Graupner Mc20 Rf Module!!!

[franpr]

Hello,

I have decided to use the RF TX module of my radio for control some servos with a standar receiver.

I will generate the PPM signal for the module wth a PIC but i have one problem...

I have detected that the RF module pins are:

From left to right seeing the transmitter pins:
1- antenna
2- batt neg
3- bat pos
4- ???
5- PPM inverted signal

Do you know what is pin 4?

Well, hope you can help me...

Thanks for all!!!

Francisco

http://www.terra.es/personal/franpr

[Bruce Abbott]

Maybe nothing (or at least nothing you need...).

Or it might be an RF indicator like Futaba modules have (pin is connected to ground via an NPN transistor, when RF is detected). Try hooking a 10K resistor to +ve and see if voltage changes when the xtal is removed.

[franpr]

where do i have to conect the resitence, in the module or in the transmitter?

If i understand you, you say that it is for indicate the transmitter that the module has xtal?

Please, if you can send me a little scheme about what you think it could be, i will be so glad...

Do you think i can use the module without connecting Pin4 of it? Or i have to make with it something?

Thanks for all...

[Bruce Abbott]

Just try it without pin 4 connected. If it works, you're set!

On reviewing my notes, it appears a higher value pullup resistor might be more appropriate (eg. 1M). Here is what I imagine the circuit might look like (based on Futaba RF module):-

[MAVA]

Just my two cents...

Pin4 on my MC24, outputs 1/2 of the transmitters battery pack.

Since my radio does not not have a Buddy-Box option(it not built-in), that may have something to do with it to shut down the RF module.

I have added a futaba RF module from an AM transmitter to my MC24 and works with out doing something to pin4.

Martin