1053 pull links done, connected SAC enhancement into 1130 backplanes

1053 CONSOLE PRINTER RESTORATION

I tackled the broken swing-arm pivot screw, looking to put together an equivalent from a longer hex head bolt, nut and a bit of hollow tube around which the swing arm pivots. The original part is a hex head screw with a stepped diameter, the part closest to the head being a smooth cylindrical section to allow rotation and then the stepped down remainder is threaded to match the nut.

The dimensions of the very short hollow tube are important. The outer diameter has to match the pivot arm to allow smooth rotation. The inner must be large enough to allow the hex head bolt through. The length has to be slightly larger than the pivot arm thickness, allowing rotation but not any cocking of the arm to the side. Finally, my bolt has to be a good length, to fit over the hollow tube, through the bracket assembly, and allow the nut to affix but not extend too far past the outer face of the nut.

I picked up a set of hardware from a local store but it was not good enough - outer diameter too small and the threaded part too wide. I will keep at it, until I find a suitable combination. Not sure how the machine will work without the pivot arm and the switch operation, but I will probably find out.

Meanwhile, I attached two more pull links, but one came off. Tedious and extra hard because there is zero visibility to the area where the link attaches, unless I disassemble my shift mechanism and lose those adjustments. I refuse to pay that pound of flesh so it goes slowly.

Finally by early evening, all five pull links are properly attached and releasing the mechanisms when the solenoid arm is activated. I will do some fine tuning of the adjustment pressure but all five are operating pretty well right now.

Fixing the pivot arm attachment and repairing the ribbon color activating tape are left, plus adjustments, testing and cover/faceplate installation. I can see the finish line from here.

SAC INTERFACE FOR ADDING PERIPHERALS TO THE 1130

I dressed the wiring that runs down inside the 1131 to the backplanes, soldered on push-on ends, and used heat shrink tubing where necessary. Cable ties held the lines neatly as well, allowing for movement with the full swing-out and swing-in positions of the two gate frames. All the lines are pushed onto the respective pins on the backplane.

Push on ends added to the twisted pairs

Example of one twisted pair added to the backplane

I then had to fasten the lines to the fpga in the SAC Interface Box, since they are now wired into the 1130 system. Updated logic was written to the fpga to handle those lines. My python PC side program is updated to display and set the two new interrupt levels, so that I could test my circuit and wiring.

The DC-DC converter board came in today and was wired in. A bench power supply provided the +6V for the converter, whose output was the 5V needed by the daughter card and other boards I have inside the 1131. Since that works, I will wire the converter into the +6V SLT supply lines and mount the converter board in a suitable location.

DC-DC converter in operation converting +6V to +5V

I picked a location to mount the 'emulation engine' board which activates relays in a timed sequence, the relay board that virtually pushes the three buttons, and began to wire everything into place. I have a bit of wiring to do to hook the four relays into their three button circuits, plus the power lines will be finished once I mount the DC-DC converter board somewhere.

Approximate location of the emulation engine and relay boards

If I get the DC-DC converter wired to the SLT power supply and at least the daughter card fully functional, I can do some power-on testing of the system. The Program Load function of the emulation engine and relay board can be finished and tested independently.