Hi Stephen, [I didn't (re)read the whole previous repair story.] Are you sure now that the sweep generator itself is not the problem? If A and B sweeps show the same problem then the problem is likely

Jeff, The pulse rise time at the scope input gets (with such a fast generator) determined by the effective RC at the scope input. Without terminator that will be 1 ns, with terminator 0.5 ns. That cor

Jeff, note it's 067-0625-00. Albert

The 74S387 is already obsolete in 1984 TI TTL Data Book: "contact the factory for abaility " and "has been superceded by the TBP 24S10". Albert

I see Stephen. It's good to set R544 and R566 first and do steps 24 and 44 after that. Steps 24 and 44 have no effect on sweep speed, only on sweep length. Albert

Hi Stephen, Which pots do you mean? Sweep lenghts are determined by internal trimpots in the Miller run-up circuits, calibration steps 24 and 44. Is time/div OK or also expanded? Albert

Search or "547 V800". Albert

Thanks Cristler, this must have been a lot of work! I like the extensive description in the README.md file. I guess I dis similar things (also in Python) in a far less sophisticated manner and left th

Jeff, You might already check that the feedback circuit stays in regulation. The cathode voltages of V83 should vary when you vary the VAR amplitude and of course when you rotate the amplitude switch.

Hi Stephen, It's a relief of course that the unit is now working again. Still I don't understand why. I read this as if you connected "everything" to pins 6 now and left pins 9 unconnected. This is fi

Stephen, It's still an open question what's going on here. Later on you checked S242B, but did you also check that the wiper of R246 is not open circuit? Albert

Stephen, I would say don't! Even if 3 resistors are open and one is 10 k you would have higher output amplitude than what you found. All 4 resistors open might occur I think when R99 is open and no lo

Hi Stephen, So you have -161 V at pins 3 of the output tubes, but hardly an output signal. When there is no nearly short circuit somewhere in the output wiring this means that the output tubes draw ju

Jerome, The Factory Calibration calls for 20 degrees. But remember that this is merely a preliminary setting before further tuning of T1 is done with the S-30. If the latter works (meter can be zeroed

If not yet mentioned: the tek_type_130_factory_cal_proc.pdf also has the instructions for tuning T1. T1 is done before the S-30 comes into play. Albert

Stephen, some time ago there was a problem with S242B. The switch seemed to be closed all the time. I assume your reading now is still in High Ampl mode. Then it looks like the opposite failure of S24

Don't bother about Q224/Q227. That -25 V in the schematic is simply wrong. The "A" voltage is -7 V in the schematic, hence the base of Q227 should be some 0.6 V more positive, -6.4 V. I measured -6.4

P F, The essential specs of UZ5215 and 1N5383 are the same. The 1N5383 should be good enough for normal functioning of the 106. Any strange values might be due to previous collateral damage to other c

Stephen, if you are not familiar with those multi-section canned caps fig.4 might look confusing to you. The outer 3 "terminals" actually are twist lugs of the metal can and also serve as common minus

Stephen, The current situation is that "A" reads -5.5 VDC and that this voltage doesn't go more negative when you increase Amplitude. Right? The differential voltages "A+150V", "A-150V" and "A-20V" ve