Talk:ADM-3A
From Wikipedia, the free encyclopedia
[edit] Metal cage? Rugged??? Say what?
I seriously question the second sentence of the article.
one of the most rugged chassis ever to be employed in any computing equipment, being constructed with a very thick metal frame (over an inch at the thickest bits).
I believe that the case is not metal, and the word "rugged" is not correct.
I have two of these terminals, and I repaired many in the early 1980s. All of the ones that I've seen had lightweight plastic cases. I remember reading that they are Bakelite.
These things are not "rugged". While collecting the two that I have, I received one that was destroyed during shipping when the weight of the picture tube caused the top of the clamshell case to snap. I'd use the word "brittle." From my early repair work, I've seen that the majority of the weight is in the vacuum picture tube and in the large laminated-steel-core Transformer.
Finally, the density of the "thick metal frame" would put the weight far over the mere claimed 32-lb weight. I have a milling machine. Believe me. Just the vise for the mill weighs 42 lbs, and it has much less metal than the case would have if it were cast metal.
So, here's what I've been able to find. In a copy of the maintenance manual one reads that the case is "molded" and that the weight is 25 lbs. An operators manual says that the weight is 32 lbs. There were at least two versions of this terminal. The later ones used integrated chips and probably had a smaller transformer. The earlier ones had a board full of TTL chips, which would have required a larger transformer. So it's possible that both references are correct.
KerryVeenstra 17:55, 12 November 2007 (UTC)