SA602N chip

[RX5]

can this chip be used or tuned for AM??? RC use...

heres the link:

http://braincambre500.freeservers.com/Superheterodyne%20Receiver.htm

[Eric_N57105]

can this chip be used or tuned for AM??? RC use...

heres the link:

http://braincambre500.freeservers.com/Superheterodyne%20Receiver.htm


It's a balanced mixer which would be a single stage of a receiver. OK, two, if you use the integral oscillator. You would still need a few more stages for a complete receiver. In fact, the project shown is an AM receiver.

Virtually all modern RC receivers are using a single chip receiver e.g. the Toshiba TA36136, which includes this stage and nearly all of the others required for a complete receiver. It's the same chip used in cordless telephones.

Eric

[radio freak]

Hi,
I am also working on a similar project, I did ask for help on this forum but i received little response. http://hem.passagen.se/rollo/beskrivn_e.htm this site does list an am/fm receiver designed for rc use,It uses the SA605 chip.The problem is that the schematic diagram is of low resolution and I do not know how to use this receiver as AM or FM. Let me know if you have any luck with this project and if possible could help me as well.

[RX5]

It's a balanced mixer which would be a single stage of a receiver. OK, two, if you use the integral oscillator. You would still need a few more stages for a complete receiver. In fact, the project shown is an AM receiver.

Virtually all modern RC receivers are using a single chip receiver e.g. the Toshiba TA36136, which includes this stage and nearly all of the others required for a complete receiver. It's the same chip used in cordless telephones.

Eric


Hi Eric,

thanks for the reply.... We have a cordless phone but have not noticed THAT chip... I was thinking, could a standard AM radio be converted to recieve higher freq(like 27MHz)...

any info or have this been done?? just askin if at all possible...

[Eric_N57105]

Hi Eric,

thanks for the reply.... We have a cordless phone but have not noticed THAT chip... I was thinking, could a standard AM radio be converted to recieve higher freq(like 27MHz)...

any info or have this been done?? just askin if at all possible...

It could. The "standard" AM radio mixes the incoming AM signal (540-1600 khz) with the oscillator signal to produce 455Khz which then gets detected and audio amplified. You would have to change the oscillator so it tuned a range of frequencies that when mixed with 27 mhz signals produced a 455khz signal.

For example, the oscillator in the radio probably tunes 995-2055 khz. When a station at 540 khz is mixed with the 995 khz, it produces a difference of 455 khz. To tune in a station at 1600, you retune the oscillator to 2025 khz and the difference is 455 khz.

For a 27 mhz radio, you would just increase the oscillator frequency so that the difference is again always 455 khz. It wouldn't be a very good receiver, but it would work. You could do that with the little SA602 receiver in your link by replacing the "Oscillator Coil" and probably changing the 460 pf variable capacitor to something smaller.

There are lots of good sites with information about this. Search for "superhetrodyne receivers" in Google.

Eric

[RX5]

Eric,

you mentioned , it would NOT be a good reciever(with a converted AM radio).. ok... might as well search other means of radio link... this is what makes it hard... finding coils and chips ONLY to be found on the internet or through mail order...