Gidday all, I have a JR XF631 and am buying a JR quattro. Can I make my own trainer cord for these radios? Is it just a matter of two plugs and a lead or is there some electronic components involved? I'd appreciate any input. Kind regards, John.

Hmmm....

I dunno about JR, but the buddy cord for my Airtronics was just a cable... no electronics involved... and since it didn't matter which end you plugged into which radio, I can only assume it was a straight through cable...

They really are not that expensive I would just buy one.

I think they are about $30 aussie dollars to buy and if it is just 2 plugs and some wire well I'd rather make me own and spend that on something I can't make. John.

Then I'd say do it.

Just make sure the wires connect to the same slots/pins in the plug.
Dennis-

Thanks Fellas, I'll give it a go then. Any ideas on the length it has to be? I'm also wondering how the signal for all the channels can be transmitted through only a + and - lead or is there more then 2 wires? Kind regards, John.

People will do any thing to save a $1.00 and loose a plane !!!!!!!! Buy a cord.
we were shot down!

Outlaw can you be more specific, is there more to it then a couple of plugs and a lead? Why were you shot down, Did you make a lead and it never worked? If it's as easy as I hope, then I have enough confidence in myself for it to work. I and many others build entire models, install all the components for them to fly then go fly them. Surely there's more risk in something going wrong with that then a simple lead. Outlaw, can you tell me the length of your trainer lead please. Kind regards, John.

I was not shot down but if you wire one wire wrong you are going to have a problem. Most radios are wired different, you have to know what you are doing or you will have a mess!!!!!! With you choice you would get by but make sure you wire the same on both ends. The shot down is when you get to the field and , WELL
SH!@#t
Cables do not cost that much, I do not know where the $30.00 came from.

I use a hitec, and it even tell you which end to pug in to what.

Heh heh, no offence mate but I find you very hard to understand. However, I'll wait for some responses from others before making up my mind. I don't know if you noticed but I live in Australia and the cost for a cord is $28.95 aussie dollars. Thanks for your help outlaw, I think. Regards, John.

I've found this article http://www.uoguelph.ca/~antoon/gadgets/jrfm.htm and it does look rather simple. I will have a go and tell you the results. Kind regards, John.

I make all types of cables "in theUS Army's phone company.....maybe we make crap just to get by on..LOL" . Sometimes i just guess at it and it works after I test it. I would not see a problem with it if you take the time and find a wire dig. or look and a friends cable with a Muil. meter Test it on the ground 1st.... or you can buy one to have that warm fuzzy feeling.......Dang i ramble on late at night[X(]

Chris

A JR trainer cord is very simple... just a couple mini plugs and an appropriate length of 2 lead stranded wire(like servo wire). Solder the leads to the same terminal lugs on the each mini plugs and go use it. I made mine because I lost the original and I am too cheap to spend even $10 on a factory cord. I cannot coment on making trainer cords for other brands, but JR is simple enough for even a novice to build. I have used mine hundreds of times without a single problem. Good luck!

Dan

I tend to like about 5 feet of cable. If you get it too long, you are stepping on it and pull it out. Too short, and you have to stand right on top of each other. I think the futaba had 6 pins but don't remember right now. Yours will probably be different. Some radios require you to plug it in a certain way. Make sure yours is not one of those. Other than that, it shouldnt be that hard.

DMeyer and Flyboy are correct.

The JR is a standard type cable, used in other electronic applications. No problem using an off-the-shelf cable. Or, if you have the skill to make cables, by all means go ahead. Hitec, Futaba & Airtronics are a different story, and yes, the Hitec cable has a specific end for the instructor's transmitter.

And yes, 5 or 6 feet of cable is sufficient. With more cable, you can step on it pretty easy.

Best wishes for success in your training!
Dave Olson

Thanks for the input fellas. I think I can handle the task no probs. I will go with the shielded wire, using the centre wire for the centre pin and the shielding for the earth. This link shows how straight forward the job will be. http://www.uoguelph.ca/~antoon/gadgets/jrfm.htm Does anyone know the size of the plugs? Kind regards, John

Go to the website
http://users.belgacom.net/TX2TX/

there is a lot of good information for making up buddy cords! If you can solder ok and are used to making this kind of thing it is dead easy!

I agree with keeping the cable short - the long cables are always getting underfoot - make sure the expert/teacher always has the "master" tx so that if the cable is accidentally pulled out the teacher always has control ! Seen it happen where the teacher configured his TX as slave (because as one would expect, the puplil's TX was the TX for the aeroplane being used) " when you want me to take over just flick that switch and hold it"........ yep except the buddy cord had been pulled out !!

The buddy box (pupils tx) should always have the crystal pulled out so it cannot emit rf!

John Flynn
The plug that you need is a 3.5mm...

Tell me your joking! Has someone really ever done it this way so that the student has to throw the switch? I have never heard of that. That would have to be the most unsafe thing I have ever heard of if it is true. The student gets into trouble, and the instructor is yelling "throw the switch, throw the switch" and the student can't figure out what to do as the airplane flys into the pits. Man, that would be one instructor that should not be teaching. The student should always be on the second radio.

Thanks Danny, I have a couple of those, however they are 3 field plugs. I'll use the center one for signal, the second for neg and make the 3rd redundant. My new second hand radio will be here by tuesday I hope (JR quatro, ebay special). Apperantly it doesn't have digi trims but this should'nt be a prob. I'll be trying everything on the ground before flying. Although it's not stated by JR's manual, It's good advice to remove the crystal from the buddy box and I will but it's not a prob cause it's only myself and my dad that fly at the field. Anyhow thanks for all the input fellas. I'll let you know how it all goes. Kind regarrds, John.

Just letting you all know that the lead works fine. This buddy sytem is a breeze. Up until now my dad and I where handing the transmitter back and forth. There where some hairy moments but I always maintained plenty of height for recovery. Dad is now taking off and fllying circuits. Thanks for all your input fellas. Kind regards, John.

Glad to hear that everything is going great for you and your dad, may you have many happy flights and even more happier landings....

Makes you feel good to accomplish what others doubted, but given the plug ends it had to have been pretty easy[sm=thumbup.gif] [&:]