daven

My Feedback: (1)

Just curious, is anyone aware of a PCM 4 or 5 channel receiver compatable with a Futaba transmitter?

Don't see one either by Futaba or Hitec, any ideas?

Looking for something rather small and light for a fast plane.

XJet

Why does it have to be PCM?

There are a growing number of small, light, reliable and very sophisticated receivers out there now which offer virtually all the benefits of PCM but at a lower cost and with greater compatibility. Some of these receivers offer failsafe capabilities and automatically filter out interference. Others add the ability to respond only to your transmitter's electronic signature, significantly reducing the chances of beign shot down by someone accidentally using the same channel while you're flying.

The newest of the breed even offer fully-synthesized operation such that you can quickly change to any channel with the push of a button or the turn of a few knobs.

PCM is great -- but it's not the only way to get a virtually bullet-proof setup.

BillS

Daven asked about buying only a receiver. I don’t quite understand how the receiver only can respond to the signature of an existing Futaba transmitter. Do all Futaba transmitters transmit a signature? Is only a matter of buying the correct receiver? Would you mind clarifying?

I do understand how TX and RX can be purchased together.

Bill S

Scar

My Feedback: (3)

Actually, he asked about a PCM receiver, specifically. While Futaba, JR, Airtronics and Hitec all offer a PCM version of their product, none of them share their system with the others. Thus, only a Futaba PCM transmitter will operate a Futaba PCM receiver, etc.

I'm wondering why one would want a low channel count PCM receiver, but that's what he asked about.

Best wishes,
Dave Olson

mglavin

My Feedback: (31)

daven


Futaba has a small 8 channel PCM RX on 72mhz available.

As mentioned above, there are alternatives to our tried and true PPM RX's which offer fail-safes, IPD (Intelligent pulse decoding), DSR (digital signal recognition) and or DSP (Digital signal processing).

Essentially these RX's have intelligent signal processing which works pro-actively to keep your model flying glitch free. The RX is able to reconcile an errant pulse train between a valid one by comparing previous valid instructions or positional information. Once confused, the RX will generate a frame to replace a known bad frame, if the inference continues a Fail-safe Setting will take over much like with a PCM RX. Additionally the DSR capable RX's recognize/memorize the pulse train and modulation shift signature of your TX and attempt to ignore other TX's.

What's neat about these RX's is they offer features in line with PCM and work with any PPM TX, some even have auto-shift select capabilities. These Rx’s are also reasonably priced IMO.

Berg, Multiplex and FMA offer this technology in Small footprint RX's currently and its widely utilized and accepted in the electric world.

XJet

They're no longer limited to small electrics and park-fliers though.

I'm using these receivers in much larger planes (.90-sized) where they outperform conventional PPM and in some cases even PCM receivers. It's quite surprising just how good some of these smart receivers are.

As I often say (:-), I can't understand why people continue to buy "dumb" FM/PPM receivers when these smarter alternatives are available for the same (or sometimes even less) money.

daven

My Feedback: (1)

Ok,

Maybe I should have clarified this a bit better. I run both a Futaba 9c and 8uafs with Hitec 555 and Electron 6 receivers. In MOST cases, they are bullet proof in my 170-180 mph racing planes. However, on several ocassions over the past couple of years, I have gotten bad bumps while flying at major national racing events. Not saying this has ever costed me a race, but it scares the crap out of you in the middle of a heat when your plane acts like full down elevator has been applied for about 1/2 a second at these speeds.

The pylon Futaba sponsored guys have recommended the 149 DP PCM receiver, but I struggle spending $160 on a relatively large and heavy receiver for pylon racing. If there was a smaller 4-5 channel PCM (or anything better than what I'm using) receiver, I'd give it a try.

These are very expensive planes, and I never reuse electronics (receivers/switches/and servos) after a crash in my "traveling" planes so I know my equiptment is sound.

Thanks for your comments so far.

mglavin

My Feedback: (31)

To true Jet... but Daven was speifcally looking for a small footprint RX, thus my comments.

Were also using this new technology (although its not that new anymore) in our larger birds... Multiplex offers several IPD RX's standard size and smaller.

We rigged Josh's 39% Aeroworks Extra with MPX's new 12 channel IPD synth RX for the 2004 XFC last year and have been using it ever since... We also have a few large electric with the smaller IPD's.

mglavin

My Feedback: (31)

Dave

The IPD stuff is better than the any standard PPM RX........ In case I wasn't clear these intelligent RX's are running neck and neck with PCM RX's and may even be better in some aspects. read through my comments above and you'll note that this technology affords all the benefits of PCM and then some.

Multiplex the innovator of PCM protocol to the RC world no longer offers PCM and has moved into the future with IPD RX's.

daven

My Feedback: (1)

Michael, so what IPD receiver would you recommend that works with my Futaba transmitters?
I would like to give them a try.

ZAGNUT

My Feedback: (1)

a good start would be the FMA FS8 that only weighs about 15g without all the co-pilot crap.

fully programmable failsafe, scans your frequency for other users before you turn your Tx on, glitch counter that tells you of any interference you had during a flight and also has flight data recording ability with a PC interface.

i love mine!


dave

daven

My Feedback: (1)

Can you buy the FS8 by itself? The way I see it, its about $200.

mglavin

My Feedback: (31)

Dave

Presently the only MPX IPD offerings less the synthesized stuff works with negative shift TX's only, so Futaba is out for now.

