Working on my 1442 card reader/punch

MY 1442 WAS NOT FULLY FUNCTIONAL

My card reader/punch had a number of issues that were outstanding. Once I implemented my virtual peripheral device using the Storage Access Channel feature on my 1130, I could feed cards from virtual readers based on files on a laptop and left the 1442 for a later repair session. It will be very useful if I can get it working so that I can fully test the logic in the VCF 1130 that controls a 1442. 

The card movement was a bit pokey, due to residual gummed up lubricants in the moving parts of the reader. It would feed and read a card, but either gets a read error or a feed error right away. It also moved the cards so slowly that they failed to 'corner' on the path to the output stackers.

This device has a continually running motor with a feed clutch that is energized to move cards from one station to the next. During a feed cycle, the read clutch is tripped to move a card through the read photocells. If the card has not reached certain points when timing pulses from the motor (feed CBs) arrive, the controller detects the read or feed error. 

Another issue is dealing with the lamps that show the device status. The 1442 reader was first designed as part of the IBM 1440 system, part of the Standard Modular System (SMS) of the 1950s that preceded the Solid Logic Technology (SLT) generation in the 1960s for System 360 and the 1130. I absolutely hate the lighting displays from SMS, which were carried over for the display light panel of the 1130 system and for the console of the 360 model 30. All the others used the SLT version which are much easier to deal with. 

The SMS approach uses wire lead incandescent bulbs fitted into nylon holders. The holders have two brass cylinders on the back, into which pins are pushed. The holders are themselves pushed into a plastic honeycomb. 

An SCR has a pin that is pushed into one hole of a lamp holder, the other hole has a metal pin pushed in to deliver the common side of the connection. These are in fact inherited from the pre-computer punched card machines, miserable pins that don't fit easily into the holes. They either require brute force to push them in, but the least bit of corrosion on a pin or frankly even the phase of the moon can make these barely able to enter the hole. 

Each SCR and common pin is manipulated individually in tight quarters. Push in one pin, the torque on the common wire causes another pin to pop out of its holder. Just like with the 1130 display light panel, this becomes a game of whack-a-mole, producing a ton of frustration. The job of replacing burned out incandescent bulbs takes far longer than necessary because of this poorly designed mechanical system for the lamps. 

Inside the 1442, the indicator lights are a delight

I converted all my lamps over to LEDs, where I solder an LED plus a limiting resistor and fit that inside the nylon lamp holder. I use 26 ga copper wire which is similar to the leads of the original incandescent bulbs. 

The original incandescent bulbs have their wire corrode at the junction with the glass envelope, becoming brittle and then snapping off at the least of provocations. Many more bulbs failed due to broken wires than burned out. In trying to replace the broken bulbs, I wasted a few hours and never got the light panel back together. 

Now I get to finish this task - what a joy. 

The final issue with my 1442 is that the punch unit is broken. It has two wheels with ceramic grit that bit into punched cards to move the precisely one column at a time as the card is being punched. The ceramic broke on the wheels and I was unable to repair them in the past. 

Fortunately, a very kind organization presented me with a replacement punch unit from a 1442. I just have to pull out the old broken one and install the replacement.