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Old Jul 16, 2006, 08:01 AM
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What's a Good JR Radio for Sailplane Application

I nearly had my "mits" on a JR S600 on ebay, but let it get away...

So I want to fly sailplanes, and I was wondering if someone could recomend a nice JR radio system for the job. The plane I have is the 2M variety, hi-start or winch launch.

I own a DX6, but they are not recomended for anything other than PF'ing

Johnnie
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Old Jul 16, 2006, 09:45 AM
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Sailplane transmitter

Buy a JR 9303. It will do everything you want and more for a sailplane. Go to the Horizon Hobbies website and read the manual online and also read Sherman Knights setup guide on the same site.
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Old Jul 16, 2006, 10:00 AM
Jeff Carr
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Joined Mar 2001
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If your looking for an inexpensive radio a JR 8103 is good also. The 9303 is one of the best for Sailplanes but the 8103 will do the job. I see them on here and other sites for 175-200 range.

If cost is not a concern get the 9303

Jeff
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Old Jul 16, 2006, 07:18 PM
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Johnnie---Go to the actual field results thread. There, I am sure, you will find your DX6 will do quite nicely. There are people flying nearly all types of aircraft with great results.
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Old Jul 16, 2006, 07:25 PM
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9303 - About $550 - Great saliplane radio
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Old Jul 16, 2006, 08:43 PM
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Don't use the DX 6 for a two Meter!

The range on the DX6 is NOT adequate for a two meter! It is meant to be flown only in small park plane settings. A two meter sailplane can be flown well beyond the range of the DX6.
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Old Jul 16, 2006, 09:02 PM
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Quote:
Originally Posted by TomLee
Johnnie---Go to the actual field results thread. There, I am sure, you will find your DX6 will do quite nicely. There are people flying nearly all types of aircraft with great results.
DX 6 in a 2M sailplane. Will it work? Yes, if it is balsa or plastic, not covered in white covering or any kind of metallic covering. Otherwise one of these covering can shorten the range or block the signal.

Assuming you have full range, say 1500, or push to 2000 feet, you can fly a 2M sailplane within that range, however it is not hard to get one past that range. I know I have had my Spirit 2M out over 1/2 mile, 2600 feet, which might still work but is beyond the safe/reliable range for this radio.

Generally I don't recommend the DX6 for anything over 60" wing span because it is harder to get it out beyond 2000 feet with good orientation.

If you can be VERY careful, and avoid the situations above, and keep the plane close, you can use the DX6. But I don't recommend it.

I fly RES and Full House Sailplanes of 2-3.6M in wing span. I am a sport flyer who is moving into competitive flying. I fly a Futaba 9C.

If you are going to be flying 3 channel RES type sailplane, almost any 5+ channel computer radio will do. Look for an elevator to flap/spoiler mix for landing. You can use a standard 4 channel radio, but .... why. Computer radios offer so much for such reasonable prices.

If you plan to get into full house gliders, you want at least a 6 channel radio. Jr 6102, JR 7202, Futaba 7C, Optic 6, Airtronics RD6000 Super would be examples.

If you plan to get into competitive flying of full house sailplanes but are on a limited budget, say around $325 or less, you want at least a 7 channel radio that can handle a 4 servo wing, camber control, flight modes and more.

Hitec Eclilpse 7, Futaba 9C Super, Polk Hobbies Tracker III, JR 8103.

If you want the best in sailplane radios for under $1000, then consider the JR 9303, the Airtronics Stylus, the Roal Evo 9.

Over $1000 - have fun!

Hope this is helpful.
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Old Jul 17, 2006, 06:37 AM
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I had contemplated using the DX6 in my 2M plane, but the more I read, the more I find it would be against my better judgement to do so.

Thank you all for the recomendations, but I gotta throw this out there; is the Tower (Futaba) 6-ch computer radio any count? I know it's not JR, but price wise it is handsome.

I have been watching ebay, and there have been some interesting deals on the JR 6 and 8 channel radios.

Johnnie
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Old Jul 17, 2006, 09:11 AM
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Sorry to be a pain, but please read post 7 again and tell us what kind of flying you plan to do and what kind of sailplanes. In the absence of this info, and a budget target, all radios are equally good or equally bad.
http://www.rcgroups.com/forums/showp...31&postcount=7

Gliders/sailplanes are no different from other planes in what it takes to fly them. They are very different in some of the things we do with them to maximize their perfromance.

