TAB AND RETURN WORK WELL
Having freed up all the moving parts on the carrier and left of the frame, I have the tab function working just as it should. Similarly, carrier return works perfectly. Space will need an adjustment or more work.
PUSHBUTTON ADJUSTMENT WARRANTED
The three pushbuttons (Tab, Space and Return) are not pushing the actuator rods far enough down to reliably trigger an operational clutch. I can see that they need adjustment to provide more contact and more travel.
The pushbuttons are connected to the operational area by thin metal cables protected by outer sheaths. These transfer the inward push of a button to a downward pivot of the arms that push down on the actuators. The sheaths are anchored by a plate which is screwed down to hold them in place. By moving the sheath in or out a bit, one can adjust the movement of the arms.
In fact, I found that one of the two screws holding the plate down was loose, thus the sheaths must have backed out a bit over time. The only challenge in working with them is that the axis of the screw is directly behind many parts, so that a screwdriver can't be inserted to turn the screw.
The last time I had to adjust the plate on a Selectric, I had to disassemble some of the parts that blocked the path so that a short screwdriver could fit inside to loosen and tighten the screws. I will decide how much I need to do since it is essential that I adjust the position of these sheaths.
THE DISPLAY PANEL HARDWARE REMAINS MY MOST DESPISED PART OF THE MACHINE
Not only do I have to contend with the wire lead bulbs which are snapping off at the glass envelope every time I pull a row of lamps out to work on those that don't light, but the dark positions can also be caused by three other issues.
The bad solder joints on the PCBs holding the SCRs and bulb mounting pins cause many a position to not light with the Lamp Test because of connectivity errors. Often this also means they won't light when their associated signal is on either. Some pins refuse to solder nicely to the thin traces.
A few of the SCRs are dead - probably shorted out in the past during maintenance activities and not replaced since the system was ready to be decommissioned years ago. I have to unsolder them, unsolder a donor SCR from an unused position (CE lights) or my own display panel boards, then add the new SCR to the PCB.
Finally, the signal pins can snap off from the repeated bending of the signal leads moving around as they are unhooked and hooked to rows being worked on. I had another pin snap off today and this will require me to again excavate the plastic housing to expose metal, then solder on the broken pin.
I have plenty of LED replacement bulbs, but when the position is bad because of solder joints, dead SCRs or broken pins, it doesn't restore that position to lighted operation. I really want to get all the positions lighting as this makes debugging of the machine so much easier, plus the machine should have all its blinking lights working if it is restored.
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