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Hi all.
I just finished recapping a model 40-150. Re-covered or replaced all the old cracked rubber wires, all caps replaced, tested all resistors and replaced all that were out to any degree. Powered on. No fire : + )
But... no reception. volume is working, but no stations coming in on AM, police, or shortwave.
Can you help me with the next step to troubleshoot this? Schematic attached.
Thanks for any help/advice you can provide.
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First thing you will want to check the oscillator. Use a second radio tuned 455 KC above the 40-150. So, tune the 40-150 to say 1000 KC, tune the other radio to 1455 KC, rock the dial on either radio, if the oscillator is working, you will hear rushing/whistling sound.
Steve
M R Radios C M Tubes
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I'm going to throw this out there because it happened to me on my 40-180 and it's an easy thing to overlook. You need to have the dial button (last button on the right) pushed in or the set won't receive by conventional tuning. At least not on the standard broadcast band.
Greg V.
West Bend, WI
Member WARCI.org
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To add to the above ideas, make sure you have some type of antenna connected.
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Did it work before you started replacing parts?
Do you have any test equipment? Signal generator, scope ?
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YES!! The push button was the issue! Also, I found that hooking up all the wires on the antenna improved reception. I thought that the three related to the phono jack would have no impact on reception, but it definitely improved when I connected them as well.
Standard broadcast reception is good. Nothing on Police Band, one station so far on shortwave, but will check that again tonight, when it tends to be better.
THANK YOU ALL for your help!
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Ready to go back into the cabinet. Thanks again.
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City: Kansas city, MO.
Looking good. I have one and it's a good sounding radio.