Are you focused on slope soaring, thermal duration or hand launched/discus launched gliders. Sport
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Old Jul 17, 2006, 11:27 AM
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Quote:
Originally Posted by aeajr
Are you focused on slope soaring, thermal duration or hand launched/discus launched gliders. Sport

The answer here is yes... But when I read that one radio won't do "butterfly" and that radio cannot have channels re-dedicated, or channel swapping etc etc then I get confused on what would be a good all-around radio...in a JR enclosure pre-ferred...but not if the Tower 6-channel computer will work (budget constraints concidered).

Johnnie
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Old Jul 17, 2006, 12:03 PM
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Now we are starting to get to the core of it.

Many of the features you are referencing are high end features in radios that cost many times what a tower radio costs.

You don't need butterfly/crow to fly a sailplane. And it has no application on a R/E or RES,or aileron/elevator sailplanes/slope gliders. You would not use it if these are what you plan to fly.

Unless you plan to focus on thermal duration contest sailplanes, you don't need these high end radios. Nice to have, but not required.

If you are planning for the future, I would recommend you go to at least a midrange sport comptuer radio if you think you will be going to a full house sailplane AND you can invest some extra $$ now.

Again, If you are barely pulling together money for a tower 6 EX, then these GOOD sailplane radios are beyond your budget.

Why would you want to swap channels? You don't NEED to do that, but if you have a higer end radio, many offer this. At about $400+ ( just for the radio. Servos and receiver extra ) a Royal EVO 9 can assign anything to anything!
http://www2.towerhobbies.com/cgi-bin...&I=LXEXV7&P=ML


If you want JR - good all around radio -

JR 6102 - Excellent all around radio. Has no specific sailplane programming. No built in Crow, for example. Will not independently address 4 wing servos, as far as I can determine. But these will not hold you back from flying a full house sailplane.
http://www.horizonhobby.com/Products...odID=JRP6644**

Having said that, most people would find this completely adequate to fly most sailplanes.

A contest pilot would choose the JR 9303. Rich in sailplane features the 9303 is VERY popular with contest sailplane pilots. But most people don't need it! I would love to have a 9303, but the Futaba 9C is adequate for me.
http://www.horizonhobby.com/Products...odID=JRP9240**

[U]For you,/U] the 6102 would be an excellent choice for today and well into the future. Planes, sailplanes, aerobats, Helis, great radio.


Hitec Optic 6 - I am helping a friend set up a competition sailplane on one of these. Not a true sailplane radio, but the Optic does have a number of sailplane specific functions.

Futaba 7C - Like the two above, not a real sailplane radio, but good enough for most people.

The JR 6102, or the Hitec Optic 6 or the Futaba 7C may be all you will ever need, unless you start flying sailplane contests.

However if the money is just not there, I would direct you to the Futaba 6 EXAS. Low cost, all the basics. I will get the job done for sport flying.

What is your facination with JR? Excellent equipment but wondering why this is such a priority.
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Old Jul 17, 2006, 06:06 PM
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Post a "wanted" ad for an 8103. You can get them in good shape for around $200-250.
If you're gonna run a 4-servo wing I wouldn't waste my money on a radio that doesn't fully support it-you'll eventually end up buying one that does.

EDIT- There's one on RCSE now for $225.
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Old Jul 17, 2006, 07:43 PM
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Radios with 4 Servo Wing Support
We are really tossing things around here. but let's keep piling on the info.

As R. Carver said, and as I indicated, the more advanced radios have the ability to address 2 ailerons and two flaps spread across 4 channels without the use of Y cables. When working with high end sailplanes or competition sailplanes, you would want this feature.

We established that hte 9303 and the 8103 can do this. I don't think the 8103 is available new as I can't find it anywhere and it does not come up on the JR web site.

Let's see who else has a radio that handles 4 wing servos, under $1000. There may be other radios that handle 4 servo wings but I know these do it.


Polk Tracker III - 8 Channel - $160
http://www.polkshobby.com/
http://www.rcgroups.com/4259
http://www.rcuniverse.com/magazine/a...article_id=594
8 Channel, 99 model memory, shift select, freq synth, Unique Safety Scanner
to avoid channel conflict, Timer, Exponential, EPA, DR, 4 standard mixes
and 3 user mixes, switch assignability. Package includes one standard size
synth
receiver ( no crystals needed), one standard size servo. I have not tried it
but I understand this radio will support 4 wing servos on 4 individual
channels which can be addressed via user programmable mixes.


