Re: Another mod to the Bayou Jumper


Jim Sheldon
 

Hey Jim, I think it will fit.  I just checked the data sheet and from the mounting surface to the top of the dome is 24.5 mm.  That's about a half mm under an inch.  I just stacked a couple of bug weights on top of each other and the height came out to just about a mm over an inch.  The lid of my box will close completely without hitting the top weight on the stack.  I measured it real carefuly with a 6" steel rule that has both mm and inch scales on it. 
 
There should be plenty of room on the underside to do whatever is necessary to make it fit once you remove the original tuning pot and you won't have to cut any traces to do the tuning direction mod.  I didn't anyway, I just didn't solder the two outer terminals on the pot.  I bent them out and soldered cross-over wires from them to the appropriate holes on the board.  Much easier than cutting traces and easily restored to original condition if necessary.
 
I may have to see if I can buy another front panel as I have 3 mounting holes drilled for the vernier in mine now and a new panel would certainly make it look better.
 
I just ordered a couple of those pots from MPJA.  I am a regular customer of theirs. I buy all my normal QRP travel cases from them (the yellow Pelican knock-offs that are about 1/2 or less than Pelican wants for them and they really work nice.
 
Jim - W0EB
 

Check out this part from Marlin P Jones

http://www.mpja.com/10K-Ohm-10-Turn-Variable-Resistor-with-Dial/productinfo/32676+VR/

http://www.mpja.com/download/32676VRMech.pdf

It's a ten-turn 10K pot with a "clock face" dial. $6.95
To use it as a replacement for R8, just change R5 to either 6.2K or 6.8K
The fact that it's a wirewound pot is not an issue, as there is only DC on R8.

The problem is that it projects a bit over 1" above its mounting surface, so some pretty good surgery would be needed to the panel to allow the box lid to close and latch. It would have to be recessed into the panel by 3/8" or so.

N5IB

Join main@4SQRP.groups.io to automatically receive all group messages.