Ferocious Frankie

My Feedback: (7)

Hi Guys,

Long time not talk.

Will this combination work? A Futaba PPM/PCM transmitter with JR electronics.


Thanks

MikeL

My Feedback: (3)

Nope. They're incompatible. Futaba is negative shift, JR positive shift. What that means is that they place the data on opposite halves of the transmission's sine wave.

ho2zoo

My Feedback: (5)

The servos will work, as long as they're plugged in the right way. Just not the receiver.

bigedmustafa

My Feedback: (2)

JR actually offers flight packs with a shift-selectable receiver that is completely compatible with all Futaba FM transmitters:

http://www.horizonhobby.com/Products...rodID=JSP40020

This receiver is available seperately, as well. Hitec also makes a number of shift-selectable recievers that they include with flight packs or sell seperately. These kinds of receivers can be used with transmitters of either shift type.

The higher-end Airtronics transmitters (RD6000 Super/RD8000) are shift selectable, and will work with Futaba receivers.

You can use JR flight packs with your Futaba transmitter if you pick the right receiver, and you can use Futaba flight packs with your Airtronics RD-series transmitter.

bruce88123

You will need to operate the TX in PPM mode.

simhatus

Hi

I have a few jr ppm recievers they seem to work fine with my futaba tx. Just need to make sure the rx crystal is a jr crystal and the tx has a futaba crystal. pcm ones wouldn't work.

Simon

bruce88123

This should not work. What model receivers do you have?

Ferocious Frankie

My Feedback: (7)

Thanks guys. That's all I wanted to know.


Thanks Again!

simhatus

Hi bruce

Not sure without looking will find out.

Simon

piroflip2

Futaba TX with JR RX no problem, I have several combos like this since buying F9 trannie. Those who say it wont work are wrong.

bruce88123

JR and Futaba say they won't work.

Mac_Man_UK

In the USA this WILL NOT WORK, However, some of the questions are being asked from the UK.... here they WILL WORK !

It is only in the USA do Futaba use the opposite shift to JR (and to Futaba for the rest of the world! )

marcellus

JR PPM Rx Futaba PPM Tx work just fine in Europe and other places except the USA, where this shift is different between the two. One negative one positive, as MikeL says - and also Mac Man as I typed my response!

gwh

There are a couple of issues going on here.

Since the original question is from someone in the US I'll assume we are talking about 72 Mhz radios.

In general a 72 Mhz JR RX will not work with a 72 Mhz Futaba Tx because of the shift issue. There are a few JR Sport receivers that are shift selectable that will work with a Futaba Tx.

On other bands there is not a shift issue and it is possible to use a JR FM Rx with a Futaba Tx. This is why the person from the UK has no problem.

bruce88123

Ahhhhh! No Shift? Makes sense now.

jkhorvath

My Feedback: (1)

I have read that the update to the T14MZAP transmitter provides for the capability for this Futaba radio to transmit the JR PPM signal (only FM, not the JR S-PCM signal). Therefore, this combination of Futaba transmitter and JR receiver should work for PPM/FM, however, I have never tried it myself. I only have Futaba receivers.

bruce88123

I don't think we were talking about a $2200 TX but you are correct.

MikeL

My Feedback: (3)

There are plenty of exceptions to the rule here in the US (which is the market we're talking about, as the OP is from California). I don't think it serves the purpose of the Beginner's forum well, however, to point some of them out. If a person has a question about a specific piece of gear, that's naturally a different situation. Futaba (followed by Hitec) has foisted this particular problem on us.

Just keep in mind that in general, in the US, JR receivers won't work with Futaba transmitters. Until you've got the various compatibility quirks down, ask questions and double check product descriptions.

bruce88123

Awful one-sided of you. I prefer to think JR foisted this on us. JR also has reverse charger plug polarity so add that to the mess.

Honestly, it doesn't matter. It just is what it is. Deal with it.

MikeL

My Feedback: (3)

If we were talking about charging, I might have mentioned that. We're not talking about charging. Why confuse the issue?

BarracudaHockey

My Feedback: (11)

North American markets get negative shift Futaba transmitters, the rest of the world gets positive. Why? Who knows, but thats the way it is and Mike is right, unless you are talking a few very specific products its best not to confuse the issue.

Montague

Just to nitpick a little...

The "shift" referes to the direction the signal is modulated. I'm not sure if that's what was meant in the quote above or not, but I thought it unclear.

This website has the absolute best description of what is going on that I've seen anywhere. It's worth a read:

http://www.torreypinesgulls.org/radios.htm

The short form is that our FM Tx's only actually use 2 frequencies, the center frequency (72.030 for channel 12, for example), and a frequency 5khz off. Some brands use the "higher" side and some the "lower", so a JR positive TX on channel 12 uses 72.030mhz and 72.035mhz, while a negative shift TX will use 72.030mhz and 72.025mhz.

So, if an RX is expecting a signal +5khz away from center, but it's actually -5khz away from center, it won't see it, and vice-versa.

carrellh

There is one specific "JR Sport" RS600, six channel receiver that is shift selectable to wok with Futaba transmitters in the US market.

This is copied directly from the Horizon web site.

http://www.horizonhobby.com/Products...rodID=JSP30600

Based on the popular R700 that topped the performance levels of all other FM receivers tested by a well-known independent lab, JR SPORT’s new 6-channel RS600 is a proven, shift-selectable receiver engineered to operate with all major transmitter brands, including Futaba and HiTec.

electricpete

Just to add to the confusion. I went to the modelshop to buy a battery for my glider (to go flying) and asked advice on my sythesised JR RX with my 9C futaba TX as I could not get it to work on channel 90. The model shop thought it would not work on any channel. It would not work on 90, but would work actually on 62 and 63. Although I bought the RX to use at sites I don't usually visit and just a few TX Xtals should give me a flight. I stayed on 62 and flew on it quite sucessfully, as far as radio was concerned.

Does anyone know what frequncies I can use it on? as I cannot afford a sythesised TX module.

Pete

bruce88123

When you make changes like this you must remain in the same BAND. Example: 27 MHz, 72MHz, 35MHz, 50 MHz. I'm not sure you were crossing bands but if you were it won't work even with a synthesizer. You would need to send radio to Mfg or radio shop for alterations.