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Old 12-11-2008, 02:04 AM   #101
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Everything has been priority mailed as of yesterday so it should be there by the weekend. Unfortunately work, school, and this really got the best of me for about a week. My appologies.
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Old 12-14-2008, 09:59 PM   #102
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Received yesterday - thanks!
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Old 12-16-2008, 01:45 AM   #103
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Great, letme know how the install goes!
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Old 12-16-2008, 03:49 AM   #104
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Sweet, it arrived, probably a few days ago. I was expecting it to arrive UPS but it was in my mailbox in an envelope. Much smaller than I expected.

Installing it today.
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Old 12-16-2008, 11:00 AM   #105
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Sorry for the anti-climatic end They are pretty tiny, I remember thinking that myself when I deboxed the boards.
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Old 02-05-2013, 05:54 PM   #106
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I know this thread is old, but are dwell reducers still being sold?

thanks

Last edited by dafastone; 02-05-2013 at 08:30 PM.
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Old 02-06-2013, 12:20 AM   #107
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I thought some guy made some on m.net?
If not I may work on a new design.
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Old 02-06-2013, 12:46 AM   #108
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Quote:
Originally Posted by JasonC SBB View Post
I thought some guy made some on m.net?
If not I may work on a new design.
I have been looking and have not found much success in finding someone selling them. But if your making some Im interest. please let me know. also are you in the bay area? I think i can recall you being in san jose.
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Old 02-08-2013, 04:34 PM   #109
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If nobody's doing it I will re-start my project.

I'm in SJ and your car could be the test bed.
What year ECU do you have?
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Old 02-08-2013, 05:13 PM   #110
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I have the stock 94 ecu
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Old 02-14-2013, 03:29 PM   #111
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Please let me know if you will be making any more dwell reducers, I would like to use Trackspeed engineerings cop kit but need the dwell reducer.
Thank you very much, George
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Old 02-14-2013, 03:29 PM   #112
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I have a stock 2000, thanks
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Old 02-19-2013, 05:46 AM   #113
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Jason, I had a place build a batch of them but they didn't work as expected. One of the guys doing the testing reported back with this:

Quote:
An Electronic Engineer friend (who now wants me to "look" at his rear suspension) has helped me find the problem an a fix.

The board works fine when only one channel is opperating but not when both channels are opperated simultaneously. The problem is the reference voltage to the opp. amps is not stable and gets worse when both channels opperate, to the point where the "tipping" voltage is not reached.

The quick fix is to solder a 47uf capacitor across R6. This stabilises the reference voltage and allows both channels to work simultaneously. However, as the frequency (engine speed) increases, the "averaged" reference voltage will increase and the delay time (dwell reduction) increases. On my board, the delay time varried from 1 to 1.2 ms over the expected engine speed range (it was 1.6ms when only one channel was opperated).

A better fix would be to replace R5 and R6 with 1k ohm resistors and add the capacitor across R6. This will reduce the influence of the opp. amps input impedance and reduce the change in dwell time with frequency.

A possible even better fix would be to replace R6 with a Zina diode as well as the above, but you may need to change the R/C circuits to return to the desired delay time, depending on the voltage drop of the diode.

Bottom line, you will need to change the boards to make them work.
I tested them on the bench using a PIC, but only ever tested one channel at a time:

Testing rig:



Testing 'A' part of board:



If you get a chance I'd love to hear your feedback!

I ordered from an earlier BOM but had a later revision of your PCB layout file, hence the jumpers. Does the later revision incorporate the above fixes?

Cheers
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GB Fully Assembled Miata Dwell Reducer Boards-7168950377_a5e060ea81_z.jpg   GB Fully Assembled Miata Dwell Reducer Boards-7168947593_8c3900ae63_z.jpg  
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Old 02-19-2013, 09:33 AM   #114
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Guy on M.net took our money and sold us dwell reducers that didn't work and he didn't stand by his work! Mikerx or something like that? All I know is he fucked me!
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Old 02-19-2013, 11:28 AM   #115
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Amellrots is your PCB the same as the above? If so could you mail me yours?

Last edited by JasonC SBB; 02-19-2013 at 11:49 AM.
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Old 02-19-2013, 11:30 AM   #116
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Yes, can you fix it maybe? Please PM me your address and phone number and I will get it shipped out to you!
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Old 02-27-2013, 08:47 AM   #117
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Want me to send you one of mine too Jason? Mine is a completely different build to the miata.net GB.
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Old 02-27-2013, 04:54 PM   #118
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Where did you get it? Whose PCB layout is it?
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