Frequency hogs
 

Hi. I have 40 channel frequency TX/RX [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXVW08**&P=7]see it here[/link]. There is another pilot with the same frequency at my local airfield. I swear he must live there because every time I fly he is there. Is buying a new TX/RX the only way to get another channel? Would I need new servos too? Are radios available that can switch channels?
Thanks.

RE: Frequency hogs
 

First of all, you mean your radio is on Channel 40, right?

No, you CANNOT change TX channels, it's illegal. That means you must either get together with the other guy and alternate (your club should have a frequency control panel of some sort), or you must buy another transmitter. The servo's don't matter, but the RX must match the TX.

There are some that are 'synthesized' in that you can select your operating frequency. Polk, Hitec, for example make synthesized models. I'm sure that there are others.

Another thought is the Specktrum DX7 Radio System. It operates in the 2.4 GHz range and will not intefere with others even other DX7 users. It costs about $350 for an entire system (servo's TX, RX, charger) and the servos you are using now are compatible (they will work with the DX7).

DS.

RE: Frequency hogs
 

Thanks for the reply.

Yes, I meant the radio is on channel 40. The other pilot and I alternate turns flying. It is just a bit of a pain waiting 10-15 minutes when we are the only two flyers at the field.

So the receiver is considered to be on "channel 40" as well? So I would need a new transmitter and a receiver, but I wouldn't need to touch the servos. Just plug them into the new receiver.

RE: Frequency hogs
 

Even though he is there, he cannot fly the entire time. Politely mention you would like to take turns since you are on the same frequency. I have heard that most clubs have limits to keeping the frequency pins. The one I used to belong to had a rule where you had to give it up in 15 minutes if there were others on the same frequency/channel.

There are newer radios that use what's called "Spread Spectrum" which means they do not use a frequency like the radio you have. I mean you do not have to declare you're flying on channel XX and see if anyone else is on the same channel. It's more complicated than that so search for the phrase on the internet and you will see what I mean. Since you already have the radio and receiver, I'd go with the "let's take turns" approach.

Good Luck!


-----
You must have posted just before I did...

You are right about the servos just plugging into the receiver. Your current radio sends signals on channel 40 so your receiver my be programmed to receive on channel 40. The servo's don't care what channel you use.

RE: Frequency hogs
 

That's correct. And, in most cases, if you stick with brands (Futaba for instance), you can re-crystalize the RX which is legal, and have an additional RX.

I have an Airtronics RD8000 system on channel 11 as well as the new Specktrum DX7. There is only one other guy in our club that uses channel 11, we don't often clash. But I am in the process of moving everything over to the DX7 system. I've done three so far. I really like the new system, but am still using the "older" RD8000. But, again, the new technology costs $350.00 to get started. New RX's are retailing for $99.00 each.

So, if you are not willing to part with the $$$$ then you will have to work out a compromise with the other guy. Our club rules state that the frequency pin is supposed to be returned to the frequency panel when the pin is not actually in use. That way someone else can use it when and if necessary.

DS.

RE: Frequency hogs
 

You have a couple options

Change your frequency..
Send your TX and Rx to Radio South.. they can change your frequency for about $50
http://www.radiosouthrc.com/radio_repair.htm

Get a new TX on a new frequency..
Your Tx has been discontinued.. This is the new model for $170
http://www2.towerhobbies.com/cgi-bin...I=LXHYK7**&P=0

One advantage here is if you stick with a frequency between Ch36 and 60 (high band) you can put a new crystal in your current Rx (thats legal for you to do) and use it with the new Tx.. plus you have a whole new set of servos for a 2nd plane. The 6EX has 6 model memory so you can use it with multiple aircraft.

Step up to the 2.4gig 6EX for $219
http://www2.towerhobbies.com/cgi-bin...?&I=LXPZT8&P=0
this kit gives you a new Tx and Rx.. you re-use all your servos, batteries and switches.

your old Rx will not work with it.. maybe you could recover some $$ by selling the old Tx/RX as a set.

RE: Frequency hogs
 

You do NOT need a NEW transmitter. You can have an authorized service center change the crystal for you and perform any necessary retuning/checks required. First step is to poll your club to find out what channels are in use so you can request a currently unused channel or a more lightly used channel.
It IS legal for YOU to change RX crystals and you can do this yourself. One condition exists on this IF using Futaba radios. Most of their RX are Hi/Lo band segregated and crystals must be swapped within the same "range" of the band. If you move accross the band you should also send the RX in for retuning. Futaba's latest RX do not have this limitation.

RE: Frequency hogs
 

so, you're telling us that changing tx chrystals is illegal? i wonder why that is? is it because of the tuning that's involved? i dont understand.

RE: Frequency hogs
 

While Changing the Tx crystal will appear to work you may have reduced range and cause interference on other channels.

More info
http://www.bergent.net/crystals.html


More From the Futaba Site

For a unit with crystals: We CANNOT recommend changing crystals to a different frequency. Changing the crystal on your transmitter is illegal unless you have the proper license. The FCC has established guidelines for the modeler's safety and for the safety of spectators. For safety and FCC reasons we must request that both TX and RX be sent to the service center to ensure proper crystal change and retuning to the new frequency. Crystal based radios cannot be converted to another band without parts replacement, and may not be able to be converted at all. Certain radios can be converted, for example, from 72 to 75MHz. Please contact the service center for any other conversions.

The applicable Federal Regulation is as follows:

TITLE 47—TELECOMMUNICATION COMMISSION (CONTINUED)
PART 95—PERSONAL RADIO SERVICES

Subpart E—Technical Regulations
Sec. 95.645 Control accessibility.
(a) No control, switch or other type of adjustment which, when
manipulated, can result in a violation of the rules shall be accessible
from the transmitter operating panel or from exterior of the transmitter
enclosure.

