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ArcticMyst Security by Avery

RF excited CO2 lasers

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Dave -- you old fart  ;D    You remember !!!!!!

I was going to try making an odd wood stock for it but it's hard to get a good view.

Mike
 





daguin

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Leave me alone!

I'm remembering teen-aged fantasies [smiley=evil.gif]

I was 14 when it came out ;)

Peace,
dave
 
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Dave --

I have the video tape.  Watched it last night to see the gun --- Really !!!
Funny spoof on SiFi flicks even back then.
I found a picture of the grip/stock. It's a bit wierd --- even for me :D

Mike
 

daguin

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Hemlock Mike said:
Dave --
[highlight]I have the video tape.  [/highlight]Watched it last night to see the gun --- Really !!!
Funny spoof on SiFi flicks even back then.
I found a picture of the grip/stock.  It's a bit wierd --- even for me  :D
Mike


Careful there . . . .Someone will get you a walker. ;D ;D ;D ;D ;D

I haven't seen the movie in a very long time. I saw a DVD the other day on a $9 rack somewhere. I should have picked it up then. Now you've got me thinking about it, Imma haft find it again.

Peace,
dave
 
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The TTL frequency is ~ 24 kHz.  Power is controlled by PWM.  You vary the pulse width ratio.

Mike
 
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Hot then but ................................... NO

That's Jane Fonda :mad: Bad news in the viet Nam War era. Bad press.

Mike
 
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I've heard that name before, doesn't really have any meaning to me though.
That must have been an older movie...
 
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The movie was made in ~ 1968............   NEVER mention her name again.

Back to topic ---- you can build a PWM using a 555 timer chip or get one from Chris at Herurr......

Mike
 
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Yeah I will probably be getting one from Chris in the coming weeks and then just glue it into the maximum power output setting. But first I have to sort out a power supply issue. My six laptop power adapter idea isn't working quite as planned, the supplies each run at slightly different voltages and so one of them takes on the entire load and overloads, shuts off, the next one takes over and overloads, and shuts off about the same time the first comes back on. And during this time the higher voltage supply is trying to force current backwards through the weaker ones and its causing a whole whack of weird clicking noises and the laser only gets 3-4 amps max.

So I've ordered some high power diodes to keep the supplies from backfeeding each other and some power resistors to limit the current from each supply.

THEN I can wire up some control electronics and, if all goes well, I can use my time off during march break to build an enclosure and put it all together.
 
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EH --

If you are going to glue the PWM to full power, you don't need a PWM. That's what makes it adjustable on power. If you only want power MAX, just feed the TTL input 5 volts DC - that's all.

Mike
 
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No I meant I'd glue it at the 90% max setting which is supposedly the most efficient setting with the highest output power. I'll rent a 20 watt power meter from school and set the laser to the sweet spot and glue the pwm there.
 
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I seem to have run into a problem. I connected power today and the laser started up, ran for about a second, and then the output died. A closer inspection shows that now when power is supplied to the RF board and the PWM, only the "MOD OK" light comes on and not the "RF OK" light. The power transistor doesn't even get warm at all. And no signal is sent to the laser. Furthermore it is not the fault of the laser because it still happens when the laser is not connected, even though it worked fine before. Finally it is only drawing ~50 mA from the 12v supply when before it would draw over 1.5 amps.

any ideas what the problem might be?
 
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EH -- My drivers are not like yours but running one without a load reflects the power as SWR and can blow the big transistors. Ask NightStick -- He's found out a couple times. Radio frequency circuits are VERY different from the old DC circuits of the red pointer crowd. Do you have high frequency test equipment?

Mike
 
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Hemlock Mike said:
The movie was made in ~ 1968............ NEVER mention her name again.

Jesus was made in ~0. NEVER mention his name again. ;)
 




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