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Is it possible to replace a 40Mhz crystal with a 49.860Mhz? Answered

I bought a RC submarine that was running at 40Mhz. Submarine broke, seller shipped a replacement, but replacement could not be remotely controlled by original remote. In fact, while looking under the submarine, there was a sticker written "49Mhz - 3". I guess it is referring to Channel 3 - 49.860Mhz.  So could I buy a 49.860 crystal, remove the 40Mhz crystal from remote controller, and get my submarine to run again? Is there anything else to consider???

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Thank you steveand lemonie, but I need to know for sure. I need a confirmation. Furthermore, seller is too far away, and sending back and forth replacement would end up costing more than the value of the unit, thus I must consider simply changing crystal.

The thing is RF circuit frequency behaviour is not "just" controlled by the crystal. If you'd asked for few % difference, it would definitely work, 25% is different.

One of the guys here, Slowpoke  is a true RF expert who can probably give a definitive answer- but I think he'll agree with me, I doubt it will work, but it might - there will be other parts you need to alter internal to both devices.

Steve

To help you judge: here are two pictures of the front and back of the PCB controller : https://www.facebook.com/l.php?

http://www.imageshack.us/photo/my-images/266/imag0151q.jpg/

and

http://www.imageshack.us/photo/my-images/513/image151j.jpg/

It MIGHT work, but I wouldn't guarantee it.

The seller should fix this by shipping both units as replacements, or at least send you a controller @ 49MHz.

L