Only in one case (TK5IH) I though that reception is better on Half Sloper because of stronger signal.
The Mini Whip stick was mounted inside of the house in the attic just 50 cm bellow the ridge of the roof. Feed-line about 10m of the 50 Ohms cable down to the radio-room. Half Sloper is mounted about 5m far from the MW using the pipes into the total height of 11m where the base coil and sloped wire is mounted. Feed-line is 27m of cable going down to radio-room. No radials yet just copper strap going along the pipes down to ground where it's connected to grounding point.
The distance between both antennas is no more then 5m.
Used radio Elecraft K3 where Notch 900 Hz masking used, AGC off, AF gain at 11 o'clock, RF gain at 12:30 o'clock, DSP BW 150 Hz (200 Hz IF Inrad).
Of course there is no doubt that this stick is not comparable to full size Beverages or full size RX loops like Delta, K9AY or even Hi-Z phased verticals array but be noted that we are looking for "makeshift" solution compare to noisy TX antennas !
Interesting results...isn't it? What do You think about it?
More information You can find here: PA0RDT or here G3GRO
73 - Petr, OK1RP
.../-.-
I do not like to evaluate or reprobate anything (specially antennas) without testing it first and mainly You never know which antenna and when will help you to hear weak signals on the TB so...I have this stick now and there is comparison with TX antenna > based coil loaded 11m high half sloper (see preview article about it)...
10/11/2010
22:45 160m W1MK S6/sloper S5/MW (better s/n on MW)
22:53 160m N3IR S3/sloper S2/MW (better s/n on MW)
23:20 160m VE1ZZ S5/sloper S4/MW (the same readability)
23:20 160m 9K2YM S6/sloper S5/MW (the same readability)
23:30 160m W8FJ S5/sloper S5/MW (better s/n on MW)
23:33 160m K1VW S4/sloper S4/MW (better s/n on MW)
23:35 160m TK5IH S6/sloper S5/MW (similar readability)
My personal feeling > in most cases the signal levels from MW were lower but quieter. The s/n ratio was definitely better on MW although the differences was not big sometime. Only in one case (TK5IH) I though that reception is better on Half Sloper because of stronger signal.
The Mini Whip stick was mounted inside of the house in the attic just 50 cm bellow the ridge of the roof. Feed-line about 10m of the 50 Ohms cable down to the radio-room. Half Sloper is mounted about 5m far from the MW using the pipes into the total height of 11m where the base coil and sloped wire is mounted. Feed-line is 27m of cable going down to radio-room. No radials yet just copper strap going along the pipes down to ground where it's connected to grounding point.
The distance between both antennas is no more then 5m.
Used radio Elecraft K3 where Notch 900 Hz masking used, AGC off, AF gain at 11 o'clock, RF gain at 12:30 o'clock, DSP BW 150 Hz (200 Hz IF Inrad).
Of course there is no doubt that this stick is not comparable to full size Beverages or full size RX loops like Delta, K9AY or even Hi-Z phased verticals array but be noted that we are looking for "makeshift" solution compare to noisy TX antennas !
Interesting results...isn't it? What do You think about it?
More information You can find here: PA0RDT or here G3GRO
73 - Petr, OK1RP
.../-.-
Sunday, January 20, 2013
ALA-1530 vs RF PRO-1 by Guy Atkins
Hello,
with permission from Guy
Atkins I am posting over here very interesting comparison study of small
receiving loops commercialy offered on the market.
Let's go to read what Guy wrote:
For the last few months I've been doing some methodical comparing of the signal-to-noise (S/N) ratio of many stations as heard through the Pixel Technologies RF PRO-1A and Wellbrook Communications ALA1530 active loop antennas. Using the spectrum analyzer qualities of the Perseus SDR receiver I've been able to be very objective on which loop antenna gives the best reception on all the LW, MW, and HF bands.
I've written a detailed review of the two loops which contains S/N charts for all bands, plus a selection of "A-B" comparison MP3 recordings and the original MS Excel spreadsheet file of raw S/N data available for download.
I've sent the review to some DX hobby web sites for possible publication, but Wellbrook has chosen to make the PDF file available now for download from their site:
I've written a detailed review of the two loops which contains S/N charts for all bands, plus a selection of "A-B" comparison MP3 recordings and the original MS Excel spreadsheet file of raw S/N data available for download.
I've sent the review to some DX hobby web sites for possible publication, but Wellbrook has chosen to make the PDF file available now for download from their site:
http://www.wellbrook.uk.com/reviews/ALA1530-vs-RFPRO-1AReview.pdf
I hope you find the comparison review useful. It was very interesting and refreshing to use a receiver like Perseus as a S/N measuring tool rather than just making observations "by ear" as I've done for all my previous reviews and articles over the years.
I hope you find the comparison review useful. It was very interesting and refreshing to use a receiver like Perseus as a S/N measuring tool rather than just making observations "by ear" as I've done for all my previous reviews and articles over the years.
