[Elecraft] Re: KX1 part 1 resistance checks - fail. Any suggestions?

[Martin Gillen]

Hi, Reflectees.

I did resolve my resistance problem.  Gary pointed
out that I should really be using a DIGITAL
multimeter,
so I went out and got myself one, and all the
measurements make a ton more sense.

I noted that the AC voltages were out too in the first
test & alignment point;  The analogue multimeter was
registering AC voltages of 100V+ !!  The digital meter
said 3mV ... :) ...

Here's Gary's response (in case anyone else runs into
this problem)...

Martin,

All resistance measurements in the manual were taken
with digital 
meter, not
an analog meter. An analog VOM will often give much
different 
measurements
if a semiconductor is in the circuit being tested.

D2, D3 often have a little reverse leakage, so they
may not show 
infinite
ohms in one direction.

Some ohmmeters will give different readings when
measuring active 
devices.
Some of them will forward bias a semiconductor while
others will not.  
The
main thing we are looking for with resistance checks,
is solder shorts 
or
opens. The absolute values are not terribly important
as long as they 
are in
the ballpark or do not measure much less than is
expected. An infinite 
ohms
reading is OK if >100K is specified. Reversing the
ohmmeter probes will 
also
often produce different ohmmeter readings if a
semiconductor junction 
is
involved.  

--
73, Gary AB7MY
=========
gary at elecraft.com
Elecraft Technical Support  

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