Cooperative build?

[gn0stik]

Thanks for the invite folks. I know some people are working in sub-teams. I think this is an efficient use of time, and a good way to create synergy. "Two-heads" and all that. At any rate, I'm getting ready to start hunting down parts. Cores tomorrow etc, home depot parts next, wire after that. I was wondering if there's anyone here in the seattle-ish area (pierce, king, kitsap counties, WA) that would like to form a sort of sub-team and work cooperatively say, one night a week.

Or alternatively if there's anyone working alone at the moment, I can buy the cores and wire and start working on that, and build two, since there's a two core min anyway, and someone else build two drivers?

I'm trying to get caught up as fast as possible, so something like this will help get up to speed quicker.

My lab is starting to come together in a corner of my garage at the moment, which I don't really like because of the moisture, but it's the only place I have at the moment so it'll have to do.

Glad to be on board.
Rich.

[gn0stik]

The responses I have been getting are not exactly what I was talking about. After re-reading my post, I can see how I might have been a little vague. I'm looking for someone in my area that I might actually be able to rub elbows with a little, and form a local brain trust. Although I'm willing to work with anyone over the internet, some face time can be infinitely valuable. With the exception of one possiblity (who hasn't responded yet to my question of whether he's local or not), everyone responding has been in another state. Don't get me wrong, I will be perfectly happy to work over the internet or phone, I can use all the help I can get. But I'm kinda looking to put something together similar to what the California group has going.

Ward, if you are local, I'm in. Just need to figure out the logistics. Where, when, blah, blah.

Tao, if ward is not local, since you responded first, we can go in on some cores together.

I think I'll be going the AD9959 route unless someone has a good reason I should not. Perhaps I should wait until Bob's hexcontroller is released?. The AD9959 test board is Spendy, but time is money, and time with my family is priceless. And it's a flexible, and very configurable solution. If anyone has any thoughts (good or bad) about that, please let me know, I want to make an informed purchase.

Regards all,
Rich

[MarkSnoswell]

Hi,
   I bought in the AD9959 development board -- as you say, time is money and what you get on this board is good value. Having said that I haven't run it up yet ... I have been doing a lot of testing and simulating of ouput drivers and mosfet drivers... I want to get that side of things working well and safely so I dont blow my development board one I do hook it up.

The one thing the 9959 wont do is pulse width -- you can cheat it by pairing channels and using phase offset to get two pairs of pulse width controlled channels... bu tnot three.

I just finished some good simulations tonight -- it turns out that the simplest way to power the coils is with a single low side mosfet and use the pulse width to deliver just enough energy so that the BEMF is ecactly what you want -- this is the mose efficent use of power and the simplest configuration -- so pulse width control is critical.

I'll post circuits and summaries somewhere here in the next few days.

mark.