#1
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Testing a Signal Generator
Any tips on verifying whether a signal generator is working? I have a Heathkit SG-8. I've replaced all the caps and swapped a 1N4004 in for the selenium. It powers up, no smoke, but I'm not sure how to verify that it's producing a signal.
Any ideas are appreciated. I'd like to get this working so I can start injecting signals on my SW-54 chassis.
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To keep your tubes running smoothly, make sure to dust underneath the glass as well. |
#2
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Dangle the output cable near a radio, turn the rf output and modulation up... set to band b on the generator.... you should be able to hear it at near the correct frequencies on the AM band. likewise, you should be ablr to hear band d signals on the FM band.
jr |
#3
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You won't be able to confirm the generator dial frequencies without a frequency counter or at least a good oscilloscope that can work at the RF frequencies.
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#4
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Some service generators are so non sinusoidal that some counters won't indicate correctly...My Heathkit and tripplet counter don't like each other so I dial in the digital tuner in my Sony ICF7600GR world band radio to the frequency I want and adjust the Heathkit for peak volume.
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Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
#5
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Is there a frequency on the B band you'd recommend I ballpark to test with an AM radio? Something that I could try and hone in on with the dial?
I'm not looking for accuracy here so much, just want to figure out if I need to do any more servicing on this.
__________________
To keep your tubes running smoothly, make sure to dust underneath the glass as well. |
Audiokarma |
#6
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Okay, I set it to band B and heard some warbling around. I was able to move the RF frequency and find it on a different part of the band. I'd say this thing is working. Thanks, all!
Now I just need to figure out how to use it for signal tracing.
__________________
To keep your tubes running smoothly, make sure to dust underneath the glass as well. |
#7
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That's a really good idea, I think I will use the same technique to verify my Stark RF generator's dial accuracy.
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#8
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Quote:
I can also use the Sony to do sneaky troubleshooting with tube radios....If I tune the Sony to the IF freq an antigue AM or FM (I didn't expect FM but found that it works) radio that is working between the antenna and converter/mixer stages (having atleast 1 good IF stage helps) the Sony will pick up any signal making it to the IF chain of the tube radio.
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Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
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