[Antennas] homebrew tuner accessory

[Durwydd MacTara]

                  Broadband "hash" generator
I want to build one that will create noise at least through 30 MHz with no 
more than a few mw of power output. I want to use as few components as 
possible because I want to mount it inside my antenna tuner cabinet, leaving 
it on all time; the idea being to adjust the tuner for a null in the 
increased noise floor on the "guess meter" of my receiver, thereby tuning my 
antenna with no qrm caused by me! I see a minor problem in coupling the 
noise to the reieever without coupling excessive RF back into the generator 
when I put my 100 watt transceiver into transmit! this possibly could be 
solved with a relay. I initally plan to power this circuit from the power to 
the meter lamps for the tuner. the other possible power source is a +12V 
receive line from my Kenwood TS-830 however I would rather not.

My first thought is a couple of ttl nand gates wired as inverters and daisy 
chained in a loop. As I recall this configuration will oscillate at about 10 
KHz with a "nasty" square wave, loaded with harmonics.

A second idea is to use a zener diode as a broadband noise generator and 
feed the noise to a couple of 2M2222 transistors for amps.

PLEASE folks, I am open to any and all ideas?
  "Communications" is a People skill, the rest is technology.
             Durwydd MacTara




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