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WANTED! P3A Amp heatsinks!

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This may be a long shot but is anyone out there blessed with two heatsinks that are the right size (and preferably pre-tapped) for 2 P3A boards? [Around 1Deg C per Watt 170mm*80mm]

I would be greatful for any replies - I'm from the UK so preferably no replies from too far away (unless you know some way to post heavy items gravity free!)

Thanks for looking

:D
 
heatsinks

Hi,

If you can't find anything more exactly suitable, I have some heatsinks available. Here's a description I gave to someone else:

"My calculations and comparisons with other heatsinks seem to indicate they'd be more like 1C/W, though. That is conservative actually, as they look pretty identical to the one that is rated at 0.9 or 0.58C/W in the (1997!) RS catalogue I have. They are 150 x 200 mm (the 0.9C/W in RS was/is 125x200, and the 0.58 C/W was/is larger than these). There are 29 fins which run parallel with the short dimension which are 25mm long (actually 21mm ignoring the base thickness). I'd guess at 0.8 C/W or there abouts... They have a threaded hole near each corner (so can easily be turned into square enclosures with a little aluminium angle), and are drilled and tapped (twice) for transistors either side of the midpoint of a line running down the middle. Ideal for flatpacks, but TO-3s would require more drilling or a bracket. My only reservation with them is that they are powder coated (black) rather than anodised, and if they are dropped the coating on the edges of the fins can chip."

A tenner each, I'm in London.

Cheers, Jake
 
Sorry, no pics and no way to take any.

Rarkov did a render from the description which I've tried to attach. Pretty damn acccurate, if you can imagine them black!
 

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I highly recommend dealing from this guy - I bought two of these heatsinks and paid via PayPal and they were at my house before 9 the next morning!

May I say a pleasure to deal with you - also if you ever have anything else laying around be sure to post on the forum and email me first ;) .

If anyone has any queries buying goods over this forum I would happily reply emails with regards to the good service I received.

:D
 
Thanks Annex and Rarkov,

Rarkov - if you want replacements for the chipped ones, let me know. I did check them before sending, but I guess I didn't look closely enough. Apologies anyway, but if you do want replacements get in touch.

(that is the down side I warned of of the powder coating/paint, whatever they used appears not to be totally robust on the fin ends, and slight chips occur pretty easily. I once stacked up a whole bunch to see what my planned case would look like, it collapsed and I have a bunch of chipped ones. As you say, luckily a marker pen makes it invisible to anything but microscopic attention.)

Cheers, Jake
 
Hi Jake,

Don't be silly - I couldn't get them this cheap anywhere else! They're great! I've planned them so that everything fits in perfectly (500VA tranny, 4x6.8mF caps, 2x35A rectifiers, circuit, 4xMOSFETS)...

Anyway - It's only maplins I cause hell for! (Our version of Radio Shack if non-UKians didn't know)

I'm trying to think of a nice thin plank of wood to cover the top,bottom,front and back with...Not sure yet...It may well be clad with aluminium yet!

Gaz
 
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