Hitec Eclipse 7 - $180 - for the radio
http://www.servocity.com/html/7-ch_eclipse_systems.html
http://www.hitecrcd.com/Radios/eclipse.htm
manual
http://www.hitecrcd.com/product_fs.htm
7 channels - 7 model memory, Shift select, 3 conditional mixes per model,
Channel change module or optional Spectra frequency synth, Five user
programmable mixes, conditional mixes, a variety of predefined mixes.
It is distinguished from the group above in that it has support
for a 4 servo wing and perhaps a mix or two more at $180.
Hitec is also coming out with a 2.4 GHz module for their radios
http://www.rcuniverse.com/forum/m_3986179/tm.htm

Futaba 9C Super - about $290
http://www.futaba-rc.com/radios/futk75.html
http://www.allerc.com/product_info.p...roducts_id=754
http://www.rcgroups.com/links/index.php?id=4600
http://www.servocity.com/html/9ca_super_systems.html

Futaba transmitter feature chart
http://www.futaba-rc.com/radios/feature-compare.html

Futaba 9C Super has replaced the 9C that I own, though some places still
have the 9C. 9C Super has unlimited model memories via removable modules, 7
User programmable Mixes + 8 defined mixes, 4 snap roll programs, two servo
elevator support, 4 servo wing support, customizable trainer program and
switch assignability. This is a very flexible radio.

Unless you have a large budget, I would not consider this a first radio. If
you have outgrown your entry level or intermediate computer radio and want a
significant jump in capabilities, take a look at the Futaba 9C Super.
This is an advanced sport radio, or a budget competition radio, that has
virtually all of the features that advanced sport power and sailplane
pilots are likely to need. It has a very strong following.

Channel Synth module for the 9C and 9C Super
http://www.rcuniverse.com/magazine/a...article_id=542
Hitec is coming out with a 2.4 GHz module for their Optic 6, Prism 7X and
Eclipse 7 as well as the Futaba 9C
http://www.rcuniverse.com/forum/m_3986179/tm.htm

-------------------------------------------

$400 and up for the radio alone

Royal Evo 9 Channel - $520 w/synth module
http://www2.towerhobbies.com/cgi-bin...&I=LXEXV7&P=ML
http://www.multiplexusa.com/Radios/royal-evo-9.htm

Airtronics Stylus - 8 Channel -$440
Optional sailplane card - $120
http://www.nesail.com/detail.php?productID=772
http://www.airtronics.net/stylus.htm

JR 9303 - $450
http://www.horizonhobby.com/Shop/ByC...odID=JRP9269**
reviews
http://www.rcgroups.com/links/index.php?id=4643
http://www.rcuniverse.com/magazine/a...article_id=515


If you have $2200 laying around, check out the Futaba 14MZ
http://www.14mz.com/
http://www2.towerhobbies.com/cgi-bin...&I=LXJHG6&P=ML

What you need to know about receivers:
http://www.rchangout.com/forums/radi...ers-12151.html
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Old Jul 18, 2006, 06:31 AM
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Quote:
Originally Posted by aeajr
However if the money is just not there, I would direct you to the Futaba 6 EXAS. Low cost, all the basics. I will get the job done for sport flying.

What is your facination with JR? Excellent equipment but wondering why this is such a priority.
Facination?

ergonomic - feels better in my hands

...& looks - I like the way they look

Other than that, I have no further experience with JR or any other TX except thru my sons Hitec Flash4...and I have concidered the Flash5 as a possible radio too...but I like the look and feel of the Optic6.


Drilling down deeper, I have no idea what PCM, PPM, neg shift, pos shift, etc etc mean either, so without asking the question which radio do people prefer most...? brand A, B, C...I asked about JR because I chose the brand I thought looked good. I do own the Spektrum DX6 which is a JR in 2.4Ghz clothing. It has way more features than the JR 4-channel that I owned 5 or so years ago, and has been very "park flier" friendly to me. But since I have an attraction for sail planes, I wanted a radio that won't be limiting to me, and wouldn't break the bank for starting out in sail planing with my new 2M.

By limiting: what if I go "full-house" 3M and such...well then I will need to find yet another radio...

