Well - mostly de-modded! I'll expand on this shortly. R-4B s/n 10246 is sitting upside-down on my operating table, listening to and separating CW SS stations - with plenty of audio and a newly-resensitized S-meter. Oh - and that second pot is now in the junk box.
The changes needed were pretty much as Pete had found: the 150-ohm cathode resistor had to be reconnected to V1 and the wire that was going to the modded RF GAIN pot was disconnected. The extra pot was unsoldered at both the far ends and pulled out entirely. The new 10k pot for the RF GAIN control was installed (after shortening the shaft to 1" long) after the 500k one was removed There were two wires nearby that were soldered together and shrink-wrapped: these were the wires that went to the original RF GAIN control. these were re-attached. The missing 2.2M resistor was re-added to the receiver gain board. Since the receiver was already aligned with all the other circuits, I only had to re-do the "Bias and S-Meter" (6.4.9) adjustment and everything fell into place. Bob, if you need more info, Pete and I have pretty much found the same things in both of our receivers. I put a stereo headphone jack where that pot used to be, but I'm going to have to take it back out and re-do it (I haven't wired to it yet) as I've discovered that it's not a shorting jack (so it wouldn't disable the speaker if phones were plugged in - a bad thing). Of course this means removing the front panel yet again (but I'm getting good at it and can get it off and on in 15 minutes now!). The headphone jack looks okay on the front: after all, the B-Line was the only one not to have one there, so it's sort of like seeing a '34 hood ornament on a '36 Ford - most people wouldn't notice it. It definitely looks better than that extra control that was out of line with the other four in that row! This receiver is almost done, so I'll finally be able to recoup what I spent on it, plus a little more for my work. More on that, once I have the headphone situation finished to my satisfaction. I'm very happy with how this has turned out, after a lot of initial concern as to how badly this had been hacked and what it was going to take to get it back. I've had the triple advantage of having Garey's CD, a good, un-modded R-4B and Pete blazing the trail to make this happen. Of course, I did a disassembly and proper cleaning, as well as cleaning out and re-lubing the PTO separately (The PTO's come out before I wash and bake my Drakes...) So... I'm heading into the Home Stretch. This refurb was fun, as they all are! Steve Wedge, W1ES/4 To be is to do - Socrates To do is to be - Plato Do be do be do. - Sinatra All my computers have my signature with various pearls of wisdom appended thereto.
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