Model Boat Mayhem

Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: essex2visuvesi on August 14, 2014, 10:05:49 pm

Title: ESC repairs
Post by: essex2visuvesi on August 14, 2014, 10:05:49 pm
My son managed to wire the battery round the wrong way on our Vintage 1:24 Tamtech, and now the CPR (Combined 27mz RX & brushed ESC) is dead :(
Does anyone know of anyone who could repair this, as finding a replacement is a difficult (and expensive) option
Title: Re: ESC repairs
Post by: HMS Invisible on August 14, 2014, 11:12:27 pm
Does anyone know of anyone who could repair this, as finding a replacement is a difficult (and expensive) option

 Could or should ?   %)

Just look out for the frequent forum posters on the subject of rc electronic repairs. They should.

Keep track then ask one of them how many freebie repair jobs on transmitters, receivers, sail-winch servos, escs  and you'll find out if they could.
Title: Re: ESC repairs
Post by: essex2visuvesi on August 15, 2014, 06:42:00 am
Fair point....


I have had someone recommended on another forum, which I'm looking into, but it's always good to have options
Title: Re: ESC repairs
Post by: Subculture on August 15, 2014, 07:06:58 am
I have one of these units, and it went pop on me, so I had a poke around inside.

In my case, the ESC lost reverse, so I suspected the output transistors. These turned out to be fairly modest BJT's, not even mosfets, with no heatsinking so probably unsurprising I smoked them (running 2s lipo).

I'm not a collector or purist, so elected to exchange the electronics for something a little more current. I used a miniature 4-channel orange receiver and Thor 15 ESC with a servo amplifier from a mechanically knackered servo to replace the onboard unit. It all that fits easily within the footprint of the old CPR unit, and the original servo is retained (it's a bit of odd shape as I'm sure you know).

Result is a much nicer car to drive, smooth throttle, more power to the motor and the benefits of 2.4ghz R/C.
Title: Re: ESC repairs
Post by: essex2visuvesi on August 15, 2014, 08:17:39 am
I had already looked into this and I have a combo 2.4Ghz rx/Esc from a 1:18 RC car that would do the job..... This is fine in the short term however, the car is intended to be a resto job so keeping the original parts would be preferable.
Title: Re: ESC repairs
Post by: Subculture on August 15, 2014, 08:32:15 am
You can get the newer electronics into the original CPR unit box, so it looks stock, you would need a mock-up large aerial and crystal to complete the illusion.

What I can say about the original board, is that it is all SMD (apart from the BJT's) and the components used will be probably be difficult to find as they're all obsolete- so it's going to be a case of searching on ebay. Probably easier to look for a good used working unit.
Title: Re: ESC repairs
Post by: hmsantrim on August 15, 2014, 12:47:10 pm
Hi e2v.
 when you mentioned CPR unit (Cardiopulmonary resuscitation) I thought your model  needed the crash trolley... {-)
 
  Frank