I would like to DIY a meter

[keeperx]

I would like a power meter, i want to make something like the laserbee, is this something i could make myself?

[FourDee]

Yes you could, but the problem would be calibration ...

[keeperx]

well i can cross that bridge when i come to it.
something cheap but slightly intelligent is all i need.
no need for hard core accuracy, just something pretty damn close
also should be like up to 0-2 watts or even 0-1 watt

[daedal]

well i can cross that bridge when i come to it.
something cheap but slightly intelligent is all i need.
no need for hard core accuracy, just something pretty damn close
also should be like up to 0-2 watts or even 0-1 watt

I can send you a DIY detector with the calibration reading as compared to my meters... You can just connect it to a DMM and do the divide-by factor manually. That's the cheapest way

Send me a PM if you're interested

--DDL

[mixedgas]

well i can cross that bridge when i come to it.
something cheap but slightly intelligent is all i need.
no need for hard core accuracy, just something pretty damn close
also should be like up to 0-2 watts or even 0-1 watt

The question becomes what do you want on the low range. Because at some point you need to decide if you want silicon or thermal. Without some careful engineering thermal is tricky below say 30 mW. And silicon starts needing calibrated, removable attenuators over 100 mW. Attenuators are a cast iron witch to make at home. BOTH is not a easy answer. You can order ND filters from Edmunds and use them for attenuators, but the cost starts to approach ebay prices for a whole meter.

In your case the only easy cal is finding another LPM owner with a widely adjustable laser, you need 0-x watts in 1-2-5 steps, ie 10, 20,50 mW, then 100,200,500 mW and so forth. Usually I can find such lasers at SELEM and I will have my good coherent with me.

I'd highly advise just getting a Lasersbee or a powerpen or coherent 200 or 210, 210, and just getting it over with. Or a used thermal puck on ebay.

If you happy with a relative reading just to track your own lasers, other means can be arranged.

The 200 series thermal circuit is in documents on the FTP server. I placed it there a month or so ago. Do note that it uses 1% precision parts.

If you can find the right green led, this works for home use but not for trade, and only for green

http://www.sbk-laser.ch/PowerMeter.htm, again it takes the "right" green led. Upside is it costs maybe 99 cents to 1.50 and shipping. Downside, maybe 5% accuracy and a two hundred mW limit at best.

I'd go with daedal's offer, its a lotta work to cal a PM.

Steve

[Laserman532]

dang keeperex, your time must be worth zero. laserbee is the bang for the buck. Daedel sounds like a good solution, Keeperex, why dont you see if you can do a trade with jerry if you dont have the bucks right now. But that is like saying does anybody know the formula to make rubber, my left front tire is out on my yugo.

[lasersbee]

Hey keeperx...

If you can get a coherent Thermopile Head.. they are calibrated at 1uv/mW..
then all you would only need is a DMM that can read in uV... or design a precision
linear amplifier to increase the gain to a more usable level...
The Kenometer uses such a Coherent head and amplifier and outputs it
on a 200mV DPM...


Jerry

[trwalters001]

You're best bet is going to be the Laserbee.
You can't beat it for the price.
I own one and it's tits on Ritz (good cracker!)


Tim

[lasersbee]

You're best bet is going to be the Laserbee.
You can't beat it for the price.
I own one and it's tits on Ritz (good cracker!)


Tim

ROFL....... First time I hear that expression.... tits on Ritz...
You're cracking me up....

Jerry

[Laserman532]

speaking of Tits on a Ritz

Here is a picture of Michael Jackson with tits I engraved on a gram cracker...

I just thought I would toss that out there to keep with the theme!