Verifying all circuits driven by the repaired 3819 SLT card; still a couple of issues

SWAPPED IN NEW TANTALUM ON THIS CARD

Because the IBM Tantalum capacitors, rated at 60V, have failed once in this machine and once in a machine in Europe, they don't appear to have enough margin for the poorly regulated 48V DC rail used with solenoids in the machine. I bought a modern 75V rated part to install in 3819 cards which need the 48V rail to absorb back EMF from solenoids they are activating. 

Card with new axial tantalum installed

An IBM 1130 system has at least three 3819 cards, two used to drive the 1053 Console Printer (typewriter) solenoids and one to drive various 12V lamps and a 48V keyboard solenoid. 

Every solenoid in the 1053 typewriter has quenching diodes installed so the 3819 cards for the 1053 do not need access to 48V. It is provided only because the standard card includes this. When I look at the location where the typewriter's 3819 cards are installed, I can see that 48V is not hooked to the card's pin whereas the card which failed has it in order to quench the back EMF of the keyboard restore solenoids. 

When paper tape peripherals are installed, one or two more 3819 cards will be configured in the 1130 system. The VCF machine has the controller for a paper tape reader installed, thus a fourth 3819 card in this machine. It too has 48V supplied to it, so I switched the tantalum to my new 75V part for safety. 

CHECKING ALL LAMPS OPERATE PROPERLY

I was able to check that the Forms Check and KB Select lamps light since I can change the conditions to make this happen. Previously the Parity lamp was seen to light but very dimly. I hadn't seen the Run nor the File Ready lamps illuminate. The KB restore works just fine as well. 

File Ready will only come on when the disk controller sees a disk up to speed with the heads properly loaded. Since the drive is removed now for restoration, this won't happen naturally. However, my grounding the signal line coming to the 3819 I could see the lamp glow as it should. 

Run should light when the CPU is not stopped. It should also blip when I single step instructions. I has not lit. Grounding the input pin does produce a good glow from the lamp, so the issue is upstream in the logic.

The dim Parity lamp circuit is different in that it has a 0.22uf capacitor to ground across the lamp output. I suspect that this capacitor may have a leakage that is dividing the current, producing the dim light. I will experiment with an alternate capacitor. 

However, I also notice that both the Parity and the Run signals come in on a cable at connector N6 thus an issue with the connector seating or an issue with the continuity from the driving logic all the way to the 3819 might be responsible. I will be checking this in an upcoming session.