Hi all,

I assembled a cheap Chinese AM/FM radio kit 208HAF based on the CD2003 chip, a TA2003 clone. All works as might be expected for the low price but on AM the sound is a bit course, like all is overmodulated. Is there an easy way to fix this? I would settle for less volume as it is loud enough.

Another thing: when tuning to a station on the FM band there are always two stations heard at the same time. The FM receiver is also not very sensitive. That puzzles me, any ideas?

The IF filter used are 10.7 MHz. First stage audio amp is a 9014C (HFE=100), followed by two 9013H.
Additional info: http://detail.net114.com/chanpin/1005643596.html

Hope somebody can help me out. Thanks, Floyd

 

hi Floyd2
sorry that no answer yet as i want to do this circuit too ..
now try to collect every thing about it ..
wonder if you can write any important details about it with pictures maybe as the schematic is not clear ..
and what did u use for var capacitor ?

last thing . do u know any good source or Link for circuit schematics about FM /AM transmitting too ...

 

This may help you understand why you have poor reception.
http://www.geocities.ws/shreddermanrulz/myth1.htm