Batboard

Hi -

I have a D37 Spectra that I am planning on getting on 900 Mhz ham and I noticed on the A5 head that came with the radio one of the display "digits" (the "L" on Sel check on power up it looks like - 3rd digit) is out. I changed the two 10uf/50v caps on the head where there was some leakage noted and that did not make a difference in that one part of the display - otherwise the head is functional. The cap change did make the rest of the display brighter and on looking at the traces with a loupe they appeared to be intact. Is there any way to test the display somehow or is the display just shot on that one digit and there is nothing more that can be done? Any things to check would be great. I did not get to recapping the rest of the radio but I'm guessing that doing that work would not make a difference in that display issue?

Of course the "workaround" is to just make the channel names without using that 3rd digit and all would be solved..... The radio has good sensitivity, etc and power output, etc is fine.

It's either caps/corrosion from cap "goo", or the VFD driver dying. And it's always the third digit (seriously, I've seen hundreds of jacked up Spectra heads - if the display is missing segments, it's almost *always* the third character).

The circuit trace for the third digit runs directly under one of the caps, between the two pads. You will find it is open from where it goes under to where it comes out the other side. I don't have the layout here at home to give you the cap number but one of them has pads top to bottom of the board and the other goes side to side. It is the top to bottom cap. Only one trace goes between the pads. You can bet it is open. Seen and fixed many of them. Sometimes the gap is small enough to bridge solder over while others require a very fine jumper wire.

L.E.

Ok - thanks for the info on this. I'll remove the "top to bottom" 10 uF cap again and see what I missed - there are two electrolytics with one top to bottom with the pads and another side to side like you said (unfortunately I do not have a service manual for this - just looking at pics of the boards on what other sites have provided). I'll have to look closer at the traces and see.

Thanks for the help from everyone.....

I'm back at work this morning and the cap is C45.

L.E.

Ok - very good on the additional info. I removed that C45 cap and sure enough after really looking at the trace under it and really seeing if there was copper under there it was eaten away although it seemed to look ok without doing that checking - the trace was black but looked intact which was the big clue it seems. I did some thorough cleaning around the solder pads again and ended up soldering in a wire to re-create the trace/connections and all digits are working with no missing segments. Thanks for all of the help.

Glad to help.

L.E.