JR R922 9 Channel PowerSafe

[JesusFreak]

I know this is new, but is anyone familiar with this receiver?

http://www.horizonhobby.com/Products/TechnicalSpecs.aspx?ProdID=JRPR922

I'm wondering if it provides voltage regulation as it allows a 6 to 10volt redundant input power source.

[DavidH]

From just reading the literature I would think it is just a reciever with heavy duty connections. I think you will still need to regulate both inputs to the voltage you plan on using. Since it specifically mentions giant scale airplanes and jets. That is why it mentions the 6v to 10 volt operating range. Some of those guys use 8.4 volts and don't regulate it. So I would think you need to regulate both inputs to the voltage you plan on using.

David

[JesusFreak]

David:

I fly large planes. Most of the servoes on the market are only good to 6volts. I use 7.4 volt lipos with a regulator currently, but it would be nice to get it all in once nice package from a top company like JR. Much more then 6 volts will fry almost every digital servo on the market at the moment, though there are rumors of high volt units from Spektrum JR.

Cheers!
Lee

[Pinecone]

JR 8717s work fine on 8.4 volts. :)

[JesusFreak]

JR 8717s work fine on 8.4 volts. :)


I only see mention of 6 volts on the horizon site. Do you have some official reference for higher input on these? I use the 8711s on one of my large gas planes (regulated to 6v). Nice servos. Haven't gone that far on my Helis. I try to keep them light weight, and these are not light servos.

Cheers!
Lee

[Pinecone]

Bunches of people are running them on 8.4v on helis.

[JesusFreak]

Bunches of people are running them on 8.4v on helis.

Ah, so they are "Bunch certified", I understand. LOL.

My experience with running servos higher then rated is that it can lead to shortened servo life. I think things are changing so, who knows, they maybe fine, but I'd like to have the OK from JR/Horizon.

Regards,
Lee

[DavidH]

I only see mention of 6 volts on the horizon site. Do you have some official reference for higher input on these? I use the 8711s on one of my large gas planes (regulated to 6v). Nice servos. Haven't gone that far on my Helis. I try to keep them light weight, and these are not light servos.

Cheers!
Lee

Lee,
I don't think Futaba or JR is going to put the specs on there servos that they will operate at more than 6 volts. But as mentioned, I also know plenty of pilots that are running there servos on unregulated 2S Lithium type batteries where they be Ion or Polymer. That is 8.4 volts when fully charged.
I know a few pilots using tail servos that are rated at 4.8 volts on a regulated 6 volts. No problems with them.

David

[JesusFreak]

Lee,
I don't think Futaba or JR is going to put the specs on there servos that they will operate at more than 6 volts. But as mentioned, I also know plenty of pilots that are running there servos on unregulated 2S Lithium type batteries where they be Ion or Polymer. That is 8.4 volts when fully charged.
I know a few pilots using tail servos that are rated at 4.8 volts on a regulated 6 volts. No problems with them.

David

I know lots of guys that run Nitrous in their street cars too, but when the engine goes "boom", Chevy doesn't want to hear about it. LOL. I like good quality, high performance equipment, but I try to stick to what the manufact. recommends so I have a reasonable chance of the product working as intended and getting warranty support when required. Some guys have money to burn, and can afford to be less cautious. I tend to be a little bit of a stick in the mud and live within the margins. Not always the most exciting, but not the most expensive either. ;-)

I sent a note to Horizon on these large servos to see what they have to say about running at higher voltages. Some times "official" specs. are under rated, and that's fine as long as I can get confirmation from someone with appropriate insight.

Regards,
Lee

[DavidH]

Here you go.
Mike McConville works for Horizon and flies JR and uses there servos. Read the thread and you will see he is using 2S Lipo packs to power the recievers. That is 8.4 volts directly to the servos.
http://www.rcuniverse.com/forum/m_6506891/tm.htm

David

[JesusFreak]

Here you go.
Mike McConville works for Horizon and flies JR and uses there servos. Read the thread and you will see he is using 2S Lipo packs to power the recievers. That is 8.4 volts directly to the servos.
http://www.rcuniverse.com/forum/m_6506891/tm.htm

David

David:

I read through thread. I see he is using two lipos, but he does not mention whether he uses a regulator or not. I run 2 lipos (3 total) on my large scale planes, but with a regulator. I posted a question asking directly.

