Altair, IMSAI, SWTPC, etc. for sale in Philly

[Sam O'nella]

Out of curiosity and ignorance what's with the solder joints on the cards in the pictures? That orange color seems like it's everywhere around cold looking solder joints.  Is that rust, some sort or protection, or acid corrosion?
-------- Original message --------From: Mark G Thomas <Mark at Misty.com> Date: 10/31/16 
I had the pleasure of visiting Rick yesterday. Please see below 
additional information about remaining items, with links to photos.
Please contact Rick directly if interested.

Original posting here:
On Tue, Oct 18, 2016 at 08:44:39AM +0000, steven stengel wrote:
> ---------------------------------------------------------------
> *************  Contact Rick below if interested.  *************
> ---------------------------------------------------------------
> Name: Rick Bunker
> Contact: rick at bunker.us
> Location: Jenkintown, PA    
10/30/2016 Update:----------------------

> The Altair 8800, a very early one, 4-slot motherboard, 1K ram, ceramic CPU,
> you will see: https://goo.gl/photos/3C1pzfwFoZ3koPgt9
>