Model Boat Mayhem

Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: Gopher on August 04, 2013, 11:17:13 am

Title: What is this
Post by: Gopher on August 04, 2013, 11:17:13 am
Hello everybody, anyone an idea as to what this is? I know it's fairly old and think it's from Action there are 2 red, 2 black wires and the lead for the receiver but as to what it's for not got a clue, also can you mix and match receivers on one of my tugs I am using a Tamco 2.4 tx and rx the other is on the 27 can I buy any 2.4 receiver or do I have to get another Tamco.
Title: Re: What is this
Post by: inertia on August 04, 2013, 11:36:26 am
This does look like one of Craig's old switch units, but I have no other information on it. Ref your radio, 2.4GHz radios in general tend not to work with other brands so I'd go for another Tamco receiver; much less hassle that way.
DM
Title: Re: What is this
Post by: malcolmfrary on August 04, 2013, 01:52:47 pm
The IC is a "dual D type flip-flop".  It has a lot of odd uses, but I suspect that in this case it is being used to check pulse length as to whether it is longer or shorter than what it is looking for.  The BUZ71 is a power transistor, good for more volts than we are usually interested in, and, given enough heat sinking, quite a lot of amps.  Given the lack of a heat sink, I would guess at a 1 amp switcher.
The variable resistor (grey box, bottom left) probably sets the switching point.
Title: Re: What is this
Post by: More Coffee on August 05, 2013, 12:42:54 am
I'll go so far as to say its a relay driver.
Shot in the dark..more reliable than a timer and op-amp
 
Title: Re: What is this
Post by: inertia on August 05, 2013, 08:12:53 am
I'll go so far as to say its a relay driver.
Shot in the dark..more reliable than a timer and op-amp
Having run the business of ACTion Electronics for six years after he died, I'm pretty familiar with Craig Talbot's designs and the way he thought. I think Malcolm's analysis is spot on. If this had been intended to drive a relay then there would have been one on the PCB, and he wouldn't have used such a high-spec transistor just to power a coil.
Dave Milbourn
Title: Re: What is this
Post by: Snowwolflair on August 05, 2013, 08:33:30 am
Electric flight motor switch I think.
Title: Re: What is this
Post by: More Coffee on August 05, 2013, 03:50:23 pm
Like I said ..it was a shot in the dark.
The the high spec transistor would increased the duty cycle..again like I said a shot in the dark.
Title: Re: What is this
Post by: inertia on August 05, 2013, 04:11:38 pm
No offence intended, old thing; I was more musing about my old mentor and his work than admonishing you. It was almost certainly a light-load circuit switch for a small model boat or truck - those being the type of models he was most interested in. I've seem similar (but not identical) ones which he made for other folk.
DM