• If you like antique engines, vintage tractors or old iron, please register and join us. When registering, please provide your CITY and STATE in your location!

Electronic Buzz Coil

DustyBar

Subscriber
Last Subscription Date
01/03/2019
I found this circuit in a 20 year old, out of print, Strictly Internal Combustion magazine. I have not built it yet but if I understand what I'm reading sparks start 2 msec after the points or wiper makes contact and then continues for 5 msec. Slight timing adjustment will need to be made for the 2 msec delay. The 5 msec duration should save the battery if the engine stops with the points or hall sensor closed. With points A and B terminals are used. With hall sensor A, B and C terminals are used. I believe it works with most any standard ignition coil. There were corrections made to this circuit in two following issues and I've shown the circuit with the latest changes.
 

Attachments

David Cave

Subscriber
Last Subscription Date
07/19/2019
This post got me thinking again. Last year I designed (lots of trial and error) and built a buzz coil based on a modern car coil - the type of coil where one sits on each cylinder of the car engine and are computer driven. The beauty of these coils is that they have internally your transistor Q2,3,4 and part of the 555 timer. As I remember my version used a coil, 2 resistors and 2 capacitors. If I can find the schematic I'll post it.
 

DustyBar

Subscriber
Last Subscription Date
01/03/2019
...buzz coil based on a modern car coil - the type of coil where one sits on each cylinder of the car engine and are computer driven. The beauty of these coils is that they have internally your transistor Q2,3,4 and part of the 555 timer...
Please do post the circuit. What engine had the coil on plug you used?
 

David Cave

Subscriber
Last Subscription Date
07/19/2019
I didn't build it for a specific engine although I did run it on a 3 HP John Deere battery/sparkplug engine. I was talking to Mr. John Deere, Jim White, one day and he threw out a challenge - could a buzz coil be built from a modern GM coil with the built in electronics. Got one working, put it in a buzz coil sized box and sent it to Jim. Now the embarrassing part, I can't find the schematic. Next time I talk to Jim, I'll ask if I sent him one. Basically I used a low valued resistor, 10 ohm maybe, in series with the module. The coil trigger lead had a RC network to delay the coil trigger. When the engine points close my module got 12V immediately thru 10 ohms, then the trigger voltage came up (thru the RC delay) and fired the coil. When the coil fired the 12V collapses due to the 10 ohms. When 12V falls it resets the trigger which shuts off the coil, the 12V rises and it repeats.
 
Top