Meanwell PSU in a model B

for bbc micro/electron hardware, peripherals & programming issues (NOT emulators!)
Post Reply
dominicbeesley
Posts: 549
Joined: Tue Apr 30, 2013 11:16 am
Contact:

Meanwell PSU in a model B

Post by dominicbeesley » Tue Jun 12, 2018 4:30 pm

Does anyone know of a source of brackets for fitting a Meanwell PSU into a model B PSU carcass?

I got all the bits to put one into my Master but the Rifa's have popped (with only a modest amount of smoke) in my model B this afternoon and I'd like to fit the PSU to the model B as that is the one that does all the heavy lifting.

If not I'll start whittling some out of scrap tonight...

D

User avatar
hoglet
Posts: 7113
Joined: Sat Oct 13, 2012 6:21 pm
Location: Bristol
Contact:

Re: Meanwell PSU in a model B

Post by hoglet » Tue Jun 12, 2018 6:24 pm

Edit: Sorry, I realize now you are asking about the Model B. I'll leave this info up anyway.

Storrtech sells the Master ones on eBay:
https://www.ebay.co.uk/itm/BBC-Master-M ... 3040838591

They are Simon's open source design, from this thread:
viewtopic.php?f=3&t=13006


Dave

dominicbeesley
Posts: 549
Joined: Tue Apr 30, 2013 11:16 am
Contact:

Re: Meanwell PSU in a model B

Post by dominicbeesley » Tue Jun 12, 2018 6:59 pm

Yes, thanks, they're the ones I've already got. I've whittled something imperfect from a couple of off-cuts for now.

User avatar
daveejhitchins
Posts: 4139
Joined: Wed Jun 13, 2012 5:23 pm
Location: Newton Aycliffe, County Durham
Contact:

Re: Meanwell PSU in a model B

Post by daveejhitchins » Thu Jun 14, 2018 6:21 am

It might be worth asking Mark, at RetroClinic, if he could do some kits for this 'upgrade'. I, or anyone else, could supply the brackets - I'll drop him a line. If he doesn't think it's worthwhile, I'll ask him if he could supply all the cables etc. and I'll hold a few kits.

Dave H :D
Parts: UM6502CE, GAL22V10D, GAL16V8D, AS6C62256A, TC514400AZ, WD1772, R6522, TMS27C512, AT28C256
Products: ARA II, ABR, ATI, AP6, MGC, AP5 . . .
For a price list, contact me at: Retro Hardware AT dave ej hitchins DOT plus DOT com

dominicbeesley
Posts: 549
Joined: Tue Apr 30, 2013 11:16 am
Contact:

Re: Meanwell PSU in a model B

Post by dominicbeesley » Fri Jun 15, 2018 9:04 am

What brackets though? The only ones I've found were for a master case not model b. Thanks for the hint 're mark and cables, however i got all the crimp tools and connectors ac while bank and have made a custom loom with an extra molex connector and datacentre connector.

In the end the brackets only took 5 minute to make from some offcuts. Its a bit tight though. I could have moved the whole assembly forward a little more to clear the power switch but then the disc connector would be more difficult to fit.

User avatar
tricky
Posts: 2440
Joined: Tue Jun 21, 2011 8:25 am
Contact:

Re: Meanwell PSU in a model B

Post by tricky » Fri Jun 15, 2018 4:07 pm

Please post a photo as I might need to do the same thing. Don't worry if it is already installed, I'm sure someone else posted one somewhere, I just couldn't find it.

dominicbeesley
Posts: 549
Joined: Tue Apr 30, 2013 11:16 am
Contact:

Re: Meanwell PSU in a model B

Post by dominicbeesley » Sun Jun 17, 2018 10:50 pm

Hi Tricky,

I managed to forget to take pictures. The info here https://www.waitingforfriday.com/?p=794 is a big help.

I can't remember the exact dimensions but the brackets were made up from a couple of pieces of scrap MDF. I hand drilled holes and used 20mm long M3 machine screws to mount the new psu to the brackets with 3 nuts on as standoffs, I reused the old machine screws (I'm not sure of their thread?) to mount the brackets to the carcase.

I lined it up so that the front bracket had the single original screw hole in line with the two on the new PSU, it would have been better to offset the new PSU more forward to allow room for the rather large power switch and connectors at the back.

It's probably worth getting a proper crimping tool I got this one https://www.amazon.co.uk/gp/product/B06 ... UTF8&psc=1 and used the middle die set at the bottom of the first picture for the molex and inline connectors (0.5mm slot) which seemed to work well enough after a couple of practice runs (its worth over-ordering the terminals!)

D

Post Reply