[Test-Equipment] Leader Counter

[Eric Haskell]

> 
> Hi. I recently purchased a cosmetically perfect Leader LDC-824S counter from the estate of a deceased ham. The counter (it's a 520 MHz model) has several problems.
> 
> - the right 2 LSDs (least significant Digits) are blank.
> - the 3 rd LSD is way too bright.
> - although the Left digits display the correct frequency, some segments toggle and the 3rd digit is completely illuminated.
> 
> This thing is way too pretty to throw out or part out. Any counter experts out there?
> 
> I kinda suspect the owner might have transmitted into it. I have the 80 MHz, similar model and I love it. I feel that it would be unwise to sink a bunch of $ into repairs, if the parts are even available. I just bought a 2.7 GHz 8 digit counter for < $100, shipped.....

Some LED counters use a strobe scheme were only 1 digit is one at a time.  allt the anoede  (or cathodes) are connected in parallel.  Each digit display for the same amount of time and thus appears to have the same brightness.  Sounds like your third digit is getting the strobe time for the other 2 not displayed but the data is not being updated in that time either otherwise you would see a 3 digit superimposed in the bright digit.  I would look at the signals around the driver device with an O-scope

Eric