Hey Rob,

Sounds great! I'll be very glad to see how the output waveforms look, especially at high frequencies.

By the way, I'm stuck on the last couple of parts for my control circuit. Here's are links to the posts I made below. They concern the voltage detection circuit and the HV biasing circuit:

http://www.physicsforums.com/showthread.php?t=191440
http://www.physicsforums.com/showthread.php?t=191045

God Bless,
Jason O

Hi Rob,

You're right about that. Thankfully, I did figure out how to do both the HV throttling circuit and the voltage measurement circuit. The only reason that I'm even bothering with this is to give the controller the capability to run autonomously to self-regulate the coil; particularly in the event that we can't directly control it while the coil is running. Plus, the measurement capability will help us to do other experiments like frequency and bias sweeps to help tune the coils and automatically find the sweet spots.

But I can say that the design I ended up with the the voltage measurement circuit is greatly simplified now. I'm not concerned about measuring the current and the power but only the voltage. (plus we can calculate the current and power knowing the load on the coil anyway). The simple idea is to just go with a resistor divider with a cap in parallel to help smooth out some of the hash (and short out any RE that might work into the circuit). Then I'll just use an ADC to sample the voltage and send it to the microcontroller.

As for the biasing circuit, I'm keeping that simple too. I decided to go with the Op-amp that I mentioned in the post. After talking to the tech support people at Linear, they confirmed that the op-amp I spaced out would work fine to directly throttle the HV supply IC. Now I'm going to be working on drawing the circuit schematics to tie everything together.

Finally starting to see the light at the end of the tunnel .

God Bless,
Jason O

Photo showing DC socket in place.
Also have the LED on/off rocker switch in now, just the BNC sockets to go.

(http://i100.photobucket.com/albums/m25/kingrs/DDS20_case_DC_socket.jpg)

Hi Bruce,
It's not brilliant,some of the holes were out by about 1mm, I cut the window for the LCD larger than needed because I took a chunk out when the router was slowing down and decided to cut I nice curve into the side. Should have held it firm until the router had stopped.  (mental note: get workshop assistant).
The rocker switch is very large for the case size and I will mount the next one on the side next to the DC socket.
I scratched the anodized case a few times during drilling - swarf under the workpiece. I got around this after the event by covering it with pvc tape.
The good news is the 3mm foam stuck on the inside pushes the LCD module onto the board and clears up the missing segment problem.

@Ward,
Its taken a few hours to make this one, but it is a prototype and I am getting some special milling drills for cutting the larger holes in the case.
The routing of the LCD window took about 10 minutes, so I am pleased with that. The next one will be a bit neater.
BNC sockets;
1. Square wave
2. Sine wave
3. Programmable pulse width square wave

I have not built the circuit for the last output yet, but this will be to drive the DS1023-100 chip using a PIC to give a pulse from 3ns to about 255ns(I think) in 1ns steps.

Also I will be doing some artwork to print onto tech sheet via laser printer and glue to the case to provide legends for the controls.
I have 4 cases to drill/mill and mark up for you.
I will be leaving the black trim off because it fouls the screws, but more important it is too close the sine wave amplitude control.

Regards
Rob King