35mhz Transmitter question

[pchristy]

For your requirements, a pack of Sanyo Eneloops should be more than adequate - for example:

Sanyo Eneloop 2000 4.8v AA Nimh RX Flat, overlander, batteries, helicopters, chargers, wires, remote control, helicopters, power packs, speed controllers | Overlander Batteries

(square packs should also be available, if those will fit better)

I would also strongly recommend the use of a decent "peak-detect" charger for both transmitter and receiver, rather than a "trickle charger". I would also recommend replacing the receiver switch harness as a precaution. Try and get JR heavy duty one which has a separate charge lead (ie: not a socket built into the switch).

Make sure the receiver crystal is properly secured - tape over it with insulating tape if necessary!

Check the servos carefully! Don't just bang the sticks from end to end - move them *slowly* from end to end, watching for any sticky or twitchy points. If in doubt, change the servo (they'll be quite old by now). Make sure nothing is binding at all control extremes. Kyosho's used to have a reputation for high wear on the ball links, though this may have been fixed by the time of the Nexus, but make sure all the control links are secure, and don't detach too easily!

There's really far too much to check to give guidance on a forum like this, which is why I suggest you try and find someone local to give you a hand!

Best of Luck!

[Guest]

I never stated that the 35Mhz had a short range, the short range comes from the PPM module and more specific the NET-127AH which is a PPM system using a single side shift module and receiver, this is where the range problem stems from. The single side shift was an old technique that they used in the JR pulse module, however you can get hold of a NET J35P type module that will definately work with those receivers which elimates the problem. It is just much easier to purchase a new radio.

[cjcj1949]

I've not heard of single side shift. Perhaps I know it by another name. I remember Bessel functions, mainly as something I didn't understand. I used a Jr rx for a few years until it got destroyed and I was very impressed with it. That was ppm, the tx was Futaba. I then replaced the rx with a Futaba PCM which is very good and has good failsafe. The rx recovers almost instantly from loss of tx if you switchit off to test it. It doesn't have to look for a signal it knows where it should be. It is strange how often someone would turn up with the same frequency though. I'm not sure how people do failsafe on a nitro, I've heard mention of return springs, but that would only work with analogue servos.

[cjcj1949]

It was the single side shift I wanted to know about. I don't want to remember Bessel Functions, but I believe they were used to express the energy distribution of the sidebands generated during frequency modulation, and hence the bandwidth necessary to contain a given amount of information. It sort of makes sense now. We always seemed to have to solve differential equations, there was usually some way of cheating given to us by real maths people.