Hey guys,

I have Crystals of 72.630MHz (channel 42), I want Crystals of 58 Channel (72.950)- AS I have Futaba 9chp Tx with Module58, but all receivers with 42 Crystals!

If anybody want that in exchange, I 'll pay the courier charge!

Awaiting your replies...//MEROG

1. If you have many receivers on 42, easier to get one TX crystal on 42 (than changing all receivers to 58).

2. If you are looking for receiver crystals, you should make it clear whether you want single or dual conversion.

Dear Anwar, thanx for your support,

Unfortunately the thing, is I have Futaba9chp Tx with 58Module (It doesnt have crystal), So, if 58Futaba9chp module is available, its good too, but its not so easy I think to get it, so I want to change the crystals of receivers, which are easily available.

BTW, the crystals are of dual conversion, for GWS and BERG receivers! ( I have some 3-4 of them)

MEROG

Are you sure the module does not have a crystal ? Many times the module (or the small box, for lack of a better term) itself has a crystal inside, it is just covered with a black piece of tape.

It is common for people to change TX crystals in this case.

Oh, Anwar, I knew a great thing!

Then can I change the crystal with that of 42, which I have many on my Rxs?

Please clarify me, If yes, I'll close this thread and be busy in opening the module and changing the crystal!

Awaiting your reply...//MEROG

Quote from: anwar on July 06, 2009, 11:51:57 AM
Are you sure the module does not have a crystal ? Many times the module (or the small box, for lack of a better term) itself has a crystal inside, it is just covered with a black piece of tape.

It is common for people to change TX crystals in this case.

If you are asking  whether you should open the module, then the answer is I don't know, as it depends on your module type (with crystal or without crystal).  The ones with crystal are more common, in my experience.

If you post model numbers or pictures, we may be able to figure out.

Well,

the model of Tx is Futaba9chp and the Module is 58 channel TP-FSM type but without adjustable frequency knob (As this post is not allowing me to attach large pics, here is the link:

http://www.futaba-rc.com/radios/futk75.html)

Please look at the pics, mine is exactly the same. (But without adjustable knob on module).

Please suggest if I can open it or not!

Awaiting your reply...//MEROG

Merog - There are 3 types of modules.

1) Synthesized (which is the one you referred to above). You can just change the two dials, and set it to any frequency.

2) Non-synthesized No-Crystal type - You have no option but to change the module, to change frequencies (unless you want to open it up fully and tune using the electronics, which must be possible if you have the right tools for frequency checking etc, don't know of anyone doing that).

3) Non-synthesized With-Crystal type - You can change crystal, and move to another frequency.

So unless you clarify your situation between [2] and [3], we cannot proceed.  Just check if there is a black tape on one side of the black module box.  At your own risk, you may try to open just the tape, and see if you can notice a crystal inside.

Or you may just forget the whole thing, and just look for receiver crystals of a module in the right channel.

It is "recommended" that even for the module of type [3] above be re-tuned after a crystal change, but it is normally well within allowed tolerances if you are in the same band (in your case, you are in high band which is channels 31 through 60 before and after the crystal change, so you should be OK).

NB: If you count the 2.4 modules also, there are more choices in addition to the 3 listed above.

And here is Futaba's official response on this.

http://www.futaba-rc.com/faq/service-faq.html#q2

Thank you very much Anwar,

So, I think my search continues for the 42channel crystal!

Thank you very much once again!
MEROG

No big deal Merog...  I think in your case, it is best not to try something you are apprehensive about.

I have changed the crystal of my 9CHP once, and a while later moved to a synthesized module.  It is no big deal if you are confident about it.  Otherwise, leave it alone.

hey merog i picked up a Futaba 72mhz - 42 channel module n antenna for 20$ shipped to india form rcuniverse.com

there are some synth. module sale going on see them

sahil

Thanks for bringing up the buy and sell section of RC universe, as most people do not seem to be aware of this option, although I did mention it earlier :  http://www.rcindia.org/chatter-zone/what-rc-activity-did-you-do-this-week/msg825/#msg825

There are some great deals there.  You will need to do Paypal, and many sellers refuse to ship outside the US/Canada.  Still there are many bargains to be found. 

For example, I just noticed our own Adarsh bhai looking at a Futaba 9CHPS, which is listed at $150    :  http://www.rcuniverse.com/market/item.cfm?itemId=529980

yeah i have seen Mr.adarsh at rcgroups looking for 9c 

Hey guys, I have experimented with all the stuff Last night!

It was successful, and I could fly now!

Thank you all for ya great concern!

MEROG