Russell Bear

I currently have a Futaba 8 Channel "Super" radio. It can be set to transmit either FM(PPM) or PCM. It's now on FM with an FM reciever. I have a question about possibly switching to PCM. If I were to buy a PCM reciever, does it use a special RX crystal or just an FM one?

Thanks........

Gulliver

The same crystal is used for FM and PCM.

Hirobofly

Hi there.
The RX crystal is the same for both what you refer to as "FM" (more precisely called PPM) and PCM.

With Futaba you just need to make sure to get a DualConversion crystal for a dualconversion RX. The receiver is normally clearly marked if it is a DualConversion or not.
-Go for a DualConversion RX!

Good luck.

RJ

Russell Bear

Thanks guys, exactly what I was looking for.

davewallace

My Feedback: (29)

Hi Bear,
Remember to get the correct band of PCM receiver. Loband is 11 to 35, hiband is 36 to 60. Some newer PCM receivers have only one band from 11 to 60.

Dave

Russell Bear

OK, Thanks.....

bruce88123

PCM is also FM. It's just encoded differently. Also, your ONLY source for a RX that will match your Futaba PCM is Futaba. The coding is proprietary and nobody (that I know of) makes a compatible aftermarket RX.

It sounds like you may have a 8UAPS. I think this is a 514 PCM. I'm attempting to verifiy by my slow connection will take a while to download.

If it is a 514 you will have a hard time finding a NEW RX since they have been out of production for some time. If you need a 512 RX look for a R127DP (7 ch) or R128DP (8 ch).

You may end up better off staying with FM.[]

I'll be back with an update.

jdb000001

Make sure you get a Futaba PCM receiver - you can't mix brands with PCM, every manufacturer has a different way of encoding the PCM signal.

The 8U series of transmitters is PCM1024, so it will work with any of the current Futaba receivers. It will not work with an FP-R128DP - thats an older PCM512-only receiver. You also don't need an 8-channel receiver - I've used my 8U on a ground frequency on a 3-channel receiver and it works fine, also works with 9 channel receivers.

bruce88123

duplicate.

bruce88123

Good news, I was wrong. The 8UAPS is a 1024 system. Several RX's still in production.

Russell Bear

Thanks everyone. I'm looking for one now.

BillS

I also have the 8UAP Futaba radio and have a mix of PCM and Futaba PPM and Hitec PPM receivers.

Bill

bruce88123

Even JR makes a PPM that's compatible. It's the PCM mode that is proprietary and restricts him to Futaba if he want PCM operation.

Robotech

My Feedback: (9)

Are there any brands that are not proprietary PCM?

bruce88123

No, every mfg developed their own codes. I don't think there are any rules/laws stopping anyone from duplicating the coding. They just haven't that I am aware of. Might be a patent deal though.

BillS

My JR receivers have are opposite shift from Futaba.

Bill

bruce88123

They make some that are shift selectable. Yours may not be one of them.