Hi all,
maybe you remember that long time ago I tried to create and keep updated the list with "unfavorable frequencies > the frequencies which are QRMed in some locations or somehow horrible to use...Unfortunately, this little idea has sunk in overtime…
So now I am coming back with that idea updated 3-May-2024, and I will try to keep it up!
As many of US hams reported in the past, topbanders should avoid frequencies 1810, 1820 and 1830 because on the west coast US commercial radio stations create on these frequencies of the harmonic frequency, they cause on 160m interference up to S9 and prevent them from receiving.
The "Unfavorable DX frequencies" table on 160m (original article 4-Mar-2007)
Hi all,
from my experiences with DXing on Topband I found that there are some frequencies which are not usable in some DX locations cause of local heavy QRM over there or permanent local BC interfered signals or other problems.
These frequencies are permanently unusable or even unfavorable for DXing in that DX location and its not efficient to calling CQ or looking for DX from that location overe there...
In my oppinion it will be very usefull for all Topband enthusiasts to have the table of that "unfavorable QRGs" available for quick check if needed. This table will be updated as many time as possible.
| QRG (kHz) | Unfavorable range (kHz) | DX-location | Comments |
| 1820 | 1819 - 1823 | JA | permanent BC QRM in JA around 1820 |
| 1818 | 1815 - 1821 | ZL | strong QRM from local GPS correction on 1818 |
1810 1810, 1820, 1830 USA west coast BC harmonics interference up to S9
Information about another "unfavorable QRGs" in Your locations are welcomed for sure! Please let me know by email or in comments bellow...
73, Petr OK1RP