Aeajr, your last post could be a sticky...in the proper sail plane forum of course

Good info presented here, looks like I have lots of good research to start with.

edit: How about the Multiplex Cockpit MM 7-channel radio...any good? Found a descent price on the radio NIB

Johnnie
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Old Jul 18, 2006, 07:25 AM
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Quote:
Originally Posted by Johnnierkt
Facination?

ergonomic - feels better in my hands

...& looks - I like the way they look

Other than that, I have no further experience with JR or any other TX except thru my sons Hitec Flash4...and I have concidered the Flash5 as a possible radio too...but I like the look and feel of the Optic6.


Drilling down deeper, I have no idea what PCM, PPM, neg shift, pos shift, etc etc mean either, so without asking the question which radio do people prefer most...? brand A, B, C...I asked about JR because I chose the brand I thought looked good. I do own the Spektrum DX6 which is a JR in 2.4Ghz clothing. It has way more features than the JR 4-channel that I owned 5 or so years ago, and has been very "park flier" friendly to me. But since I have an attraction for sail planes, I wanted a radio that won't be limiting to me, and wouldn't break the bank for starting out in sail planing with my new 2M.
Johnnie
Johnnie,

I would say that any 6 channel radio will fly almost any sailplane that includes flaps. So the question is not, can they fly sailplanes but how advanced do you want to be in your flying. That is what we have been discussing.

Based on your statement above, you would be OK with any 6 channel computer radio. I would advise that you insure you have Flap-elevator mixing to set up a landing mix. I consider that one of the most important mixes. Landing sailplanes can be tricky and flap/elevator or spoiler/elevator mixing can help a lot. You don't have ot have it, but I would recommend it.

Aileron differential and aileron rudder mixing would be good too, but again, not required. They allow the plane to fly more efficently without a lot of set-up on your part and can handle some of the in flight tasks for you.

After that it is all gravy. All those mixes, camber adjustmentsm flight conditions are the hallmark of "sailplane radios". But you don't have to have them to fly sailplanes. They are very useful to the serious sailplane pilot or the competitor, but not required to just have a fun afternoon flying sailplanes. And they are not as actively used on slope.

I don't now the multiplex Cockpit, so I can't help you there.

You commented on shift and the like. Hopefully this will help.


WHAT YOU NEED TO KNOW ABOUT RECEIVERS
by Ed Anderson
aeajr on the forums
Revised 7/13/06

You control the plane by moving controls on the radio, but it is the
receiver that "hears" the radio and directs those commands to the proper
servos to move them according to your wishes. So, what do you need to know about receivers when preparing and flying your plane?


FREQUENCY AND CHANNEL

Receivers are specific to a given frequency. For example, in North America,
NA, our planes can be flown on 27 MHz, 72 Mhz, and perhaps others, but these are the most common. Your receiver has to match the frequency of your radio in order to be able to hear it. In NA 72 MHz is considered the RC aircraft hobby channel it is split into 50 sub frequencies, or channels so that we can have more than one person flying a plane at any given time. In NA, 27 MHz is typically only seen in low end RTF planes and is shared with low end
cars and boats and is limited to 6 channels.

Normally you need to get a crystal with your receiver that matches the
channel of your radio. In RTF packages, this is already done, so you don't
need to worry about it. However if you are buying your own receivers, you
must match them to the frequency and channel of your radio when you buy
them. Your supplier can help you with the details. One suggestion is that
you not mix crystal brands. They may work but this introduces a risk that
you are better off avoiding. If you get a Hitec receiver, get a Hitec
crystal.


AM and FM and FM SHIFT

Just like your car radio, RC radios can use AM or FM to transmit their
instructions to the plane. AM is an older technology but it is still in
use, primarily in low end 2 and 3 channel radios. However most new radios
are FM. Both work!

In North America, FM radios are grouped by those using positive shift and
those that use negative shift. Typically we speak of JR and Airtronics as
positive shift. Hitec and Futaba are negative shift. In some cases these
brands can be made to change shift through a function called shift select or
reverse shift.

Shift refers to how the radio codes instructions for the receiver. One is
not better than the other, they are just different. This is only important
when you are buying a new receiver as you need to be sure that your FM
receiver and your FM radio are using the same shift. Shift does not apply
to AM radios.

Crystals are not specific to shift, but they may be specific to AM vs. FM.
Be sure you get the right type of crystal for your receiver.


