Quote:
Originally Posted by dieseljeep
......The set does have a form of RF stage, using a 7C7 sharp cutoff RF amp and only a two gang tuner.......
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Thank You dieseljeep , I was sure my eyes weren't deceiving me and that the 7C7 is most certainly an RF amp . To me , to be honest , I'd rather the sixth tube , if we're going from an AA5 to a six tube radio , be an additional IF amp stage rather than an RF amp . The additional IF stage would benefit selectivity but costs the extra IF transformer as well . The RF stage is not as much about improving the radio's DXing abilities as it is about keeping the set's local oscillator from bleeding back through the antenna and becoming a little mini transmitter itself , emitting a signal that interferes with neighboring receivers . The separate RF amp isn't set to amplify much stronger than the the pentagrid converter (single tube in an AA5) would be , and with no separate transformer or extra gang on the tuner the addition of the single RF tube is a cheap way to keep the local osc signal where it belongs . The extra tube was a great selling point too , back when numbers of tubes was supposed to be an indicator of radio superiority .