I finally got around to updating the capacitors. I used kj7e's list. I had been repairing something else, and it had been a while since I used the 53310A, so of course I got all kinds of failure codes and information when I turned it on. There was less and less for the next couple power cycles, so it was clear that it was time to check it.
First I removed the power supply and I connected to the 20-pin output connector to monitor all the voltages. I started with a 40W bulb for the dim-bulb limiter, but I had to switch to 60W. A few were low, and after a couple power cycles it got worse and worse. If I recall one of the 12V rails was having the most trouble. I tried to measure capacitance at the output connectors, but my LCR meter could not settle on a reading.
I ordered the parts from Digi-Key, so in the meantime I removed the old capacitors. Several were leaking and I cleaned up the electrolyte as I could. I only delaminated 3 or 4 solder pads on the top of the board, and none of the tracks delaminated. None of the tracks were corroded enough to require repair.
After installation of the new capacitors I ran it on the bench and monitored all the outputs. It wouldn't run with a 60W bulb, so I switched to 300W. That almost worked, so I ran 60W and 300W in parallel, and that worked. All the outputs were fine, so I reassembled the machine and ran the self-test. All tests are fine, although note that the oven takes a while to heat up enough to pass.
Here are the measurements of both the old and the new capacitors out of circuit. Most were measured at 1000 Hz. The large values were also measured at 100 Hz.
Note: The list from kj7e calls out one of the 2200 µF as C25, while I list it here as C42. The designations on the board are ambiguous in that area.
Ref | f (Hz) | C (µF, old) | D (old) | Θ (°, old) | C (µF, new) | D (new) | Θ (°, new) |
C7 | 1000 | 866 | 0.5 | -63.4 | 857 | 0.386 | -68.8 |
C8 | 1000 | 879 | 0.514 | -62.8 | 851 | 0.378 | -69.2 |
C9 | 1000 | 827 | 0.47 | -64.8 | 849 | 0.377 | -69.3 |
C10 | 1000 | 856 | 0.48 | -64.3 | 863 | 0.373 | -69.5 |
C11 | 1000 | 862 | 0.487 | -64 | 853 | 0.366 | -69.8 |
C12 | 1000 | 850 | 0.489 | -63.9 | 859 | 0.367 | -69.8 |
C13 | 1000 | 872 | 0.501 | -63.4 | 861 | 0.358 | -70.3 |
C14 | 1000 | 841 | 0.477 | -64.5 | 856 | 0.36 | -70.2 |
C15 | 1000 | 851 | 0.52 | -62.5 | 864 | 0.359 | -70.2 |
C16 | 1000 | 836 | 0.508 | -63 | 860 | 0.348 | -70.8 |
C17 | 1000 | 355 | 0.732 | -53.8 | 451 | 0.205 | -78.4 |
C19 | 1000 | 23 | 2.42 | -22.3 | 43 | 0.097 | -84.4 |
C22 | 1000 | 596 | 0.408 | -67.8 | 569 | 0.395 | -68.4 |
C23 | 1000 | 600 | 0.422 | -67.1 | 583 | 0.37 | -69.6 |
C26 | 1000 | 5402 | 3.27 | -17 | 6414 | 2.51 | -21.7 |
C26 | 100 | 5471 | 0.384 | -69 | 6283 | 0.276 | -74.6 |
C27 | 1000 | 5203 | 2.73 | -20.1 | 6652 | 2.53 | -21.6 |
C27 | 100 | 5479 | 0.329 | -71.8 | 6457 | 0.276 | -74.6 |
C30 | 1000 | 880 | 0.508 | -63 | 869 | 0.358 | -70.3 |
C31 | 1000 | 826 | 0.476 | -64.5 | 856 | 0.351 | -70.6 |
C32 | 1000 | 897 | 0.476 | -64.5 | 861 | 0.354 | -70.5 |
C33 | 1000 | 908 | 0.475 | -64.5 | 856 | 0.35 | -70.7 |
C34 | 1000 | 190 | 0.448 | -65.8 | 219 | 0.099 | -84.4 |
C35 | 1000 | 163 | 0.673 | -56 | 232 | 0.097 | -84.4 |
C36 | 1000 | 177 | 0.462 | -65.2 | 218 | 0.097 | -84.4 |
C37 | 1000 | 159 | 1.1 | -42.4 | 219 | 0.095 | -84.5 |
C38 | 1000 | 179 | 0.536 | -61.8 | 222 | 0.097 | -84.4 |
C39 | 1000 | 190 | 0.465 | -65.1 | 216 | 0.101 | -84.2 |
C40 | 1000 | 1406 | 1.93 | -27.3 | 1929 | 0.711 | -54.5 |
C40 | 100 | 1820 | 0.355 | -71.1 | 1990 | 0.091 | -84.7 |
C41 | 1000 | 1292 | 2.06 | -25.8 | 1870 | 0.679 | -55.8 |
C41 | 100 | 1760 | 0.408 | -67.7 | 1920 | 0.086 | -85 |
C42 | 1000 | 1674 | 1.66 | -31 | 1923 | 1.41 | -54.7 |
C42 | 100 | 1900 | 0.213 | -77.9 | 1990 | 0.095 | -84.5 |
C49 | 1000 | 5219 | 2.33 | -23.2 | 6167 | 2.12 | -25.3 |
C49 | 100 | 5367 | 0.275 | -74.6 | 6345 | 0.252 | -75.9 |
C50 | 1000 | 190 | 0.476 | -64.5 | 215 | 0.1 | -84.2 |