Diodes D3 and D4

Megajolt Kit assembly Question and Answers. Be sure to review the <a href="http://www.autosportlabs.net/MJLJ_V4_kit_assembly_guide">Kit assembly guide</a>

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Xyclone
Posts: 2
Joined: Thu Sep 02, 2010 3:34 pm

Diodes D3 and D4

Post by Xyclone »

All right so I feel like a bit of a maroon, but here it is. Assembled my V4 Megajolt last night and in assembling the power supply portion first, made sure all diode stripes were accounted for and were identified, but in my haste (rather stupidly) put both D2 and D3 in the same orientation instead of the correct opposite. So subsiquently D3 was not orientented right, so in the first power test, little blue smoke from either D3 or D4. Now after reversing it, no more smoke and all voltage checks were fine. I'm assumign this is just a portion of the regulation circuit? I'm aassumign I fried one or both D3 and D4, so what does this affect? I will replace them as soon as I can, but jsut want to see if I can go on testing things.

NITROPIXIE
Posts: 704
Joined: Sun Sep 07, 2008 1:54 pm
Location: Fareham, GB

Post by NITROPIXIE »

Hi Xyclone and welcome to the forum. What car are you jolting out of interest??

The diode you have fried will have been D3 and no there wont be anything else that would have damaged by putting this component the wrong way round except maybe the track on the circuit board.

As you said, diodes D3 and D4 are part of the voltage regulation circuit and you will still have normal operation of the board/circuit without this part. If you use it on a running car there is a possibility of added noise from the alternator, etc which may cause problems, but the noise reducing capabilities of the rest of the circuit may well be over engineered to reduce noise anyway and you may not have any problems at all). Using it with a stabilised power supply (e.g. 9v battery), then there will be no problems what so ever.

Hope this helps some

Ryan
1310 A-series Mini, lightened and built myself. V4 board and loving it

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Xyclone
Posts: 2
Joined: Thu Sep 02, 2010 3:34 pm

Post by Xyclone »

Thanks Ryan, after looking at the schematic, I had figured as much, but wasn't 100%, thanks for the confirmation (I'm a degree'd computer/electronics engineer, but haven't gotten to play with electronics in quite some time, so rather embarrassing to even have to ask for help with a simple regulation circuit, but it is what it is right? lol).

Currently my MJ setup will be test benched on a stocker A/C 1600cc vw motor. Once fully tested, it may very well go on one of my personal vehicles, but I have an engine customer who may be interested in it, so I figured I would try it out and if it works I may build one for myself. Just completed a 1914cc for him, have another 2054cc stroker on the bench, and just started as of last night a stock displacement high reliability oriented engine with quite a few lubrication system mods and such for a vw bus.

Thanks for the welcome

Pete

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