[Milsurplus] GRC109/R-1004A arrived!

[WA5CAB at cs.com]

Heatsinks are generally made of aluminum.  Black ones are not painted.  
They are black anodized.  If they aren't black, they are still anodized, but 
clear matte instead.  A painted surface, regardless of the color, would 
degrade the heatsink performance.

In a message dated 09/14/2011 19:15:55 PM Central Daylight Time, 
jphutch60bj at gmail.com writes: 
> All -
> Black heat sinks seem to dissipate, distribute, suck off, more heat from 
> the device; when looking at the heat sink specifications.
> I believe units painted  the Black in WW2/Korea/Viet Nam was:
>   1. cheap paint.
>   2. for light, reflection, glint, abatement
> Now I could be wrong.... being anything with a tube ran hot anyway.
> Hutch
> 
> 
> On 9/14/2011 9:23 AM, bcarling at cfl.rr.com wrote:
> >Every piece of solid state power equipment I have ever used with a heat 
> sink has it colored black. With a few exceptions for on painted aluminum 
> surfaces, that is about it. Engineers have used this technique for about 40 
> years or more. No they usually do not run hot enough to melt solder.
> >   I am fairly sure that the engineers who painted the grc109 boxes black 
> did so for a reason.
> >
> >Sent from myTouch 4G
> >
> >----- Reply message -----
> >From: "J. Forster"<jfor at quikus.com>
> >To:<bcarling at cfl.rr.com>
> >Cc:<milsurplus at mailman.qth.net>
> >Subject: [Milsurplus] GRC109/R-1004A arrived!
> >Date: Wed, Sep 14, 2011 9:41 am
> >
> >
> >Painting the heatsink black is essentially pointless. Unless the heatsink
> >operates at high temperature...  think melting solder at least...
> >radiative transfer is insignificant.
> >
> >-John
> 

Robert & Susan Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480