Quote from: MarkSnoswell on July 27, 2007, 02:30:36 AM
There is no ideal, of the shelf,  controller out there for what we want.

I would beg to differ!   Look into Xilinx's FPGAs here: http://www.digilentinc.com
These things are basically high-speed reconfigurable logic.

Specifically, there is a small Spartan 3 board for $99 that should do everything we need it to do--I have been using this board for the past year and have been very happy with it.  As I posted on my thread, I can release the source for a basic three-phase 100KHz+ pulse generator, with full computer control of all parameters.

Eldarion

hellooooo! all

good to be here  and BIG thanks for setting up this forum

looking forward  to getting  some good info

has any one found a source  for 16ga solid silver coated wire yet?


wer

Quote from: wcernuska on July 27, 2007, 12:53:33 PM
@Bob,   What minimum PWM time increment do you achieve, while I am still considering 200MHz and down adjustable GAL clock logic design, where target DDS frequency dictates actual minimum PWM time increment?  Thanks.  Just in case my idea has some merit.  Nodern PLD's run much faster, but they are not familiar to me yet. 

Ward  I hope I have not posted twice... dohhhh!

I really don't care as much for PWMs as I do just using those ports as straight logic level outputs. This way I can set my pulse width referenced to time rather than a percentage of the cycle time (frequency). What you will need for pulse on time will directly depend on how much latency is in your output processing, drivers, and switching devices.

Just about any microprocessor/microcontroller device can be adapted for use, if the clock speed is fast enough. For basic power system functionality, it doesn't require a huge amount of processing time. If you wish to get into the more wild aspects, then processing speed will become very important.

Bob

Quote from: weri812 on July 27, 2007, 02:22:12 PM
hellooooo! all

good to be here  and BIG thanks for setting up this forum

looking forward  to getting  some good info

has any one found a source  for 16ga solid silver coated wire yet?


wer

I sourced most of my 16 guage, 20 guage, and 22 guage, from a surplus outlet in Florida by the name of SkyCraft Surplus. They had many types and sizes of mil-spec wire in stock when I last checked. You might have to call and ask them what they have in partial spools, as they usually only list full spools on their web site. If I remember right, they were about 10% to 20% the price per foot of buying new wire. I use 20 guage magnet wire on the longitudinal winding(s).

Bob

Edit: Here is a picture of the first longitudinal winding, since I removed this picture from the other thread.

@Bob,
Good job we have you on our team. Look forward to seeing your circuit and coil setup.

@Wer,
PTFE coated silver plated copper wires are available here:
http://www.wires.co.uk/acatalog/cu_sp_ptfe.html
0.25mm, 0.4mm, 0.6mm and 0.9mm - expensive, around 21GBP for 100m of 0.6mm

I have ordered all of my wire to date from this company, and they are very good.

@Mark,
AD9959, 4 channel DDS, looks ideal although it is very expensive, around 49 GBP in the UK.
Saying that, the option to request 2 samples is available.
I requested 2 samples of a less expensive DDS chip a while ago and they turned up about 5 days later - brilliant!

As I understand it, you should be able to link many (less expensive) DDS chips to the same oscillator and use the reset to sync them.

@Eldarion,
I remember you from the EnergyMover on google - MEG project.
Can you get fine frequency increments using your  spartan 3 board, say 0.1Hz?

@All,
I have the cases for my DDS 20 boards and I plan to drill holes/cutouts to mount the boards into the ali cases.
I want to test sine wave to duty cycle idea first using a high speed comparator.
With luck I can get down to less than 1% duty.
May need to look at some other ideas to get a fixed narrow pulse in the 10ns range.

After watching the video about:
Tesla transverse and longitudinal electric waves
http://video.google.com/videoplay?docid=-721789270445596549&total=32&start=0&num=10&so=0&type=search&plindex=0
I was thinking, where did the three control coils idea come from and the three layers of coils?
When SM cut the core open the cross section was all foam, I think, I could be mistaken.
So that means all the coils were in the thin outer layers.
If we can get the compass needle to spin, using just two frequencies, we must be on the right track.

Regards
Rob