Re: A simple frequency spotting modification kit for legacy Bayou Jumpers.


 

I would like to report how I frequency spot with my original BJ. I have used the methods described in the instructions (putting the crystal across the antenna input and listening for the heterodyne with the key down in RX). Listening to the heterodyne with the key down in RX is easier than removing the antenna connection and the crystal each to time spot. The problem with my BJ is that the heterodyne whistling zones are far apart and the dead zone is wide. 
I happen to have an old Whiterook Mini-Keyer Model MK-60MB. It contains the Embedded Research chip "Tick-2". First I used it as an iambic keyer to solve the no sidetone issue and it worked well. I then decided to put it in straight key mode while using a straight key.  It also worked well. I then noticed that when I held the straight key down in the RX BJ mode I heard a very, loud heterodyne. It is not only loud but the whistling zones are close with a very small dead zone. Using a second rig and having many BJ QSOs I find that I can not only pick out my transmit frequency very accurately (both upper and lower sideband) but I can also repeat the spotting easily without removing the antenna or even adjusting my Atten or Regen. This certainly helps as my BJ has a mild drift.

I mention this not to have BJ owners buy a Tick-2 keyer (although if you have one laying around give it a try) but to perhaps figure out why it works so well and develop a simple and better frequency spotting mechanism. 

I have the original BJ and I of course did the Keyer mod with TIP42G as seen in the new BJ Rev B instruction manual appendix K

If any of the builders are interested I would be happy to make any measurements needed to find out why it works. 

72
Peter
AA2VG

On Thu, Jan 7, 2021 at 11:20 AM Doug Dukes <dougdukes@...> wrote:
I am not sure even what this is.... but if it is for the Bayou Jumper..... count me in.


--
Peter S. DeLuca
AA2VG

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