FM/PPM and FM/PCM

PPM and PCM further define how the radio codes commands to the receiver. We
normally speak of PPM and PCM in the context of FM radio/receiver
combinations. If you are buying an AM receiver/radio, you don't need to
take this into consideration.

FM receivers can be either PPM or PCM. When people say FM, they typically
mean FM/PPM. If they say PCM, they mean FM/PCM.

As long as the shift is right, you can mix brands of FM/PPM radios and
FM/PPM receivers. On the other hand, FM/PCM receivers are highly brand
specific. If you have a Futaba radio capable of PCM transmission and you
wish to use a PCM receiver, you must have a Futaba PCM receiver that is
compatible with that model radio. No mixing brands in PCM.

As far as I know, all FM radios can transmit in FM/PPM. Some can transmit
in FM/PCM also. I don't know of any that are FM/PCM only, but there may be
one out there. If PCM is listed, it is normally an extra feature, not a
requirement you use PCM.

Some will say that PCM is better and more reliable. I can neither confirm
or dispute this point as I have not used PCM receivers. I will point you to
a couple of articles that discusses PCM, how it works and their opinion
of the advantages.

Futaba FAQ on Advantages of FM/PCM over FM/PPM
http://www.futabarc.com/faq/product-faq.html#q102

Article on PCM vs. PPM
http://www.aerodesign.de/peter/2000/...ml#Anker143602

PCM receivers tend to be more expensive, larger and heavier. From what I
gather FM/PPM is what the overwhelming majority of flyers use. FM/PCM seems
to be most popular in the high performance world, giant scale and
competition planes. Choose whichever you like as either will fly your
plane.

RANGE

For practical purposes, range is determined by the receiver, not the radio.
It is a function of sensitivity of the receiver and its ability to pick out
the radio signal and filter out noise. Many brands state the rated range of
their receivers. Some do not. I suggest you stick with brands that state
their rated range or you could end up flying beyond the range of your
receiver.

How much range is enough? That depends on the application. You can
NEVER have too much range, but you can have too little. If the plane
gets out of range it will crash or fly away. More range is always better.

Here are my suggestions for minimums:

Indoors

Indoor planes are usually very weight sensitive, every gram counts.
To get extremely light weigh, sometimes range has to be sacrificed but that
is OK indoors as long as you know what it is. I suggest 200' minimum and
more is better but you may be fine with less. Many indoor flying spaces are
less than 100 feet along any span and you are not going to accidentally fly
past the walls.


Outdoor - Planes

Slowflyers, micro helis and small electric planes under 36" wing spans can
often get by with ultra light receivers with ranges of as little as 500
feet. This is adequate if you have a small model or fly in a small field of
under 500 feet in span. Many of these small models can be hard to see at
ranges of more than 350 feet, approximately the length of a football field.
I prefer more range, but many people do fine with 500 foot receivers. The
GWS pico 4 channel is a good example of this kind of receiver.

Today there are plenty of micro receivers with 1000' or greater rated range
that are under 1/3 ounce, about 9 grams. I have a large field that is 1600
feet long so it is easy for me to get a plane out beyond 500 feet without
realizing it. While it can become hard to see them at that range, I don't
want to lose it because I ran out of receiver range.

If you can tolerate up to 1/2 ounce, about 14 grams, for your receiver, then
there is no reason to use a receiver with a 500 foot range limit, except
price. The Spektrum DX6 receivers are good examples. Tiny in size they are
a safe working range of 1500 to 2000 feet. The Hitec Micro 05S at .3 oz,
about 8 grams, has a range of 1 mile. Berg, FMA Direct and others make tiny
receivers with over 1500' range ratings. Why limit yourself with short
range receivers and take a chance of losing you model?

For gliders, sailplanes, fast electrics or glow planes with wing spans of 2
meters, about 80 inches or less, I recommend a minimum of 2600 feet, 1/2
mile or 1 KM depending on how your receiver specs are given. More is ALWAYS
better.

Planes with greater than 2 Meters or 80 inches, and especially thermal
duration sailplanes, I recommend you use a receiver with a 1 mile, 1.5 KM or
5000 foot + rating. It is quite easy to get these planes out 3/4 of a mile,
especially the larger sailplanes, and you don't want to have signal problems
with a plane this large that is out that far. This will give you good
signal strength for the likely distance you will fly the plane which is
probably no more than 75% of that range.