Berg and FMA make small foot print RX's.

http://bergent.net/

https://www.fmadirect.com/site/home.htm

ZAGNUT

My Feedback: (1)

yes, the FS8 can be bought without all the extras for $120. go to the "receivers" section on the FMA site.



dave

XJet

The FMA stuff is quite good (I've got three FMA-M5 receivers) but I've found their support to be worse than awful -- they don't even reply to emails directed at the support department. The M5s are cheap enough that I buy them in the full understanding that support is minimal without too much concern. However, when you're spending three or four times as much for a receiver you tend to want a company that responds to support queries.

There are now a raft of IPD/DSP/SMART/etc receivers out there, all with their different strengths and weaknesses.

Perhaps the biggest problem for your application might be the lack of channels

The Sombra Shadow is a newcomer that's looking pretty good and it has the bonus that it's synthesized so you can switch to any legal 72MHz channel in just a few seconds without changing crystals. It's also one of the lightest/smallest of the current crop and their support seems superb so far. The version 1 is 6-channels but their 7-channel model is due out shortly.

The Bergs have a well-deserved reputation for performance and support -- but a maximum of 6 channels can/will be somewhat limiting.

Both the Berg and the Sombra have auto-shift detect which makes them compatible with just about every brand of transmitter (in PPM mode) that's out there. The only incompatibility at this stage is the synthesized Futaba transmitters, although most other brands of synthesized transmitters work just fine apparently.

Both the Berg and Sombra also have something called TSR which effectively locks the receiver onto the characteristics of its specific data-frame. This makes them far more resistant to the effects of another transmitter operating on the same channel. I was skeptical about this but it's incredibly effective.

While all these tech-features sound great, don't underestimate the importance of support either...

I've gotten replies to emails sent to Berg at 9pm on a Sunday evening and questions get answered very promptly, professionally and by someone with great technical ability.

And, while other manufacturers seem to struggle to even acknowledge faults, the guys at Sombra have identified, acknowledged and are making available a fix to a small firmware problem that occured in the first batch of these receivers. I know at least one other major RC manufacturer that, weeks later, still don't have fixes for their firmware woes in multiple products, leaving some users twiddling their thumbs or facing extra expenses to "work around" the problems.

As products become increasingly complex it's unreasonable to expect every new design to be perfect but what counts is the speed and efficiency with which any problems are addressed.

daven

My Feedback: (1)

The limitation of channels is not a problem in my case. What I'm looking for is a rock solid "bullet proof" 5 channel receiver. If it costs a $120, I would be ok with that, I just need something that is going to be perfect. These planes tend to take a beating with midairs, crashes, and rough landings, so anything susecptable to damage from bouncing around will not be ok.

Thanks to everyone who has responded so far. At this point, I haven't found anything better than what I am using.

XJet

There is a wise old saying which suggests that when something is not broken it makes no sense to try and fix it :-)

JohnMac

I am using Multiplex IPD and IPD Synth Rx's in my jets which are even faster (and I suspect even more expensive[]) than your Pylon racers. They also have the added benefit of slightly faster response. They do a relatively small 7 channel IPD Rx at a good price. Only single conversion but no problems with them in my electric models. The jets all have the larger 12 channel double conversion Rx's.
Simprop and Webra also make small IPD Rx's but I am not sure if they are available in the USA.
Regards,

John.

vkmaynard

My Feedback: (1)

Sombra! I just tried mine. I turn on both my TXs on the same channel. The Sombra only responded to the first TX that was turn on! Amazing. It is also dual conversion and weighs only 8g.

Victor

XJet

The TSR on the Sombra and Bergs works surprisingly well and is one of the key areas where these little receivers outperform PCM units by a significant margin.

dirtybird

My Feedback: (5)

A couple of years ago I purchaces a Multiplex IPD receiver that I specified for use with Futaba and they supplied it.

JohnBuckner

My Feedback: (1)

XJet

I am interested in the same applications a Daven and there is nothing worse than carrying around extra baggage like 'channels' or the room to stuff them somewhere.

I have some links for Berg but can,t find anything on Sombra perhaps you have the info?

John

Team Geriatric

ZAGNUT

My Feedback: (1)

are you doubting the advantages the "smart" receivers have over the two you're using right now? i fly in a harsh rf environment and could always count on a couple of glitches per flight with standard ppm receivers, nothing deadly but still no fun. since switching i have had nothing but rock solid performance. the glitch counter shows that i'm still getting hit but i simply don't see it or feel it while flying.


and from what i know the sombra receivers have all been scarfed up and people are waiting for the next production run. the radio forum at RCG has a couple of heavy-duty threads on the subject with plenty of comments from sombra.


dave

BasinBum

My Feedback: (2)

FMA's products are great. Their customer service sucks.

daven

My Feedback: (1)

Actually I am doubting it.

At 24000+ RPM and 180 mph, I need something I can trust. I'm not aware of any pylon racer using these new styles of receivers. NOT that I don't think their capable, I just am not sure I want to be a guinea pig.

I appreciate your suggestions, but there something about the FMA and even the Berg receivers that makes me think they look "cheap" and I'm not sure I am willing to take the risk.

Not trying to be a jerk, just my opinion.

thanks,