Variable Digital power supply wanted !!!!{NEEDED}

Xenodius.....if you, or anyone you know EVER are able to get your hands on a decent (preferrably digital) variable voltage and current regulated power supply, PLEASE keep me in the loop ! I am gonna split this reply off of the main topic, so others will see it, any maybe someone has a used one, sitting around gathering dust that they would want to give me since I am such a dang nice person !!! LOL ROFL !!!! But seriously - any and all hints, or ideas on how to get one fairly inexpensive, or better yet, FREE would be appreciated - I have needed one for such a long time, but always had other priorities that prevented me from obtaining one. I saw one on Ebay - a dual output up to 3 Amps, and 12 volts (I think) for close to $100 shipped.

Re: Variable Digital power supply wanted !!!!{NEED

SenKat... the electronics store here sells these exact power supplies for $100 + tax.

http://www.mpja.com/prodinfo.asp?number=14602+PS

I am using one and it seems to be pretty decent given the price. It's got some weight to it, and I can ship it out to you if you'd like... It has 2 modes of operation (Current Control and Voltage Control) and it is very well regulated overall... My only complaint is the Fine-tune knob only does one turn, so to turn up the voltage or current, you have to get close enough with the coarse control and then fine-tune it as much as the fine-tune knob lets you. It also is very effective to use a DMM right after the output to get a better picture of what the current out of like.

Hope this helps;
DDL

Re: Variable Digital power supply wanted !!!!{NEED

Ya - It isn't in my budget at teh moment for certain - but I will definitely keep that in mind I was hoping for a pity-power supply ! LOL (kidding) like if someone had two, and only wanted/needed one...etc...that kinda deal

Re: Variable Digital power supply wanted !!!!{NEED

OH... hehe

--DDL

Re: Variable Digital power supply wanted !!!!{NEED

lol Okay, I will keep it in mind! The one I got has +-1.5 volt and +-1 amp adjustments for each rail. If I can get my hands on another, its likely to be an Acopian commercial grade PSU of unknown range. What range are you looking at? It was quite a surprise my dad came across this one, but you never know if he could nab another!! The outputs on these things are EXTREMELY stable!!

As far as how to get one cheaply... I really dunno, I would watch eBay like a hawk. My dad has got a lot of things from places that are upgrading. Some examples, I am not kidding here: 17 office printers, 6 nice computer chairs, 2 desks, 11 old PC's, 3 laptops, about 80' worth of PC power cables, a ton of assorted monitors, a recovery system for semi trucks that have tipped over, a 40 gig tape drive, one enormous, ancient CRT monitor that weighs exactly 47 pounds, 21" screen, 1600x1200 resolution, unbelievably crisp, 80Hz refresh rate, ~12 grand at time of purchase! That beast is about 14 years old now and my dad is STILL using it LOL!!! He wants to get an LCD sometime but is waiting for the good quality ones to go down to a reasonable price. 400 bucks just isn't worth the desk space! So most of the stuff he gets is office related, but some is just plain random. He was offered a full 250 gallon drum of 98% sulfuric acid once... I am so sad he turned it down, that would have made 1,000's of pounds of high explosives LOL!!!

But yeah, the PSU I got weighs about 10-12 pounds, its hefty for its size! The only thing I would keep in mind is shipping! Though I think it would fit into a Priority Flat Rate box, one of those $7.50 ones...

Re: Variable Digital power supply wanted !!!!{NEED

I am making one, check here for how to:
http://www.redcircuits.com/Page36.htm
Looks pretty simple, don't know how stable it will be though :-?
It won't cost much at all, and it might be quite 'fun' to make.
I can buy digital panel mount lcd volt meters from some shop thing for like R40 ($6), so I would use that to measure the current and voltage.
Jonno

Re: Variable Digital power supply wanted !!!!{NEED

What I'm doing is plug in a DC voltage input, removing need for transformer and rectifying diodes. Powering it by +12v and -12v from PC power supply that I've got giving constant voltage at the moment.
The total cost, excluding transformer, diodes and multimeter is around R80 ($11). So it's pretty cheap. Looking at another $12 for meters, so about $25 to make this. Don't know how much cheaper Radio Shack will be, but this is a good option. You can't get a constant current mode though. But you can limit it, according to the voltage.
Would this still be useful for working with laser diodes?
Thanks
Jonno

Re: Variable Digital power supply wanted !!!!{NEED

You have some very interesting ideas! I'm intrigued and would very much be interested in the outcome of this design

GL;
DDL

Re: Variable Digital power supply wanted !!!!{NEED

Well, thank you Daedal...
You can see it takes in the transformer neutral and live, joins it together and runs it through some rectifying so, from after D1, it's a DC voltage. So supply it with DC voltage direct to those points and ... voila, you have it. It can't do Constant Current/ Voltage mode, but still, it's cheap.
Jonno