I know most RTR radios aren’t that good, but this one is definitely the screwiest I've had. The failsafe works well if the Tx is turned off, but causes glitches galore with weak signal strength. Get the buggy far enough away, and the engine rpm rises all by itself in little bursts of speed. Sometimes the steering glitches also.

Although a new radio is on my list (I just haven’t picked one yet), I have been annoyed at the glitching that is occurring. It didn’t used to do this, but has been getting progressively worse. I see others have this problem with the stock RTR radio as well, and I seem to have come up with a cure for both range and glitches. I’ll address the range problem last, as it may not be easy for anyone to do as you need some test equipment, however the glitching is easy and I’ll show you that mod first.

GLITCHING:

After significantly maximizing my radio range, I still find I have glitches. After a bit of experimentation, it turns out to be interference from the ignition. So it turns out spark EMI is the trouble, and it’s coming from the ignition wire. In order to reduce this, all that is needed is to shield the ignition wire from the ignition coil to the end of the sparkplug boot. I used nickel plated copper braid for this. I also used a bit of heatshrink around the end of the boot to keep the braid from fraying. In addition, I soldered on a ground wire to the braid and grounded it to the engine using a ring-lug (solder type). I did split the existing grommet so that it would be easier to get over the braid, but it’s possible you might not have to do that. See the picture below for the set-up. Samples of the material I used are on the roof. The spark-plug cover that fastens to the roll-cage has been removed for clarity.



I strongly suspect that this problem becomes more significant as the sparkplug ages, but I didn’t have a spare to try to see if replacement would help at all. Besides, I don’t want to prematurely change sparkplugs just to keep the glitching down. This shielding method seems to work perfectly fine.

Another possible cause of glitching is metal-to-metal contact. I've read that some of you use fuel line on the throttle linkage to eliminate the metal-to-metal contact there. I used heat-shrink as I was afraid fuel tubing could cause binding. Anyway, the ignition seems to be the real problem, but as this is easy to do, I went ahead and did it as well.


RANGE:

There's a lot more RF output power available from the TF-10. It appears the factory de-tunes the transmitter for lower output power. Not sure why, perhaps a legal reason.

Transmitter:

If you know an electronic technician who has access to an oscilloscope, or better yet, a spectrum analyzer, it's easy to adjust. You have to retune L4 (the second last coil from the antenna....L4 is marked on the PCB). It won't hurt to tweak L5 as well, but it seemed fine on mine. (You should have the antenna connected and extended for tuning, especially when adjusting L5). Don't mess with anything else on the PCB, or you might wind up detuning the PA and then you will have a scrap radio (fried RF output transistor). Oh....he will have to de-solder the three wires from the steering pot to get the PCB turned over for adjustment. They can be re-soldered after the adjustment (white, red, black....in that order from the left). He has to be careful he doesn't bridge the wire mounting pads with solder. (Re-assembly note: Make sure the throttle trigger adjustment is all the way back and the rear screw put in the innermost hole to the Tx center)

Receiver:

Matching the receiver is always the best move, but as this is FM, you can tune the Rcvr input coil over quite a range with no apparent effect. You might as well leave it alone.

By the way....crappy Rcvr design....if you turn it on without the Tx on, the failsafe lights, but the servos have no holding power. The Tx has to be on at some point after the Rcvr is turned on, if the failsafe is to work when needed.

FINAL NOTE:

So after you do this, you can still get glitches, but the 5B should be a long, long ways away when that happens. In case of emergency, shut off TX, and the failsafe will lock everything down without any more glitches.

The fact is, I can now operate the 5B at well over 100 yards away, with the antenna down (just to test things) and not have a signal glitch or failsafe shut-down. Maybe farther, but that’s as far as I tested it.

Now I can research a better radio at my leisure, plus save up in the old piggy-bank for it. Hope this may be of help to some of you.

nice post

HPI RADIO =

nice. even after i sold my rtr radio. i still have range issues with a spektrum, maybe im just in the bermuda triangle.

thats an awsome right up.. ive been having the same problem. itr was fine when it was new. but now its not so sweet. ive posted many questions about this on diffrent forums, but all i got was that hpi radios suck.. wich is not what i wanted to hear.. i recantly heard that someone did this on a boat motor. could you please tell me where you got that "wrap"stuff. it looks like somekind of cloth. how were you able to solder that. im not too fond of the look, but if it helps, im all aboard. im not going to do this mod untill next week, but i will post up to conferm that it works.. thanx and give me some info on that wrap stuff\, like were i can get it

you can just use some electrical wire and coil it around the lead if you cant find the braided stuff.... car performance shops usualy have the braided wire.....

also you can use a resister spark plug (if they dont already have them?)

nice info there Argess well done

Ryan

Classic !

Any AM radio will get twitchy at times with the baja, because the engine size has an effect on RF interferrence, more so than the smaller nitro engines that have alot less problems on AM, just get an FM radio set and be done with any problems , period !

i got my braided wire from the plumbing section of the hardware store , and good tip about the ground wire to the engine and spark plug never thought about doing that , i braided my ignition lead mainly for looks , and maybe your post would have been helpfull to me BEFORE i went and bought a spektrum DX3R lol, With the stock radio i was getting no more than 3 meters in radio range , it was really terrible .

I'm not sure where I got the braid, but it was tinned-copper and used for shielding of electrical cables. It was nice as it can expand and contract quite a bit, so it can just slide over the spark-plug boot, and then be stretched out to be smaller where it covers the ignition wire.

In retrospect, I could have soldered the ground wire to the braid under the flywheel cover and grounded it to one of the ignition coil bolts.

In lieu of soldering (especially if you wind up with stainless steel braid), you can put a slit up the braid for a few inches and twist it into a pigtail, then crimp a lug to it and ground under one of the ignition coil bolts.

One thing more I should do is wrap the exposed braid with a bit of tape or something as it may rub along the roll-bar, and I don't want the rollbar to chafe through.

For anyone wanting to do a quick test, just wrap the exposed ignition wire with aluminum foil. Keep wrapping all the way past the spark-plug boot and crumple it around the sparkplug base. Won't last, doesn't look good, but it will give you an idea if the final version is worth doing for you.

I run the DX3 with a failsafe on the third channel, and I get ZERO problems. I honestly can say I've never had a glitch or loss of control in any ares where I've had my car, truck, or even my electrics 10/th scales with the Spektrum system. Perhaps its indeed some other RF interferences that are causing issues.

Between Nomadio and DX, I'd say it is a MUST HAVE upgrade IMHO aswell as Outerwears and a failsafe on all large scalers from the get-go.

Most of the problems are caused by the ignition system, with a little bit caused by throttle linkages.. I gave up on the stock FM radio soon after I got the baja because of small problems and I just didn't trust my investment to a cheap radio.. I got the React and it works great.. same would go for the spektrum... I can't say the radio is total junk however.. I use it now in my brushless Rustler and Brushless motorcycle.. just nothing with ignition system.. Range on mine is fine, never had issues with that at all..

I have the B5 SS kit so of course I had to supply the radio. I allready have a Spektrum DX2 so I added another receiver to it for the Baja B5. Anyway it works perfectly, great range and no glitches.

is there ever going to be a day that the old spektrum to the new spektrum DX3R going to get interferance one day ?