[AMRadio] 10M AM Frequencies

[manualman at juno.com]

My 4 elements on 10 meters are adjusted for best at SWR at around 28.7
MHz. The SWR increase at 29.1 and 28.3 isn't enough to be me excited. The
tube rigs don't care and the solid-state rigs all have antenna tuners. On
10 meters, I can find phone DX all over the band. I can't stand that
dit-dit stuff so I don't operate below 28.3.

Pete, wa2cwa

On Fri, 23 Sep 2011 08:55:02 -0700 Paul Baldock <paul at paulbaldock.com>
writes:
> It certainly is an issue. A typical 4 element yagi that is tuned for 
> 
> 28.3MHz will have about 6dB less gain at 29.2MHz than at 28.3MHz. No 
> 
> antenna tuner can compensate for that. Also the front to back is 
> less 
> than zero - ie it points backwards. A 100ft of RG213 is about 1.2dB 
> 
> loss, a 3:1 SWR adds another 1.2dB, add 1dB for your tuner, and that 
> 
> adds up to about 10dB down at 29.2MHz. 100W is now worth about 10W. 
> 
> That's a big difference when you are trying to work DX and AM.
> 
> - Paul
>