IBM backplane story was Re: Another 780 backplane story - cctalk

6 Jul 2025

I worked part time at a computer center for a large bank while getting my undergraduate
degree.

The center was getting one of the first IBM 3081 machines to replace the existing 3033
MP.

Because of the helium filled modules, getting the machine from the climate controlled
truck to the center, which was on the 7th floor of the bank building was crazy; the move
had to be accomplished in 30 minutes. As a dry run, IBM supplied a size and weight dummy
3081 in advance to make sure the delivery went smoothly.

As you might imagine, the install and switch over to the 3081 was high profile. The VP in
charge of the center was under pressure to get it done on schedule.

The delivery and initial install went according to plan. The data was migrated to the new
disks and the various application software was run through its paces. 

Unfortunately, the 3081 would occasionally throw a power fault. The local FE’s could not
determine the cause, so after a week or so second level support was called in. They could
not figure it out, so IBM brought in Ivan (I think that was his name). You know when you
get the hot shot from IBM when he arrives in bib overalls and tennis shoes, not a suit and
5 pound wingtips.

After the second day, Ivan got tired of the stream of managers asking him when the 3081
would be available, so he went down the the main bank floor and grabbed the thing (I
cannot remember the proper name) banks used to use to create teller lines (posts and satin
“ropes”), and formed a cordoned area around the 3081’s console. Note that each computer
console had a telephone (1 for each 3033 and one for the new 3081) for communicating with
the computer operator.

On the third day, the VP bypassed the cordon and asked Ivan when the 3081 would be
operational and Ivan replied he was’t sure. The VP said he had already told the president
it would be up by the end of the day, and Ivan handed the VP the phone on the console and
said, and I quote, “Call someone who cares”. I kid you not, I still remember verbatim.

Early afternoon of the third day, Ivan asked the Lead FE to get a torch. There was an
awesome hardware store about 6 blocks away, so in about 20 minutes the torch was
delivered. 

The power bus on the 3081 had enormous cables composed stranded 4-6 large gauge wires that
were soldered to large metal plates. Ivan had determined that the wires were improperly
soldered and used the torch to resolder them. 

You can imagine the horror on the faces of the staff as Ivan opened the power bay, lit the
torch, and started melting the solder.

And it worked! No more power faults.

— Todd