Yes, you may certainly share my article on your blog. Besides the link to the PDF on Wellbrook's site, it is also found here:
and here
73,
Guy Atkins
Puyallup, WA USA
Guy Atkins
Puyallup, WA USA
I hope that You will find it interesting and motivating...
73 - Petr, OK1RP
.../-.-
.../-.-
Topband setup improvement cooking book by Greg, W7MY
Hello,
Most every one of us has gone through bad experience in the beginning so your not alone. There are a few items that are necessary to address to get the elusive 160 DX on your small lot:
1. There is no substitute for patience. I have gone years here where
I have not heard a EU station here. When the sunspots are high like now, the number of EU openings to the west coast are few and far between. That means for those without a stellar station, you may only have 3-4 opportunities per year to hear/work EU. I missed my chance about 1 1/2 weeks ago because I went to bed early. West coast EU opening opportunities peak just after your sunset and just before/during EU's sunrise. In any case, you have to be there to work them. That means you should be on alert every day watching CC user, checking the band, waiting for your
infrequent openings.
2. Transmitting. 160 is like moon bounce, EVERY DB COUNTS. Your running 800 watts so consider yourself3 db from where you should be. You described your inverted L antenna. It seems reasonable but you don't have a good ground system. Consider yourself another 2-3 DB down. There is a wealth of information about radials in the archives of this digest, read it. In any case, there is no substitute for 2000' + of wire on or under the ground. Your lucky because you can eliminate 6DB loss you currently have with a minimal effort.
3. Receiving. Your transmit antenna is the worst RX antenna you can have. Its not only bad but it can ruin other RX antennas near, and with your 1/2 acre, it will. A simple short BOG or two will make a world of difference. Remember think moon bounce, without a short BOG your probably signal to noise is 3-6 DB down than you could be. A NE BOG 200' long operating properly will get you some of that loss back and if you isolate your TX antenna while receiving, you probably will get even more. Put up a vertical RX array
or flags and you probably will even get more S/N DB's.
4. Know how to use your rig. The signals you are looking for are always dirt weak. Its taken me years to figure out how to get the best out of a RX to hear the weak ones. Spend time listening to weak CW sigs and try different filter settings, RF gain settings, CW pitch notes. I use a Timewave DSP-599ZX audio filter. It has a "spotlight mode" for CW. In this mode, on a quiet band, I can run the selectivity down to 10 HZ. It buys me another 3 DB or more S/N. My 746 PRO has a gob of settings for filters, notches, and noise reduction I use them all and in doing so probably buy myself another 2-4 DB of S/N. Many hams have not calibrated their receiver with the proper pitch setting thus they may be off 100+ HZ when looking for a weak signal. With a 10HZ audio filter, 100 HZ off FQ is infinity! Tune in WWV and calibrate everything against it so the pitch you like is right on frequency. This really helps when there is bad QSB.
You can sit on a FQ waiting to the QSB to come up without having to tune the station unless he is off FQ. Most rigs today are within 10 HZ so usually
you can set it and be right on FQ IF you have calibrated your RX properly.
In conclusion, working DX on 160 from the west coast is a pain in the butt especially on a small lot. If your crazy enough to try, you won't get there unless you fight for every DB transmitting and receiving and spend the time to be there when the band is open. Some guys get lucky and find a quiet location on rich earth, throw a wire over a tree and work DX on 160 with 100w. Don't plan on being lucky!
I'm on a 1/3
acre hillside lot over soil with the conductivity of Teflon. My antenna is similar to yours but I have lots of wire on the ground. I'm much closer to the auroral oval than you so my location is the worst of the worst for 160. I'd trade locations with you in a heartbeat. I have used short BOGS, a low dipole, loops, and other antennas for RX. I just purchased a Hi Z 3 element array I can squeeze on my lot, I have high hopes for it but know I'll have to isolate my vertical while receiving for it to work at all. If I get 3DB S/N improvement with it I'll be in heaven!
Go for it but understand that there is no easy way to get there unless luck is on your side and it looks like it isn't so go fight for the DB's.
Greg
---------------------------------------------------------
Greg Chartrand - W7MY
Richland, WA.
DN-06IFThis an excellent article is re-posted over here with permission by Greg, W7MY and it was originally pubished on the Topband reflector mailing list.
I am pretty sure that it is so nicely writen that it can by used by many of the TB beginners and maybe not only by them... Thank You Greg for this perfect job !
73 - Petr, OK1RP
.../-.-
Wednesday, January 16, 2013
Happy New Year 2013
Hello all,
before the first post in the New Year I would like to send best wishes, healthy and prosperous New Year 2013 ! I hope that New Year will bring to all of You some new good friends, keeps You healthy and will allow You to make some nice QSOs on 160m band...
73 - Petr, OK1RP
.../-.-
before the first post in the New Year I would like to send best wishes, healthy and prosperous New Year 2013 ! I hope that New Year will bring to all of You some new good friends, keeps You healthy and will allow You to make some nice QSOs on 160m band...
73 - Petr, OK1RP
.../-.-
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