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My 410B has a built in 22 megohm isolation resistor built into the DC probe. My GR VTVM does not but I put a one meg resistor in series with it. It has a 10 meg input resistance so the extra megohm

Richard do your DVM’s have an isolation probe for capacitance decoupling back to the DOT? Resistance of DVMs can be very high, but test wires have capacitance that will mess with tuned circuits as

Thank you, Don. No, the set was not operating when I acquired it last year. It is dead on all bands. Over the winter I through it and replaced all resistors and capacitors, upgraded the power cord to

Thank you, Jacques. The problem is on all bands. I have replaced all the resistors and capacitors in this set except for a large mica cap buried under the oscillator coil assembly. I was hoping not to

A DMM and a VTVM are essentially the same. I prefer the term "electronic voltmeter". The voltages for the S-20R were probably taken with a passive VOM. I don't remember if the meter characteristics

Hello Tom Around the HF, especially the LO, I wonder if you can trust a DMM having only wires {no isolation probe } at some pins. It never did work while you have had it? Assume, you tried another

Hi Tom, The triode section of the 6K8 is effectively not oscillating, and that explain all the voltage readings you got. There should be an open coil somewhere, or an open capacitor in the oscillator

Newish member of this group, first time posting. I have an S-20R in need of repair. I am not a trained technician and am not particularly good at interpreting symptoms. However, I do have the chassis

Ok Dwight, I’m planning a trip to the observatory in the next few weeks pending weather. I’ll need to get contact and address from you. Do you want a deposit to hold the receiver (and possibly

No, you are the first one to claim it. So I will wait until you are in the area to hand it over to you.? The other Collins radios in the photo are also up for sale.

BTW, have you sold your R-274? Tom ?N5AMA

Well, you and I seem to differ on the value of that thread. I learned several things from folks here who have a wealth of knowledge. 73, Maynard W6PAP

So new thread started on the same dead horse. how many weeks will this one run? 52 HOPE IT BEGINS TO WORK

So new thread started on the same dead horse. how many weeks will this one run?

Hi Jim , and all; revising numbering makes it tough to compare things !!!! So the Halli C62 function remains despite our communication inability. I guess that it one reason I often take a snip of what

Maynard FYI S-40 [no suffix] https://bama.edebris.com/download/hallicra/s40techman/s40techman.djvu This seems to have no C62 and looks like “your” 40A at first glance ..SO maybe you have an early

The S-40B Photofact Folder that I copied calls it C7 but it is still a 2.2 pF cap just as is C62.? Sam's has a format that they follow so their component designations are not the same as

Maynard, yes wording is tough. “C62” had been started.. then it moved To me it showed that it was thought to be needed for a simple coil, but not for a transformer .. A version Then when the B

And my S-40A schematic is from Sam's Photofacts (via the Web) and it doesn't have C62 as in your schematic nor does it use independent designation of each component, but labels them with numbers

Hi, Don, When I said that there is no C62 equivalent in the S-40A, I meant that there is no capacitor like C62 that is connected around the switching and resonant circuits so that it is completely