MegaJolt on a flapper EFI

ChrisJC · Post by **ChrisJC** » Fri May 31, 2013 4:42 pm

DaveEFI wrote:This is the circuit from the MS Extra site:-

That is a bit more like it (base resistor), and a max voltage of 160V. I might still consider a zener diode or something to catch a spike that would destroy the transistor.

Also, why a relay coil? Why not just an inductor?

Chris.

DaveEFI · Post by **DaveEFI** » Fri May 31, 2013 5:45 pm

It's a DIY answer - most will have a relay lying around. Quite easy to remove the coil from one too.

FWIW I had one using a 2N2222 working for a few weeks. A base resistor will depend on what's driving it - driven from an EDIS8 tach output, you don't.

daxtojeiro · Post by **daxtojeiro** » Fri May 31, 2013 6:58 pm

kiwicar wrote:Hi
I ordered 50X2n5551s off ebay wednesday night, 100X1k resistors and 5X 100 uH chokes to make up this adaptor, then I bought a ready done adaptor off Phil yesterday to save me a lot of grief. . . If any one wants resistors or 2n5551s let me know and you can 2 of the trannys and 4 resistors for 60p the chokes will be £3 each, I only have 5, (I have no real idea if they are the right size, I guessed! but I think they should work) all including postage. If you buy the choke I will throw in 2 trannys and 4 resistors for free (they should all be here in about a week)
personally I think the best plan is to buy a ready made one off Phil!
Best regards
Mike

Hi Mike,
throw the transistors away. We bought several different transistors from EBay, as the price is increadable.
But a lot of them failed, so I ended up throwing them away. Shame as they were cheap, not that Farnell is expensive, but stick with the main component suppliers if you want to buy the bits,
Phil

ChrisJC · Post by **ChrisJC** » Sat Jun 01, 2013 7:21 am

daxtojeiro wrote:
kiwicar wrote:Hi
I ordered 50X2n5551s off ebay wednesday night, 100X1k resistors and 5X 100 uH chokes to make up this adaptor, then I bought a ready done adaptor off Phil yesterday to save me a lot of grief. . . If any one wants resistors or 2n5551s let me know and you can 2 of the trannys and 4 resistors for 60p the chokes will be £3 each, I only have 5, (I have no real idea if they are the right size, I guessed! but I think they should work) all including postage. If you buy the choke I will throw in 2 trannys and 4 resistors for free (they should all be here in about a week)
personally I think the best plan is to buy a ready made one off Phil!
Best regards
Mike
Hi Mike,
throw the transistors away. We bought several different transistors from EBay, as the price is increadable.
But a lot of them failed, so I ended up throwing them away. Shame as they were cheap, not that Farnell is expensive, but stick with the main component suppliers if you want to buy the bits,
Phil

Agreed. Those transistors are made by many different manufacturers. Some are good, some are cheap Chinese copies, and don't meet their spec.

Chris.

kiwicar · Post by **kiwicar** » Mon Jun 03, 2013 10:42 am

Hi
I now have one of Phil's boxes and as no one is interested in the transistors they will go in the colection of elecrical bits in the garage!
Best regards
Mike