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Old 02-28-2015, 10:50 PM
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wa2ise wa2ise is offline
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Quote:
Originally Posted by dieseljeep View Post
There's nothing in the rules, that say the IF frequency, has to be 455KC. I'm actually surprised that the IF is 262KC. I guess they used it to minimize images, the same way, they used 262KC in most car radios.
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TV sets back in the early post war days used an IF around 22MHz, then later 45MHz. But that was after channel 1 was deleted (channel 1 would have been in the middle of the 45MHz IF bandwidth).

Some prewar 45MHz band FM radios used an IF around 8MHz.

I think the FCC avoids assigning powerful transmitters on the popular IF frequencies. 455KHz, 10.7MHz, 45MHz and so on.
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