Re: {Collins} 866A semiconductor replacement

Hi Tom
The subs are a great way to go IMHO except I miss the purple glow!
Depending on your VOM you can get a variety of readings, mostly meaningless if the device is good e.g. one ones I have tested and known to be good in service checked on my Fluke dvm and Weston analog vom both indicate a resistance one direction of about 40megohm The dvm indicates same in other direction, the analog indicates an open circuit Neither will measure a forward conduction because the ohmmeter voltage is not sufficient to cause conduction and aided by fact that the good subs contain an internal ballast resistor I think if you start series connecting a quantity of diodes you would find the same thing happening
Just for knowledge, I strung a few 1 amp diodes in series to try
The analog meter quit after two diodes, the dvm after five
Take two different model meters and probably will get different results
Oh, and I should add the dvm was being used in the diode measure function after the original resistance check yieded nothing of interest.
Happy Field Day
Paul K0UYA
----- Original Message ----- From: "TH Consulting" <thankins@xxxxxxxxx>
To: <collins@xxxxxxxxxxxxx>
Sent: Saturday, June 27, 2009 1:59 PM
Subject: {Collins} 866A semiconductor replacement

Hi to the list--anyone out there have any experience with plugin direct
replacement 1N2637 diodes for the MV 866A. I have 6 of them and show no
continuity using a VOM(forward or reverse). Am I overlooking something?

Tom Hankins


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