(b) An R/C transmitter which incorporates plug-in frequency
determining modules which are changed by the user must be certificated
with the modules. Each module must contain all of the frequency
determining circuitry including the oscillator. Plug-in crystals are not
considered modules and must not be accessible to the user.

RE: Frequency hogs
 

Crystals? Are we talking about things similar to what Superman used in his ice palace or Napolean Dynamite used in his time machine?

RE: Frequency hogs
 

Actually, Yes to the Superman version. But on a much smaller scale of course. think of them as a precision cut rock. Unfortunately it is hard to cut a rock exactly to the proper size and there are other components in the TX circuit that may need to be tuned to match for best performance. zIt is more critical with the TX than the RX because it is radiating a signal that must be controlled.
Don't know who this Napolean Dynamite is supposed to be.

RE: Frequency hogs
 

Old erroneous discussion.


The 7202 has a FREQUENCY module.... that thing tha pops out in the back.

Just get a new one with the right crystal pre-installed to do this legally.... yes legally.



That said all the seller does is pop in the right crystal and send it to you, but it's then their problem not yours...


To do it "correctly" send the radio to the JR service center and have them change the module/crystal for you. They will double check the module tuning as per FCC guidelines.


Another even better but more expensive option, is to purchase the new synth TX module...

Yes it WORKS in your radio... I have one in my 7202 and I interchange it with my 10X radio and also into a 347 and 728 radio...

That little module can "dial" any channel you wish... very nice for 99.00.

Then just change the crystal in the RX and have at it.

I keep a couple of modules with me in the at the field for quick changes.

RE: Frequency hogs
 

ok, i thought that was why you're not supposed to change tx crystals. thanks for clearing this up.

RE: Frequency hogs
 

That's just it, you are NOT really changing the crystals... you are changing the tuning module that has the crystal installed which is why you can LEGALLY do this. You are effectively changing out the whole transmitter section of the radio.

JR Services can retune the module or swap modules for you. I find their prices fairly reasonable...

However that synth module is very nice and it works very well on your radio.

BTW: when was the backup battery changed on your radio?

It's getting a little long in the tooth, and while they work and will continue to work great the battery has a 2-3 year lifespan.

Send it to JR for replacement. They charge about 10.00 for this.... money well spent if you've ever tried to change it yourself... ( ask me how I know... ) .

RE: Frequency hogs
 

Yes, the owner can change modules opjose but what makes you think that he has a 7202 or any other radio with a module? Nothing about it in this thread.
There are, of course, several manufacturers that produce radios that either have internal synthesizers or have standard or synthesized modules available. We were trying to keep the costs down here I thought otherwise I would have recommended a 2.4 GHz system.

Again, just get your crystal changed at a shop.

RE: Frequency hogs
 

I used to have a channel 44 buddy, he always seemed to be at the field when I was or maybe I was always at the field when he was.
After a while we started greeting each other as "channel 44 buddy".
We shared the pin and there was never a problem and we both flew our planes alot.
I can see how it could be a problem if someone does not want to play nice, but fortunately in my case we were both very willing to share.

RE: Frequency hogs
 

Grr Forum dyslexia strikes again.

That's what I get for having multiple windows open to RCUniverse at the same time... tsk tsk, my bad.

RE: Frequency hogs
 

See if your club has a list of popular frequencies. You can then pick one that doesn;t seem to get used much.

RE: Frequency hogs
 

Just wondering if I'd missed something.

RE: Frequency hogs
 

i never knew it was illegal. Does it also imply to 27mhz and 75mhz?[sm=confused.gif] I have changed my TX crystals before!.........now i know better.[sm=bananahead.gif]

RE: Frequency hogs
 

when a service center changes freq. the transmitter is also electronicly verified to make sure the signal is correct and at the strength required for the unit to function properly, if its not, and the plane is out of range or poss. worse out of control thats where problems starts ie: crashing into the ground or worse into somone with the potental for a fatality.
when I purched my first ARF when the operator asked me( tower hobbies) what freq. did I want, my reply was whats the least popular freq.
so far at my club only one other member flys ch. 50 and he flys on sat.
usually sun is my day so there is no conflict but we also have a 15-20 min rule that says if your flying on a freq. and another club member shares that # then you have to surender the pin and place your transmitter in the impound until his/her time is up the rules are a guide and as long as the persons sharing the pin work out the time then the rule is very flexable until a pin hog trys to monopolize, then the rule book comes out and that ends any disagreement before it starts.

RE: Frequency hogs
 

Short answer - Yes.

Long answer - Yes, it basically applies to all transmitters of this general type above certain power levels. Our transmitters are all above those power levels. Some Park Flyers MIGHT not be required. I can not give a difinitive answer on that. I suggest you contact the mfg about that and ask.

RE: Frequency hogs
 

I CAN'T WAIT FOR 2.4 GHZ modules that are actually AVAILABLE and not just a promise!!!

Until then, I have a synth module and a set of crystals, (about 7 or 8 channels), so I can change the frequency and fly with no conflict, at the field... I seldom need to, but it's nice to have.

RE: Frequency hogs
 

If you have a Futaba, you can check their website on what freqs you can change.

RE: Frequency hogs
 

The 7202 Does NOT have a module. It is a fully synthesized radio, but has NO interchangeable module. JR does not sell a 7 channel radio that is module based. Period. Having said that, why would it need a module if it is synthesized? There is nothing on the back of the JR 7202 that will pop out.

Now, having cleared that up. As stated before, he doesn't have the 7202 anyway.