homemade V4....

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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rich080487
Posts: 5
Joined: Thu Jun 09, 2011 10:47 pm
Location: Bristol, UK

homemade V4....

Post by rich080487 »

I know the DIY assembly kits have not been available for a few years, due to the complexity of the SM components etc.

I was wondering has anybody attempted/succeeded in making their own V4 unit from the base components? Maybe using vero board with point to point wiring (not tidy but functional)?

If I try to go this route does anybody have a complete list of required components and potential uk suppliers?
Also, are there any parts that I can only acquire from Brent? i.e pre-programmed components?
I have searched the forum, but all the topics are very old, so I wanted to ask again because I guess things have changed.

I know I could buy a ecu, but surely half the fun and sense of acheivement is making it yourself!

Any help appreciated,
Rich

brentp
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Post by brentp »

Hi Rich,

All the information in the downloads section (schematics, firmware, etc) should enable you to build your own controller. To program your processor you will need a dedicated HC08 programming hardware. Use this to first program bootloader, then use the bootloader to load the Megajolt firmware.
Brent Picasso
CEO and Founder, Autosport Labs
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rich080487
Posts: 5
Joined: Thu Jun 09, 2011 10:47 pm
Location: Bristol, UK

homemade V4....

Post by rich080487 »

Brent, thanks for the quick reply.

I have few questions before I start to buy bits!

1) The V3 parts list states the resistors and capacitors as 0.25W 5%. Am I ok to assume the same for the components listed on the V4 schematic?

2) On V3 you used a DB9 instead of the RJ11, I was thinking of using this to reduce the amount of wires needed?
Why did you change to RJ11, were there problems with the DB9 connection? (I am also open to suggestions for removing the need for a usb-serial cable, without buying a new laptop)

3) Out of the 3 ICs, the only one that needs programming is the MC908QB8? Do you still have any of these left that you could sell + ship to me with the bootloader and/or mj firmware already installed? Cost?

4) Could you tell me any technical info to source the Schottky diodes? Voltage? Power?

5) Is there any difference between an axial and radial capacitor? Does it matter which I source?

6) Will max232a i have chosen work?
http://search.digikey.com/scripts/DkSea ... 232ACPZ-ND

7) Is the oscillator I have sourced suitable?
http://search.digikey.com/scripts/DkSea ... ds=X947-ND

8) Does it matter what type of LED do I use? 5V? 12V? Power?

Really sorry for all the questions, but I just want to make sure before I commit to ordering all the parts.

Thanks in advance,
Rich

brentp
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Post by brentp »

Hi Rich,

yes, those parts should work.

Unfortunately, we don't have any V3 processors available.
Brent Picasso
CEO and Founder, Autosport Labs
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rich080487
Posts: 5
Joined: Thu Jun 09, 2011 10:47 pm
Location: Bristol, UK

Post by rich080487 »

brentp wrote:Hi Rich,

yes, those parts should work.

Unfortunately, we don't have any V3 processors available.
I am building a V4, so was wondering if you had any V4 processors left?

I am also still unsure what technical specs the Schottky diodes should have?

Thanks again,

Rich

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