Desktop power supply - 1502 x 1703 well known clone - schematic

[pickit2]

I picked up a scrap power supply, from a local repair shop, it looked in good condition except for a cracked lcd display & the voltage pot.
Original reason was for parts, when on the work bench it was working, but a few components need to be replaced, to bring it into use as a stand alone unit again.
So parts on order and while waiting thought not a bad project, someone might make use of the information.
I looked for the schematic and only found the main part, so I added were the meters connect, some components are not the same, but should be easy to sort.

[Wizpic]

Here is another one with meter's and indication of CV or CC mode 0-18V 0-2amps , I think there pretty much the same other than the way they drive the power transistor,
Was thinking of changing the pots and making it digital control and replacing the meter with better one's but already have a couple of them

[pickit2]

While waiting for a replacement LCD I have been running it with a external meter, when I need to measure current.
It was the current display that was damaged, I set the current max with a 10k pot also as a temp fix.
and moved the 6k8 pot to set the voltage.

It is a very steady output with no more ripple than my THANDAR PL310 another bin find

I have a few 12-0-12 Toroidal transformer and going to make a 0-25V @ 2.5Amp dual Supply, with or without the Meters.
I'm adding a stop/start switch quick off/slow start, or variable, so I can set the voltage & current and leave it set.

[sadman]

some more design

[bobcat1]

Hi
Most power supply schematic published here are of linear type (but one)
The future is in switching type or combined (linear + switch) preferred a one controlled by a microcontroller
I would like to see more schematic of lab PSU with switching control - I think we ca learn a lot from them

Bobi

[Wizpic]

Have you seen this one from here, very well designed and everything is there to build one, Some of the parts are costly but the guy who designed it wanted quality. Keep considering to bite the bullet and build one
http://www.ianjohnston.com/index.php?option=com_content&view=article&id=92:powersupply&catid=3:hobbies&Itemid=8

[sadman]

Hi
Most power supply schematic published here are of linear type (but one)
The future is in switching type or combined (linear + switch) preferred a one controlled by a microcontroller
I would like to see more schematic of lab PSU with switching control - I think we ca learn a lot from them

Bobi

you can go here
http://vrtp.ru/index.php?showtopic=23867&st=0#

[Gallymimu]

I actually started a design for a ATX based benchtop supply kit of sorts.  Put a SEPIC converter on one channel and a boost converter on the other for -30 to 30 on one channel and 0 to 30 on the other channel at 3A to 5A each followed by linear stages to reduce ripple.  I figured leveraging the volume of the off line portion and UL listing would make sense (and it was the only way I could see to keep the cost any where near reasonable in small volumes).

That said I'll probably never get it finished

[Checksum8]

Here's is another clone variation HY1803D

[pickit2]

I never followed my own advice only bought one lcd glass panel, and not 2, now I have a working Power Supply with one back lit display and one refective.
not worth fixing to make the both the same.

But it's all working as expected, voltage pot needed a 6k8 but used a 10K pot & 20K resistor to make up the value.