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FrozenGate by Avery

PLUG & PLAY CO2 BURNING LASERS only $150 DELIVERED

Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

Tottish  I set my power supply to 32 volts and this thing is drawing a whopping 13.42 amps, and  at 28volts it draws 12.22 amps this doesn't seem right you would think lower voltage would mean Higher amprage anyway it's drawing higher amps than I thought it would... my power supply is Lambda varible rated 28 volts 12 amps but the plywood is still flaming up at7ft in four seconds thats enough to burn your butt ;D Lynn Its probably my radio shack meter the reading just doesn't jive :-/
 





Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

that little anp puts out 220 watts I was thing it was around 60 or 70 with the amp draw :)
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

DArn -- with the gels topped off, I'm getting 14 Amps with a DC Amp Clamp meter and now hitting 230 Watts RF output.

That's why you don't touch the antenna on the tube.  :D


I have a 28V 17 Amp Power supply coming.  I'm not sure now that a single string of 18650's can supply the power without too much I^2R internal loss.  

Mike
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

Oh, man. thats alot of power.... Hmmm, Iwonder if I could possibly order another one and put them in parallell... I'll talk to the distributer. I want this little monster to have as much power as it wants!

Oh! The PCB's are done and so is the sourcecode-programing and the hardware programming also. I will mount them tonight and post a picture.
I will make them a "bare" PWM-module so that you guys could fit it with any LC-filter you find suiting, ie the one Chris suggested at page 11 (or so). I guess the optimal filter can vary a little from laser-module to laser-module and installation to installation so I've decided to leave thet one open. At least for this first batch.
For example, I think I will try to shield off the giant RF-emitter that is our laser (if you guys don't think it will actually damage it) and then I might find another more suiting filter (if I will even need one) on for my installment because of diffrent RF-properties in hte proximity of the module. I don't know about you guys but I don't feel right having an RF-emitter this big completely unshielded.

Chris:
I was thinking that I would send all the modules to you for you to distribute to the others participating in this groupbuy that are interested in a module (spikec and nightstick is already down for one each). Does that sound OK for you? I think this solution would be better so I don't have to send so many parcels overseas.
How many modules would you need? I have materials for 10 modules so I was thinking about sending you 8 of those for a first batch. If we find improvements to be made we could include it in a later version. How does that sound to you?


/Tottish
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

tottish just a heads up at 27 mhz your rf siginal isnt harmful really nothing to worry about higher freq, above 440mhz then you want to get further away from the antenna correct me if im wrong anybody but thats what Ive learned 27mhz isnt as harmful as higher freqs :P
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

Thanks, but I wasn't really worried about my health but "nearby" electronic equipment. Maybe I'm just paranoid but I think it would feel good with some shielding. But this wouldn't damage my Laser, right? Just, at worse, momentarily knock down performance a few notches. Right?

What about the PWMs? Is it OK for you to distribute them on the continent?

/Tottish

EDIT:
Oh! and thanks for the amp-readings guys! New PS ordered! :D
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

Tottish if the reflected power is high it can be hard on the power transistors in the Amp that I dont know if it would be bad enough to do permenant damage especially if you keep burn times down to keep things coool :) I dont have a jumper to hook up a swr meter between the amp and the laser I think Mike has a  watt/power meter ready to test maybe if he has some fariday cageing  he could test with to see how it affects the reflected power. would that help? otherwise I will make up a cable and try :)     Mike did you use 7 18650's  and I was wondering about how many times you were able to fire that laser up Im thinking maybe 5or6  ten second burns?  :)
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

I don't have my 18650's yet... I plan to use 8 in series -- that's ~ 32 volts no load. Losses at 10 amps will drop that but I don't know if the cells can output 10 to 14 amps. With PWM, set to half power, they might work good.
I have to instsll my ferrite prayer blocks tonight on the PWM. The new variable power supply I got goes nuts in the rf field. Also, the 80 watt reflected power I'm reading is part of the heat / current problem. Now lets see --- dip the plate - peak the antenna !!! For all the old hams who actually tuned a transmitter ;D

Mike
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

Well, I tore apart the 2 laptop battery's, they contain sony 18650gr cells! cool! 8 in each one, they are kinda low, I don't know how safe recharging these will be, they are at 2.5 and 2.4 volts per cell. The packs test meter didn't show any bars. Ive got one on my bench supply with the current set at 100ma, and the no load voltage set to 16v. Ive been watching the individual cells really close, they are all still room temp, and up to about 3.7v per cell now after about 3 hours.
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

Those cells must be in series/parallel for 16 volts to charge them. Good idea to limit the current to only 100 ma until you know their condition.

I found 6 volt 4 AH gells for ~$8 each. 5 of those might make a go too.

Mike
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

Yep, 2p4s... they're rated 14.8 per pack.... At this rate, it will be charged in 18hours! lol :D

I thought about 5 x 6v gell cells, too big. bulky! but if these 18650's arent good, thats the next choice.
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

Mike says: "The new variable power supply I got goes nuts in the rf field"
Thats exactly the kind of thing I was worried about. I look forward to the measurements with shielding guys. Unfortunatly it will be a while before I can fire up my own piece since the new requirements on the PS will extend the deliverytime a few weeks.  :'(

Hehe, another thing I forgot to tell you guys was that my mouse for the PC also went nuts in proximity of the laser. Had to unplug the mouse and plug it in again for it to work.  ;D

NightStick:
Sorry for not answering your latest PM but I have alot to do right now. I will reply when I get word back from Chris. (EDIT: about the proposed distrubution-method, that is.) ;)

/Tottish
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

When my 28 volt power supply arrives, I plan to add bypassing and ferrite cores to protect. If the SWR (reflected power) can be lowered, some of these problems will be reduced.
The 6vX4AH cells aren't too big -- heavy though >: :(

Mike
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

ya, by the time you get 5 of them, it'll be pretty large! :o 24 nimh d-cells would be smaller and more ah. So much for making it small. Well, the cells have gotten up to 3.85v per cell, and the current has slightly dropped by 10ma, I hope these are gonna work, I'm kinda nervous with them. If I use all the cells, in pairs of 2 to increase the current, there will be 16 cells in this thing... If one of them turns loose and blows up, the rest are likely to follow, I wouldn't want to be holding this thing if it blows up! :o

added:
3 of these would do it. :)

http://www.onlybatterypacks.com/showitem.asp?ItemID=10715.5
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

16 cells WOW --- Should be OK for short burns.

My little bastard just took the coating out of my thermal power head >:(

I gotta get the PWM quiet. The scope still shows noise real bad.

Mike
 
Re: GB ROUND 2 OPEN for 10W RF EXCITED CO2 LASERS!

hi guys I just finished my box its 4" x 6" x 2feet long with the power supply mounted on the rear my power supply was going nuts also meaning I couldnt get a steady voltage reading THE GOOD NEWS I trimed my box all the corners in 1/2" by1/2" aluminum angle (corner stock) I went to measure voltage and it showed 30 volts smooth as silk  Im guessing my frame work is containing the RF  I ran the laser for a minute straight and with my forced air cooling it didnt get very hot at all I gona try to put some pics on tonight :D I also tried 7 18650's and they were lighting up the plywood :o
 
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