Power supply K-3206

[mgf897]

Does anyone have a copy of the schematics for a K-3206 40V/3A power supply?

I recently bought one used of eBay and would like to check it over. I believe the power supply was originally sold as a kit. Thanks.

[tautech]

Brand?
Photo, as it might be a re-brand. 

[mgf897]

Hi Tautech, it's a dick Smith model. I'll post a picture when I get home.

[aargee]

It was an Electronics Australia design (Dec '93 / Jan '94). Silicon Chip magazine will have back issue copies.

[Tac Eht Xilef]

K3206.zip. Enjoy 

I think it includes the very important errata about the transformer secondary connections - the original overlay / connection diagram had, IIRC, the CT & one side reversed. (From memory it took 12 months or more for EA to post that errata!)

As a general tip: it also benefits from added decoupling, etc. otherwise it's a bit prone to ring/oscillate. I've got a link or list somewhere somewhere which mentions a few mods; I'll try and dig it up post it later.

edit: Thinking back on it, the original overlay / diagram might've had one half of the secondary shorted to the CT/gnd (the schematic was correct). No errata mentioned in my PDF, so you'll have to trace it out yourself (it's pretty obvious). Needless to say, don't power it up without checking that out .

Also, the DSE kit supplied a slightly under-spec'd E-core transformer rather than the specified toroid - end result was it had trouble reaching 40v or, if it could, it couldn't supply much current.

And here's the thread on EDAboard where they discuss anti-oscillation fixes/mods.

[mgf897]

Awesome, thanks tac eth xilef

[Webserfer]

I know this is over 4 months later but I just got lucky on ebay and got a brand new unopened kit for the power supply if you still need any docs that may of came with it. Was fun to unbox I'll say

[VK5RC]

Now that little puppy served me well for probably the best part of two decades as a quick little power supply, still have it. The only issue I had was it does over heat a bit if you start pushing it on a hot day (and its thermal cut out I set a bit low) and its start up voltage curves aren't fantastic but a great little unit for starters.
The usability of analogue type PSUs are pretty good.