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Yesterday I finished putting up a horizontal dipole antenna designed to maximize use on the 80 meter band (65 feet for each leg, elevated to 20 feet). I am quite proud of it and it seems to be performing rather well on a cheap Chinese SW radio purchased from Amazon a few years ago for less than $15. Connecting it to my 2B has produced results that are dismal when compared to the cheap Chinese pocket radio. I know that there are 60 years of technology difference between the two radios and I am really not comparing one to the other. But I was expecting better results than one barely audible CW transmission. As has been suggested, I am going to test the tubes in my 2B. I have a complete set of replacement tubes to test with (and what the seller claims to be NOS, but many of these are as questionable-looking as the old tubes that came with the radio when I purchased it). So, how do I test the tubes? Replace each in the radio, one at a time, and judge the result? This must seem painfully obvious to all of you, but I have no real understanding of vacuum tubes (other than the vague concept that they were eventually replaced by transistors). But do not give up on me yet - my inabilities and lack of knowledge on this subject gets worse. So, in this process of replacing each tube, I assume that I must turn the radio off before replacing a tube and then turn it back on to judge the result. But what result am I testing for? A difference in what I hear coming from the speaker? Or am I testing for some other outcome? If listening for a change in the sound coming from the speaker, this seems to be a bit subjective as a test, but I will manage it if that is the system. If then, what shall I tune the radio to - a working CW transmission? The calibration tone generator? Dead air space? And because I believe that different tubes relate to different circuits, I wonder how useful this approach is if I am not maximizing the particular circuit that the tube has an effect on so that I have some better chance of detecting a change in the sound coming from my speaker. The scenarios on doing this right seem to be something short of endless - but maybe I am just over-complicating it. So, looking for forward to useful suggestions here on how to really go about testing each tube. And thank you for indulging me... Richard W2ONE

There was a thread a couple of months back about removing the AC mains out of the TR7; it was suggested to use a male cinch-jones plug to jumper the AC switch send back to the PS-7 supply. Finally got this done tonight (cinch-jones sourced at Surplus Sales of Nebraska) and I'm switching the PS-7 on remotely with one of those wifi-connected remote sockets that I have all over the house. Works great. Was somewhat surprised that the radio still uses the on-off switch on the volume control to switch DC inside the radio. Now...I have no FA-7 fan as there's nothing to drive it. I bought a small 12V temp-controlled PWM fan driver from AMZN and will use that to drive an 80mm Noctua PWM fan; I've used these before on several CPU builds and they are high quality and silent. I haven't yet figured out where I will mount the fan control board but probably will follow the lead of Scott N7NB and mount it where the fan's AC outlet once was. As a bonus, last weekend I went through ALL of the pieces and parts that I've been hauling around for years through several moves. I found a "Chinese Toolbox" offering at Harbor Fright (you buy a toolbox and there is a smaller toolbox inside and yet another smaller toolbox inside of that one and so on) and now I have one entire large toolbox dedicated to the TR7. In the parts cache, I found a Network Sciences 5645Khz IF filter with 300Hz width. I verified that this fits in the TR7, and added it to the "resistor" slot on the selectivity board. Now I have 2.3/1.8/.5/.3 IF filters. Can't listen to AM anymore but I have other radios for that. Will update once I get the fan installed and working in "temp sense" mode. -- Craig/W8CS Greenville, SC

The TR-4 manual states the receive sensitivity should be "less than 1/2 microvolt for 10 db S+N/N." The manual also states that each S unit on the S-Meter corresponds to approximately 5 DB. If I establish a reference point on the S-Meter for just noise, then feeding a 0.5 uV voltage into the antenna jack should, at a minimum, increase the S-Meter by two units. Is that an oversimplification? If so, what is a better way to measure S+N/N. I seem to recall that when I was doing that for the Collins R390As I had, I was using an audio level meter (TS-585) and using AM detection to measure the increase so maybe that's a better way (although, sadly, I no longer have that TS-585). Thanks, Barry - N4BUQ

You just saw it in a previous post. This one came in with a mid-late C Line, with a cut cord. Since I had to replace the cord and test it, I tried my “new” (to me) use of a gland strain relief. All voltages good, tested with a TR-4 after verifying voltages. Supply hums a little (the supply itself — not the audio). This is an original supply that has not been rebuilt. I can rebuild for an extra $150, including parts. $120 plus shipping from central NC (27253). Also have an MS-4 that is decent for $50 plus shipping. Shipped separately from AC-4, of course. The rest of the C Line will be available but not for awhile. The transmitter needs to be revived and receiver is pretty grotty. Receiver is mid-Late with a full deck of CW filters, Sherwood mixer and power supply upgrades. 73, Steve Wedge, W1ES Time flies like an arrow. Fruit flies like a banana. Sent from Proton Mail for iOS

