ESC or radio problem - Reverse is flaky

[Coelacanth]

I got the electronics working in the Marui Galaxy I'm working on. Programmed the ESC (one from a re-re Tamiya Grasshopper) and it programmed successfully. Neutral and full forward work fine, but I'm having a strange issue with full reverse.

When I immediately push the trigger for full reverse, or even hold it there (assuming there's a delay for brake)--nothing happens. But, if I move the trigger only partially, and THEN full, it will do partial & full reverse. It's as if it doesn't recognize or allow full reverse, it requires partial reverse first. This seemed to happen with 2 different transmitters (using the same crystal frequency, but I can't imagine this be due to the crystals).

Any ideas, anyone experience this before?

EDIT: I should also mention it did the same behavior with different motors.

[drbelleville]

Have you tried it with another radio? You can also contact Tamiya Support USA via their site, and they may be able to lend more insight.

Regards
Maurice

[Coelacanth]

I tried with 2 different transmitters. An old Attack 2-stick and a Magnum Sport (T2PH). The radios both otherwise seem to function perfectly. And reverse works fine too, as long as I don't immediately go full reverse; if I push the trigger/stick half-way, it'll reverse immediately, and then I can go full reverse. It just won't let me do reverse at all if I push the trigger/stick immediately all the way.

I'm thinking it's ESC-related and may have something to do with the brake delay function not working properly...

[Coelacanth]

Hmm I just found something researching this issue on the 'net, I'll have to test this. My assumption would seem to support this.

It seems that pressing the trigger full reverse activates the brake. You then need to let the trigger return to neutral, and then (supposedly) full reverse can be applied.

I never tried exactly that, I'll do it this weekend. If anyone can confirm this is how their Tamiya re-re ESCs work, that would be great.

[dg98adams]

Duh moment... that's exactly how the radio works in the used Stampede I bought. it's a 27 Mhz that comes with the RTR version.


Now I want to charge a battery and see if that's it. Thanks.

[Coelacanth]

Duh moment... that's exactly how the radio works in the used Stampede I bought. it's a 27 Mhz that comes with the RTR version.


Now I want to charge a battery and see if that's it. Thanks.

Hopefully that's what it is...haven't been home yet to double-check and confirm. Tonight probably.

[Coelacanth]

Confirmed! It turns out the ESC is working just as it should. It's funny that none of the other ESCs I've used work that way; they brake when you hit full reverse for a period of time that you specify, then go into reverse...none of this "reverse once for brake, reverse again for reverse" stuff.

I'm also intrigued why giving it partial reverse will make it reverse all the time--even if I'm at full acceleration then go into half-reverse. That can't be good for the motor or car...