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Old 8th Dec 2017, 3:51 pm   #36
Neil Purling
Nonode
 
Join Date: Jul 2005
Location: Hull, East Yorkshire, UK.
Posts: 2,083
Default Re: Two or three IF stage Chinese radio kits.

I think that we can agree that the one IF stage/six transistor radio is a very crude creature. But what do we expect for six pounds or less, shipped to your door?

I think that the fact that people have found the White & black IFT's are not often set near to the proper frequency would immediately discourage the inexperience constructor.
You switch on & you don't get radio, it seems silent. If the cores were 'way out'. Can you do anything 'by ear'?

I saw Shango066 doing one on the 'Tube. He has a tasty HP signal generator, it has a built-in digital frequency readout. The point is the IF seems to posses two peaks, or else the stage can still tune out to over 500Khz. He had it all reasonably aligned by ear only to discover the IF was over 500Khz.
So he had to use the generator and do the tracking all over again.
Where the gentleman is (Los Angeles) there are stations all over the band, wheras for my area the only station at the low frequency end is R. Caroline. Alignment by ear is not an option for best results.

I don't even think that the Chinese printed 'instructions' has the actual IF frequency printed on it. I think that Shango066 was guessing it was about 460Khz. IF in a AM radio is usually 455-470 Khz.
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