27mhz to 2.4ghz?

highflying

Senior Member
I have an old 27mhz radio, from Heng Long. They make tanks. I bought it for an exuberant price from my brother. I want to upgrade it to 2.4ghz system, with ease. All I have done is cleaned the internals, and remove the spring that resets the throttle to 50%. Can anyone give any advice or tips, or even if it can't be done at all. If anyone would like to see, these are pictures of the RX and TX.
 

Epitaph

Ebil Filleh Pega-Bat ^.^
Mentor
There are internal modules you can get from Hobbyking by either Assan, Corona, FrSky or Orange that you connect them internally and they modulate the signal through the 2.4 encoder to transmit it. I would recommend either the FrSky as it has a very good protocol (ACCST) with telemetry even and the receivers are easy to find in the UK, or the Orange one which uses DSM2/DSMX, for which the receivers are dirt cheam from Hobbyking and you can also use it with the american made BNF planes as they all use that protocol... you CAN even put both the modules in and swap between them with a 2P2T switch.

Before you start, you must find 3 connections inside your radio: Vcc, GND and PPM. The Vcc is generally any 5V or there abouts (the modules permit a margin) point from the radio. The GND is easy as this you can even get straight from the battery negative connection if you wish. The hard one would be the PPM signal, which if the radio has 2 boards, one as transmitter and one encoder, then it's "the third wire" that connects these. If it's all on one board, then you're going to have to dig around for info on the net and see if anyone has isolated the signal carrier with an osciloscope. One question that might help, although being 27mhz I doubt it... does the radio have a trainer port of any sort? What make and model is the radio?
 

highflying

Senior Member
The radio is an unknown model of a company called Heng Long. Here are the TX and RX: Heng Long2.jpg
Heng Long1.jpeg

They both use balance connectors to plug in, and both use crystals. This, as I say, was a tank radio, so it has functions for firing and moving the turret. There is NO trainer port, and it is a cheap radio, so I was just hoping.
 

Epitaph

Ebil Filleh Pega-Bat ^.^
Mentor
Ufff... I don't think you'll have much luck finding the PPM on that unless you look yourself, and you'll need an osciloscope for that. Why do you want to convert it to 2.4? I'm imagining a tight budget for a new radio...
 

Epitaph

Ebil Filleh Pega-Bat ^.^
Mentor
For what you're going to pay for an internal module you can get a cheap 2.4ghz radio from HK to start with... or if it's also the delivery issue as that can work out expensive on some articles, maybe look into getting a second hand one fron there in the UK. Have a look on UK forums as you might find something on their buy/sell section, or on ebay too. Don't get caught up in 2.4ghz, as the 35 band is also a good one (I think that's the legal one in UK same as here), and exclusive to aeromodelling. The problem with the 27 band is everyone is on there because of it being the CB radio one. You can probably get a nice 35mhz radio really cheap because people suffer a false sence of fear from them (people flying years with them with no problems at all, then comes 2.4ghz and all of a sudden they're scared... why?) And sell them cheap. If it's something like a Futaba or a Sanwa (which seem to be selling a lot second hand) or a Multiplex, something like that, you can probably upgrade it later on to 2.4 no problem, and maybe get the computer radio for something like £30... which is what a module would cost you.

I think you're going to have to go in steps, but spending money to put that radio to 2.4 isn't worth t, there are better alternatives. If I see something good and cheap up there in the UK I'll let you know
 

Epitaph

Ebil Filleh Pega-Bat ^.^
Mentor
Another thing... how are you at woodwork, and how many channels can you get away with? What is it you want to fly?
 

highflying

Senior Member
Mainly motor gliders to begin with, but I want to move onto tri's and I was going to buy a 3D 4 channel. And yeah, my woodworking is OK, why?
 

Epitaph

Ebil Filleh Pega-Bat ^.^
Mentor
If it were pure gliders wouldn't be so much a problem, but motorgliders is a little harder. I was wondering about it fot you to make a transmitter out of a second hand car one. No matter

Here's an example, but there are better offers out there

http://www.preloved.co.uk/adverts/show/110012968/futaba-skysport-4-and-reciever-combo.html

This is a basic 4ch radio made by Futaba, althou it can be upgraded to 5ch. It will also take a 2.4ghz module as there are people that have upgraded it... in fact, I think someome's even gotten it to 7 channels. But not being a computer radio there are no trim memories, all very oldschool. No mxixes, expos or anthing like that. It does have a trainer port so it is compatible with some flight simulators.

But as I said, there are better offers out there if you look.
 

Epitaph

Ebil Filleh Pega-Bat ^.^
Mentor
This one is not a standard UK frequency, but it's not a bad radio... it's easily upgradable to 2.4ghz with an internal module...

http://www.ebay.co.uk/itm/TRANSMITTER-41-MHZ-/111362810554?pt=UK_ToysGames_RadioControlled_JN&hash=item19edbda2ba

I have this same transmitter in 35mhz and works well. It doesn't say if it comes with a receiverand I doubt you'll find one over there of that frequency, but if you're gouing to upgrade to 2.4, then it's not a problem, and for £10 with free delivery, not bad base at all... but hurry, times running out on it!

It's 4 channel, upgradable to 5ch, with channel reverse, 4 model memory, trim memory, delta and V-tail mixes, expo, EPA... has a trainer port on the back with the standard Futaba square plug for using with flight sims, and this is where you wire in the 2.4 system.
 

highflying

Senior Member
Thanks so much. This obviously took some time to do, so thank you. I will look into the links and ideas you put forward. Thanks, again.