[Elecraft] [K3] KPA3 12v Sense Mod Question

[Ron D'Eau Claire]

Yes, there are several junctions in that circuit that gives you very
confused readings, especially in diode test mode. 

I also see nearly 1 k ohm from the anode of the new diode to ground. 

Ron AC7AC 

 

 

 

From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Corboy-Poteet
Sent: Tuesday, February 03, 2009 2:23 PM
To: elecraft at mailman.qth.net
Subject: [Elecraft] [K3] KPA3 12v Sense Mod Question

 

I neglected to check the circuit characteristics before installing the diode
that is added for this mod (note to self: don't do this again).

 

With the diode installed, what I see with my DMM is about 1K ohms to ground
(with the DMM set below diode barrier voltage) which, looking at the
schematic, seems OK.  If I change the DMM to check diode response, I get
about 0.5 ohms in the forward direction (again OK). But I also get about 0.5
ohms in the reverse direction which isn't right (unless the the IC on the
other end of this circuit has "opposite" polarity).   If you have done this
mod, are you seeing similar measurements?

 

 

 

Mike    W5FTD

 

 

  

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