Analyzing and Hacking a Power Supply Board

RE: Analyzing and Hacking a Power Supply Board

e14 Contributor — Wed, 08 Jun 2016 19:34:13 GMT

Great Article,

Impressed with your ability to rewire and reuse old technology. I am wondering though how long the solenoid or relay will last. It looks rather old and may be hard to find a replacement when it fails. Got me thinking that you could add a battery operated circuit to count the # of times the relay is turned on. Then may let you know if it will fail soon. A simple counter chip to output to a battery operated microcontroller could read the status. Would it be a good idea to use a Normally Open switch between ground and relay enable pin? Then when you test devices you can shut off the supply easily while you make changes to circuits that it powers.

RE: Analyzing and Hacking a Power Supply Board

the-dubster — Tue, 07 Jun 2016 19:15:16 GMT

Ooh, just remembered, in the UK there was a Electronic Salvage company who used to advertise in the electronics mags - Bull Electrical!

They used to sell boxes of random stuff for not a lot, yes, I bought some.

Look up the 'Rabbit' (telecomms) phone tech - I had a wall mounted base station / repeater from a defunct technology! Not everything you got was particularly useful! [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-53cec2b0-f0b8-4786-9315-c97c8db2aa59/0825.contentimage_5F00_938.png:16:16]

RE: Analyzing and Hacking a Power Supply Board

the-dubster — Tue, 07 Jun 2016 19:08:25 GMT

Ah the memories you have brought back for me! My father also heavily influenced my life in similar ways, a large difference though is that he tried turning his hand to everything; rather good with his hands and all that. I suppose it was because we had no money to speak of that he tried to do everything himself. Cars, building, DIY and all that, you know, the usual stuff. It definitely rubbed off on me - can't remember the last time someone else fixed my car/house electrics/Oil boiler/roof!

Electronics though came from another source - well two to be precise. One was my Uncle, I'm not entirely sure what his job was, only that he worked for Barratt Homes and had something to do with the electrical installations for those homes. He could have just been a sparky I guess, just a white-collar one. Dunno, never asked. The other source of my passion was a neighbour (not that sort of passion, not that sort of neighbour), he gave me my first breadboard (a step up from the 1001 electronic whatsits kit, you know, the ones with spring contacts) and a bunch of random components. Thus a new hobby was born!

Onto the relevance to this post, old bits you can get for free!! Ah the joys of getting given random PCBs to gut / hack (it wasn't a phrase back then). The fun (and burned fingers) from de-soldering all the bits (that you may or may not ever use), searching and researching data sheets to figure out what that component was/did. I probably still have loads of that stuff somewhere.

I still do it today - the salvaging bits thing, even though I kinda (sadly) left electronics behind years ago - I did the analogue (discrete) circuits, moved to TTL & CMOS and then (briefly) dipped my toe into PIC Microcontrollers (ok, I bought one once)! Then I stopped! But the hoarding and hacking didn't.

LED dashboard / instrument lamps - what, pay £££ for those! I can make them for pence! A 12V 6W LED spot fitting for £3 - ooh, a really bright torch for . . . . . . .yup, £3!

Maybe it's a hangover from my youth, maybe my old man made me want to do things myself, maybe I'm just tight! Dunno, but I salute you for reusing, recycling, reappropriating discarded bits! A nice project and a nice power supply.

RE: Analyzing and Hacking a Power Supply Board

Workshopshed — Tue, 31 May 2016 20:22:16 GMT

Nice project, good job John

RE: Analyzing and Hacking a Power Supply Board

jw0752 — Thu, 19 May 2016 06:28:34 GMT

A separate blog post has me playing with the camera and trying to improve my pictures. I was particularly unhappy with my picture in this post where the Displays of the little voltmeters were hard to read. I have determined that I will need better control of my lighting as the camera doesn't quite have the capability to cover the full range of conditions with my present fixed intensity lights. Here is a replacement picture taken at an exposure of 1 second.[View:/resized-image/__size/620x465/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-53cec2b0-f0b8-4786-9315-c97c8db2aa59/5633.contentimage_5F00_181394.jpg:620:465]

John

RE: Analyzing and Hacking a Power Supply Board

dougw — Wed, 18 May 2016 02:31:15 GMT

First your Dad enables your hacker spirit (thanks Dad) but now its your son feeding you all this material (thanks Mike)

Networking and connections start with the family - it pays to have a good one.

Linear power - it has been a while since I had the luxury ... nice work.

RE: Analyzing and Hacking a Power Supply Board

Jan Cumps — Tue, 17 May 2016 20:08:03 GMT

Thanks Dad!

This made my day. Month. Year. [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-53cec2b0-f0b8-4786-9315-c97c8db2aa59/contentimage_5F00_11380.png:16:16][View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-53cec2b0-f0b8-4786-9315-c97c8db2aa59/contentimage_5F00_11380.png:16:16]

RE: Analyzing and Hacking a Power Supply Board

DAB — Tue, 17 May 2016 18:40:37 GMT

Hi John,

Nice hack job. It looks like you started with a high quality power supply, so you now have a decent power source.

I like the idea of nail polish to coat cut traces.

Did you have any problems with the cut traces along your cut line?

I was concerned that there might be an edge where live voltage could short out along the edge.

Great job.

DAB

RE: Analyzing and Hacking a Power Supply Board

mcb1 — Tue, 17 May 2016 07:41:26 GMT

Nice work.

I do like the warnings as the 1/2A Slow Blow fuse will be at 120v AC (I suspect) and easily contacted by accident.

Mark