SIGNAL PROCESSING - Single and Dual Conversion, DSP and more

In addition to range, receivers will usually specify if they are single
conversion, dual conversion, or that they use some other method of signal
processing. I will leave it to the engineers to go into depth here.
However, as a general rule, dual conversion is better than single but there
are excellent single conversion receivers that have digital signal
processing and other ways of making sure they pick up the right signal.

I have no hesitation to use single conversion receivers with 2600 foot, (
1KM or .6 mile) rated ranges in my models that will be flown less than 1500
feet out. Most of my electric planes can't be easily flown further than
that and
since I am operating at less than 70% the raged range I feel comfortable
that good quality single conversion receivers should be fine.

For my 2 meter and greater wing span planes, I use only dual conversion
receivers. Here I am flying planes, typically sailplanes, that may be over
1/2 mile out and 1000 feet or more in altitude. I need every bit of signal
processing I can get to insure I get clean control. I can't afford even a
single glitch.

You make decisions based on your type of flying. This is what I do.

Some receiver brands offer single conversion, dual conversion and perhaps
other types of receivers. Be sure you get the right kind of crystal based
on the receiver. For example, Hitec dual conversion receivers and single
conversion receivers take different types of crystals. I don't know what
makes them different but you can not interchange them. They won't work.


CHANNELS

We spoke of channels above in terms of frequency. We also use the word
channels to describe how many servos/devices you can control. So a 4
channel radio can control up to 4 devices, for example. It is OK to have
more channels in the receiver than your radio has as some slots are used for
things other than channel control. For example, if we have a 4 channel
radio and are flying a 4 channel plane your slots might be used like this:

1 per control channel = 4
1 receiver battery
1 for plane locator or battery monitor

In this case you might want a 6 channel receiver to give you 6 slots. Or you
can use one or more Y cables to share slots. However I prefer to have a
receiver with extra slots rather than use Y cables. I feel it will give me
greater reliability. Rather than putting money into Y cables I would rather
put the money into the receiver.

If you have a 3 channel electric plane, you need a minimum of a 3
channel receiver. You don't typically need a separate slot for a receiver
battery as your electronic speed control normally provides the receiver with
battery power from your motor battery. You can use a 3, 4, 5, X channel
receiver, but it must have at least 3 channels.

You can also use a 2 or 3 channel receiver with a 4 or more channel radio,
but you will only have 2 or 3 channels of control available. An example
might be to use a 3 channel receiver for your R/E/T plane but use a 4
channel radio to fly it. That works!


COMPUTER RADIO AND CHANNEL MIXES

If you are splitting functions using mixes in a computer radio your
receiver may need more channels. For example, if you have a computer
radio, you might be able to use two servos for your ailerons and have each
work from its own channel. Each aileron will be controlled its own channel.
Some radios can put the second aileron on any channel and some require they
be on specific channels. Consult your manual for guidance here.

Here is an example where we use more than one slot for a function because we
have individual servos on each surface. This is the layout of one of my
gliders and is controlled from my Futaba 9C computer radio. I use an 8
channel receiver and 7 servos.

Ailerons - channels 1 & 7
Flaps - channels 5 & 6
Elevator - channel 2
Rudder - channel 4
Tow hook release Channel 8
Battery - uses channel 3 slot
Plane Locator - Shares channel 8 slot with the tow hood release servo
via a Y cable


Summary

The receiver is the most critical of all the electronics you will put in
your plane. The most expensive radio with the wildest features is just a
paperweight without a good receiver to carry out its instructions. While
the terms can be confusing at first, you should now be prepared to choose
a receiver with confidence. Remember to always consult your radio manual
for any specific needs of your radio system.

A key point is that it is the receiver and not the radio that really
dictates the range you can expect. I encourage you to be very aware of the
range rating of your receivers so you don't lose a plane by exceeding your
safe range.

Your receiver has to have enough channels to accept commands from your radio
and to accommodate the number of servos/devices you have in the plane.
However the number of channels in the receiver does not have to match the
number in your radio.

Your receiver needs to match your radio in the areas of shift, frequency and
channel as well as FM/PPM or FM/PCM features. For FM/PPM you can mix and
match receiver brands, but with FM/PCM you can't!

That's about it. Treat your receivers with care and they will take care of
your planes for years to come!

Good article on radios by the Torrey Pines Gulls Web Site.
http://www.torreypinesgulls.org/Radios.htm
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Last edited by aeajr; Jul 18, 2006 at 07:49 AM.
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