Regards,
Lee

[JesusFreak]

FYI, I did correspond with Mike, and he quote "has experimented both ways".

I sent a note to Horizon, and they said they only recommend up to 6volts on current JR Servos. Anything beyond that is at your own risk.

Regards,
Lee

[DavidH]

FYI, I did correspond with Mike, and he quote "has experimented both ways".

I sent a note to Horizon, and they said they only recommend up to 6volts on current JR Servos. Anything beyond that is at your own risk.

Regards,
Lee


Like I said earlier. Horizon or Mike since he works for Horizon. They are not going to tell you any different than what JR states in there specs. But I can assure you there is many pilots out there in the giant scale plane part of the hobby using straight 8.4 volts to power there electronics. There is also some in the helicopter part of the hobby.

I will give you an example, the 12 FG transmitter comes with a 7.2 volt nimh battery. Hobbico says that is only battery that will work in transmitter. Yet there is good number of them being used with a 7.4 volt LiPO or Li-Ion battery. No manufactuer is going to tell you something will work that is not in the specs. But yet there is plenty of the employees and team pilots that go outside the specs with no problems.

David

[mjws]

From what I've seen on FG most of the GS guys running 8.4V on 8711's and 5955's found them to run a little hot. A few have found even just knocking them down half a volt helps. Long sustained knife edge and other moves can put heavy loads on for relatively long durations.

On the heli's I think we are in such utter and complete overkill with these servos and the duty cycle is so peaky that they are happy as can be. It's more than a 'few' guys having success running them direct on heli's.

We got the 9100's (922) into the shop early this week. Looks like there is provision for an electronic switch as well that fails closed like pin/flag. Very nice. Haven't had a chance to put one to work yet (-20C here). For me these are magic on 2s A123's for the GS planes. Plug and play high current.

Mike

[JesusFreak]

Like I said earlier. Horizon or Mike since he works for Horizon. They are not going to tell you any different than what JR states in there specs. But I can assure you there is many pilots out there in the giant scale plane part of the hobby using straight 8.4 volts to power there electronics. There is also some in the helicopter part of the hobby.

I will give you an example, the 12 FG transmitter comes with a 7.2 volt nimh battery. Hobbico says that is only battery that will work in transmitter. Yet there is good number of them being used with a 7.4 volt LiPO or Li-Ion battery. No manufactuer is going to tell you something will work that is not in the specs. But yet there is plenty of the employees and team pilots that go outside the specs with no problems.

David


There's a big difference between going from 7.2 to 7.4 (well within nominal voltages of the packs), vs. going 6 to 8.4. I understand that they may be used successfully, but I personally want to know I can get $100+ servos repaired under warranty if their is an issue. That said, I'm looking forward to the manufactures actually making Servos rated at the higher voltages, so we can do away with these silly heat producing, energy sapping regulators. ;-) But to each his own. As long as your having fun and the wife isn't killing you for buying too many $100 servos, that's all that matters. LOL.

Cheers!
Lee

[JesusFreak]

From what I've seen on FG most of the GS guys running 8.4V on 8711's and 5955's found them to run a little hot. A few have found even just knocking them down half a volt helps. Long sustained knife edge and other moves can put heavy loads on for relatively long durations.

On the heli's I think we are in such utter and complete overkill with these servos and the duty cycle is so peaky that they are happy as can be. It's more than a 'few' guys having success running them direct on heli's.

We got the 9100's (922) into the shop early this week. Looks like there is provision for an electronic switch as well that fails closed like pin/flag. Very nice. Haven't had a chance to put one to work yet (-20C here). For me these are magic on 2s A123's for the GS planes. Plug and play high current.

Mike

I'm going to use 922s on my large planes for sure. Overkill for E-Helis. They look like a nice setup.