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I have a RCA 1X Schematic
http://www.nostalgiaair.org/pagesbymodel...014806.pdf
I now have it where I need to do an alignment but I have some question on the instructions.
#1 says connect the signal gen to the IF grid through a .01 cap. Are they talking about the 12sk7 pin 4?
#2 says the same as #1 but to the 1st det. are they talking about 12sa7 pin 8?
and step #4 what do they mean by Radiated signal? Draping the sig gen lead over the ant winding?
Thanks Eric
(This post was last modified: 06-20-2015, 03:13 PM by
Eric.)
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I would use the pin on (12SA7) to adjust both IF transformers. As for the RF adjustments on the top of the tuning cap One will adjust the frequency(local oscillator) and the other will peak the loop ant.
Set the dial to a local station up at the high end of the dial. Check the dial for the proper frequency. Adjust the osc trimmer to correct if necessary. Adjust the other trimmer for max volume.
Terry
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(06-20-2015, 03:08 PM)Radioroslyn Wrote: I would use the pin on (12SA7) to adjust both IF transformers. As for the RF adjustments on the top of the tuning cap One will adjust the frequency(local oscillator) and the other will peak the loop ant.
Set the dial to a local station up at the high end of the dial. Check the dial for the proper frequency. Adjust the osc trimmer to correct if necessary. Adjust the other trimmer for max volume.
Terry
Hi Terry,
Having a hard time picking the pin on the 12sa7 would it be pin 5 or 7?
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Well I'd go with pin 8. 7 is the heater,won't work at all. 5 is the control grid for the osc section of the tube. Will work but 8 is better.
Terry
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(06-20-2015, 03:38 PM)Radioroslyn Wrote: Well I'd go with pin 8. 7 is the heater,won't work at all. 5 is the control grid for the osc section of the tube. Will work but 8 is better.
Terry
I see it now in the print have it working good still not sure what they mean by radiated signal?
Thanks
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Someone correct me if im wrong but wouldnt a radiated signal be a signal from the generator using an antenna hooked to the signal generator or a lead from the sg?
(This post was last modified: 06-21-2015, 11:46 AM by
Warren.)
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Yes that would be correct. As I mentioned you can use a local station around 1400-1600kc. Pretty much does the same thing.
Terry
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