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City: Alexandria Virginia
I picked up a nice 42-365 with the cabinet in excellent shape. I replaced all Caps and have been through almost all resistors, replacing all out of tolerance ones. I stopped to see how I was doing, and I only get static when powering up. This set has pushbuttons. I cleaned all of them with with deoxit. I don't believe there is a button for manual, just stations and television. I know that manual must be selected for sets that have it, but I don't think that is the issue here. Is there something I am missing about this one?
Thanks for any help!
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City: Jackson, NJ
Have you tried the generator signal to pass through? That'll tell you right away.
Also, have the tubes been verified to be good?
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 65
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Joined: Oct 2016
City: Alexandria Virginia
Thank you for responding. Unfortunately I do not have a tube tester. All I can say is that they are all lit. I hope it doesn't come down to me buying new tubes with the hopes of replacing a bad one.
I didn't understand what your first question means.
Thank you again.
Posts: 15,825
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Joined: Oct 2011
City: Jackson, NJ
My first question meant: you take an RF generator and put a signal through your radio in order to trace where it stops.
Let me guess, you are hoping to restore radios with no tools, the sole infication of the tubes' functonality being they have good filaments?
That is not very likely going to work.
Do you have any friends nearly/any local radio club who could test them for you?
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Joined: Oct 2016
City: Alexandria Virginia
Ok thanks for the sarcasm.
Posts: 15,825
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Joined: Oct 2011
City: Jackson, NJ
I can be a bit sarcastic...sometimes. But I am trying to help. It is possible that we here can by asking multitude of questions and gaving luck on our side figure out what ails your radio. But if you are hetting into this hobby - some equipment is necessary to have. You could of course keep spending money on full sets of known good tubes every time you start a project, and an RF generator is 20-40 bucks.
Tube tester is more. But it is a one-time investment. This is all I ever use.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 7,286
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Joined: Dec 2009
City: Roslyn Pa
To answer your question about the pushbuttons it looks like on the schematic that the band switch switches between manual and pb. The pb only select the station and the set off/on. It looks like it goes manual- pb- then the SW bands. Haven't had any hands on if this model.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 65
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Joined: Oct 2016
City: Alexandria Virginia
Yes it seems pretty clear, but I wanted to make sure there wasn't something I wasn't thinking of. I am new to this. I fixed up a 39-7 which has a manual button, and extensive cleaning was needed to get it to get any reception.
Thank you
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City: Linn Creek, MO
There is a couple of things you can do that don't require any test equipment. First, touch the center terminal of the volume control. You should hear a 60 cycle hum. If you hear the hum, you have proven that the output section and the power supply are working. Next, place a working radio next to your 42-365. with both radios turned on, tune the 42-365 to about 1000, tune the working radio to about 1455. Now, rock the dial on ether radio. You should hear a rushing sound or possibly a whistle coming from the working radio as it picks up the local oscillator of the 42-365. If you haven't already, double check all your work. Check the part values against the schematic and make sure each part that has been replaced is connected to the proper terminals. Make sure your solder connections are good. Take voltage measurements on all tubes and compare them to the service information.
Steve
M R Radios C M Tubes
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Joined: Oct 2016
City: Alexandria Virginia
Steve thank you very much. I appreciate this advice and will try these things. I'll let you know how I make out. I checked my work, but i'll check again because I easily could have missed something. For this radio I did a lot of work before checking it out, whereas on previous sets I've done an initial power up after replacing the filter caps to make sure I had life. I guess I got over confident. Also, I do understand it certainly could be a tube, and I know I need to get a tube tester, but I've been putting that purchase off. I'm new to this, but in the dozen sets I've worked on so far only one has actually needed any new tube. I also don't know which tester to buy.
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Joined: Oct 2016
City: Alexandria Virginia
Steve, pardon my ignorance, but I'm not quite sure what you mean by "touch the center terminal". I actually put my finger on it, and the static was slightly muffled. I'm not sure if though if I picked up a 60 cycle hum. It certainly wasn't obvious. Next I brought a nice working radio at 1455 very close to this one tuned the 42-365 to 1000 and didn't hear the oscillator. I guess this failed these tests.
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City: Alexandria Virginia
Wait hang on. I absolutely heard a 60 Hz hum when touching the middle terminal upon trying again!
Posts: 65
Threads: 4
Joined: Oct 2016
City: Alexandria Virginia
Ok I believe I have proven the output section and power supply. I heard nothing from the local oscillator when brining the other radio with both tuned as you described. Hmmm does that mean the LO is bad?
Posts: 7,286
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Joined: Dec 2009
City: Roslyn Pa
No just means that it's not working for some reason. There could be an issue w/the pb, osc tube, or bandswitch ect...
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 65
Threads: 4
Joined: Oct 2016
City: Alexandria Virginia
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