Okay, this one is strange. I may have bodged something and may need “second sight”. I had to replace V1 socket because I ruined one pin whilst removing resistors. Rebuilt using a socket from a parts rig and reconnected everything, as far as I know. Xtal oscillator adjustment went fine. Peaked 40, 15 and 10. Receive is great on all bands. 10 doesn’t elicit S meter response but receive is strong. For an early set, receive is fine. Transmit is the opposite of what most people see: 15 and 10 are pretty good. 20 and lower are almost nothing. It was providing plenty of power before the repair. Now — it’s QRP. Counter sees correct frequency but power out is nearly nil. Reading the rotary switch diagrams is torture. Anything jump out at any of you? Steve Wedge, W1ES Time flies like an arrow. Fruit flies like a banana. Sent from Proton Mail for iOS

I'm working on a TR-3 with the dreaded "bouncy meter". I have one plate amperes meter. These can't be swapped because they're mirror image of each other but noticed that the deflection is different in each. Does anyone know what these meters are calibrated to (i.e., what is FS current for each)? Also, if anyone has a spare S meter, please let me know if you're interested in selling it. 73, Steve Wedge, W1ES Time flies like an arrow. Fruit flies like a banana. Sent with Proton Mail secure email.

I was trying to re-seat the LSB bulb to the chassis because the bulb was intermittent. In doing so I think the positive side of the bulb housing touched ground some how because when I turned the TR-4CW back on and the amp meter light, frequency light, LSB, and USB lights were not lit. Then the filament fuse blew! I replaced the wire with #26 AWG and pulled both LSB and USB out and re-seated them and made sure nothing was shorting to ground. I quickly turned on the rig but still those lights would not light. The only light that I get is the round red light on the right side of the frequency read out. I connected my power supply to my other TR-4CW and that rig works OK so the power supply is still good. Not sure what is going on? Mark

I have a 1A, Serial #331, an early one, and another later one with WWV. I didn't realize that the original version did not have a crystal calibrator (I knew it didnt have WWV) until I opened them both up for recapping. The "newer" one also has a couple of sub boards, the original does not, though the components seem to be there. I don't have and cannot find the manual or a schematic for the older unit, just for the newer one from BAMA. My question is does anyone know what the WWV mod, (which could be performed by Drake) consisted of? I assume it was not a difficult mod, and that the bandswitch has another contact for WWV. I have replaced the tuning dial with another I had, which has the WWV marking. Was thinking of adding the calibrator and WWV mod, but since no schematic of original old version its not obvious what was added. I have a third unit Which works but missing knobs and face place, its a shame to use it as spare parts. Thanks, Ed W1FU

i have seen pictures of a matching speaker for the 1A in advertising, but have never actually heard of one. Did they actually produce it? It looked like it used (or would use) the same 1A cabinet. Was thinking of making one as I have another cabinet, but did they actually exist? I use a 2A speaker, which looks good. Thanks, Ed W1FU

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For sale: Drake L4B and power supply. Very good condition. Eimac 3-500 tubes. 1200 watts output with 100 watts drive. $1,000 shipping extra. W3RJ -- This email has been checked for viruses by Avast antivirus software. www.avast.com

Gentleman: For a TR-4C, is there any difference between 6JB6A brands? I'm buying 3 of them and there's some well known brands available such as Sylvania, GE and RCA. RCA a bit cheaper. All NIB/NOS. Any recommendations? 73 Marcus PY2PLL + PY3CRX GG66rf

When tuning up my second TR-4CW the current meter goes to 0 when I push in the load control to tune it. I can see the load control working on my external power meter just nicely. I figured it was the switch. I measured all 3 terminals on this switch compared to my other TR-4CW (that doesn't have this issue) and my ohm measurements are pretty close so I believe the switch is OK. Not sure what to do next? Mark

There is an IO group devoted to Leo Myerson's equipment. Leo made a huge impact on amateur radio. If you have an interest, please join us at: /g/WRL-Galaxy-Radios Tnx, Dale W4OP