[Drake] 2-NT VFO Choice

[Glen Zook]

Low pass filter won't work in this case.  He is talking about signals lower in frequency than the desired output frequency.


For example, a number of VFOs use the 160-meter range for 80-meters and even for 40-meters.  For a frequency of 7100 kHz the VFO operates on 1775 kHz and there can easily be signals at 1775 kHz, 3550 kHz, 5325 kHz, and the desired 7100 kHz.  


With the VFO output in the 40-meter band, when used for 20-meters, 15-meters, and 10-meters, as the band goes higher in frequency there are additional signals.  By the time one gets to the 10-meter band, say a frequency of 28.100 MHz, there are signals at the VFO fundamental of 7.025 MHz, 14.050 MHz, 21.075 MHz, and the desired 28.100 MHz.

 Glen, K9STH 
Website: http://k9sth.net

      From: Bry Carling <af4k at hotmail.com>
 To: Dennis Monticelli <dennis.monticelli at gmail.com>; "drake at mailman.qth.net" <drake at mailman.qth.net> 
 Sent: Monday, February 29, 2016 7:10 AM
 Subject: Re: [Drake] 2-NT VFO Choice
   
May I suggest using a B&W FL10-100 which is a very small Low Pass filter.

I just happen to have one for sale for $10.00(grin)