Bayou Jumper - signal overload when spotting crystals


Jim, N5IB
 

Recall that a regen detector can be pulled or blocked by a strong signal. That crystal oscillator inside the same box as the Rx is a really strong signal!  The poor detector is in apoplexy...

While my rig is not an official Bayou Jumper (it's the 1st prototype) the Rx part is nearly identical. To spot my crystal I turn the attenuation to max, the regeneration to max, and the AF gain barely above zero. I can generally get a true zero beat without a dead zone. Turning the regen all the way up makes the detector a more independent oscillator and less susceptible to pulling - a fact worth remembering if you're working a strong station, or trying to listen to a strong SSB station.

Ultimately I build a small spotting oscillator that turns on when you press a crystal against the two contact pads (no socket) a microswitch on the bottom does the trick. The circuit is just a copy of the oscillator section of a Tuna Tin 2. I'll put a picture in the Photos area.

Jim, N5IB



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