Hi, I was wondering is a S-PCM(8-channel JR388s) transmitter compatible with a micro FM receiver as those used in park flyers ?

Willy,
You can use almost any transmitter with a micro receiver provided you switch your TX from PCM to PPM or FM. I have been using the little PICO RX's from Maxx Products. They have a 1000 ft range, weigh approx 5 grams without the case. They work very well. This little gem will work with Futaba, JR, Airtronics and Hitec.
Happy flying.
Pete

"You can use almost any transmitter with a micro receiver provided you switch your TX from PCM to PPM or FM. "

Thanks 4 the info

I can change my JR Tx by its software programming mode from PCM to FM,
do I also need 2 swap the hardware PCM Tx module ?

Willy,
You shouldn't have to. I fly only Futaba and all I have to do is switch from PCM to FM. After you switch it over shut your radio off and then turn it on again. This resets the computer.
Pete

GWS will rather suggest buy 2 pcs R4P, one for JR and the other for Futaba.

You will have 2 RX of GWS and pay less. Don't forget to count the HEAVY crystal of the RX. Maxx Products carry many GWS OEM logo products. But that one is not made by GWS. Do not expect the RF is as good as GWS!

It looks similar to GWS, but It is not a GWS made.