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Portable radio is changed from FM station alone

ursebastian7

New Member
I recently acquired an analog portable radio, of those cheap Chinese. However, when I put it to work I was surprised by its performance especially in the FM band. The sensitivity and selectivity are excellent, however, this radio presents a difficulty. By keeping a station tuned and being on the move, when that station loses its signal, it automatically switches to the neighboring station, staying on it, without returning to the frequency it was in. Therefore, you have to re-tune it every time this happens. I have disarmed the radio, and I have found that it is not at all `` analog '' so to speak, since surprisingly, this radio is digital, it works with a DSP circuit, which is the KTO936MB9, which I could find little information on the internet, although I have found some images of your data sheet. My question is: Why does this radio have this problem? What is the possible solution you could offer me? Thank you!!

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Pommie

Well-Known Member
Most Helpful Member
Sounds like it's in an autoseek mode. I'd check the manaul to see if there's a manual tune mode.

Mike.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
To be fair, I've always found radios with crude mechanical tuning to be pretty useless, and they frequently drift off tune - far better to find a synthesised one that will stay where you put it :D
 

ursebastian7

New Member
To be fair, I've always found radios with crude mechanical tuning to be pretty useless, and they frequently drift off tune - far better to find a synthesised one that will stay where you put it :D
Thank you for your answers. I ask you a question, within my ignorance. I remember 20 years ago having a Walkman Casio AS200R that was totally analog and did exactly the same job as this radio. Won't some AFC be activated on the radio? If so, how could I deactivate it? Thanks again
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Thank you for your answers. I ask you a question, within my ignorance. I remember 20 years ago having a Walkman Casio AS200R that was totally analog and did exactly the same job as this radio. Won't some AFC be activated on the radio? If so, how could I deactivate it? Thanks again
There may be AFC, there may not?, not all radios have it (or had it) - and on radios that did, it wasn't usually switchable.
 

audioguru

Well-Known Member
Most Helpful Member
Cheap radios use AFC because their manufacturer claims that it follows the frequency wandering of FM radio stations. But of course the circuit of the cheap radio is what wanders and the AFC covers up its wandering.
 

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