Synrad / Laakman 10W CO2 Laser...

[300EVIL]

Okay..... GOOD NEWS! I figured out What I was doing wrong. After looking at the "whole" RF driver board I noticed the 12V/5V computer type connector. Well, It turns out that 5V connection is needed!

I am now getting the RF driver board to create RF! However, new problem.....

When I turn on the FET power ( 30V @ Limited to 8A) The SMALL coil above the FET starts to heat up and smoke! (from the coating) I only had the circuit powered for 10 seconds or less and the FET PS says it's drawing around 2 amps. The laser does not appear to have any output either.

Any Suggestions?

Thanks!
Adam

[300EVIL]

The ceramic cap looks like it's touching the coil but it's not. It's actually about 1/8" away.

[300EVIL]

IT WORKS!

After taking Chris's suggestion of crushing the coil a little tighter, I got the tube to light! Makes Swiss cheese out of cardboard too! My whole lab stinks now.

Anyway, I measured the output. From a cold start, I get about 3.5W this slowly slopes down to around 2W after about 30 seconds of continuous output. I'm currently feeding the FET with 35V @ 10A but the FET only draws 2A of that.

Any chance I can get more power out of this little sucker? I tried further tweaking of both the large and small coils on the head. I just seem to loose power not gain any. The large coil could probably be crushed closer but not by much. The small coil is basically completely crushed.

Any suggestions would be greatly appreciated!

I'll post some pics of it running tonight. Maybe some video too.

[heruursciences]

If it lights you have the circuit in resonance, but for fine tuning, You may be able to adjust the ferrite tuning slug in your pre amp board in the can on the OUTPUT SIDE of the board.

2A seems very low as for draw, you should draw between 6 to 7A. Also, removing the solder furrle from the source connection of the output amplifier ARF transistor, notching the board and replacing with 10 gauge bare copper wire soldered to the transistor lead and to the tube input will GREATLY increase your RF delivered to the tube.

[300EVIL]

If it lights you have the circuit in resonance, but for fine tuning, You may be able to adjust the ferrite tuning slug in your pre amp board in the can on the OUTPUT SIDE of the board.

2A seems very low as for draw, you should draw between 6 to 7A. Also, removing the solder furrle from the source connection of the output amplifier ARF transistor, notching the board and replacing with 10 gauge bare copper wire soldered to the transistor lead and to the tube input will GREATLY increase your RF delivered to the tube.

So, your saying, get rid of the BNC connectors and eliminate the output pin on the FET and replace it with solid copper wire?

[heruursciences]

Get rid of the tube side BNC, keep the bard side BNC, remove the output POST from the ARF transistor board and wire a thicker copper wire directly to the output LEAD of the FET to the tube.

[300EVIL]

Here's some running video for ya'll!

http://www.youtube.com/watch?v=deSGne6oKPE

[Hemlock Mike]

Wait 'till you put a ZnSe lens in front of that Hope you can get your drive current up. I have the single unit driver and getting about 10 amps at 30 volts. Be careful of your Scientech sensor up there.

Mike

[300EVIL]

Wait 'till you put a ZnSe lens in front of that Hope you can get your drive current up. I have the single unit driver and getting about 10 amps at 30 volts. Be careful of your Scientech sensor up there.

Mike

Hey Mike,
Yeah, I have a big GaAs lense here. I'll try focusing tonight. Hopefully I can figure out how to get more power out of it. Should be easier now that I have it running.

The Scientech head is good for around 20W so I don't think I'll kill it from the static beam.
Thanks!
Adam

[GooeyGus]

Hey Adam, Just curious, what model sensor head does your scientech meter use? I'm trying to figure out what kind of power my sensor head can handle. The meter goes up to 100W, but I think my sensor would melt at 100W