On 02/28/2011 09:49 AM, Paul Christensen wrote:
>> 6. *On the top of K5, no two pins are connected.* AHA! It seems to
>> me that the pins on top are the contact pins, and that two of
>> these should be connected at all times.
> I think your reasoning is good. I'm not sure how the amp ever worked
> with the configuration you've described. K5 has all terminals
> populated. Two on the bottom for the coil and three on the top for
> the SPDT operation. Coil resistance is about 300 ohms.
> There should be DC continuity between RF IN and RF OUT when the amp is
> powered off and the RF AUX ANT switch is in the THRU position. When
> the slide switch is placed in the AUX position, you should measure DC
> continuity between RX AUX ANT and RF OUT.
> I'm not sure the vacuum relay is actually bad -- or that it's simply
> not wired correctly. Check for continuity on the relay terminals and
> if possible, apply 26V from an external bench supply to activate the
> relay for DC resistance measurements. If it's still bad, I would go
> for a new 26.5V Gigavac GH-1 from MaxGain.
>> "The tuned/untuned switch does not appear to work.
> I think it's correct based on your description. If you look at the
> schematic, the tuned network is a switched shunt leg to ground. The
> tuned/untuned INPUT switch only has two terminals connected.
> Paul, W9AC
Perhaps I was not clear in my description. I did not actually figure
out what went where. There were three connections to the relay, and a
continuity test showed that nothing was connected to anything. Since
this looks like a SPDT relay, it looks like the center paddle is burned
off, or something like that. I think that I may have a 12 volt or
higher wall wart that I will use to excite the relay, with the
continuity tester attached.
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