andrewb
Well-known member
The large Elna filter caps on the deflection board are almost certainly ok. (I was referring to the ones in the HV cage.) Those large caps don't naturally go bad like the small ones do (and they can be a little pricey), so we typically don't replace them during a recap, unless they're physically damaged.
If two of the heatsinked transistors are testing bad, you may have other issues (possibly, but not guaranteed). You should test all of the diodes also in that area, as a shorted one with sometimes take out the transistors.
The MPSU-07 and -57 transistors can be replaced with more modern substitutes. See Bill's page for details:
http://www.biltronix.com/transistor_subs_01.html
I use the ZTX653/753's, but they take a little work to install. You have to get the correct heatsinks for them (also on the page above), and drill holes in the heatsinks, to bolt them to the larger sinks. Also, the orientation of those transistors is opposite of the original ones (see the datasheets and the PCB markings to align B, C, and E). But once you take care of these things, they work well, and are super cheap compared to the original parts.
If two of the heatsinked transistors are testing bad, you may have other issues (possibly, but not guaranteed). You should test all of the diodes also in that area, as a shorted one with sometimes take out the transistors.
The MPSU-07 and -57 transistors can be replaced with more modern substitutes. See Bill's page for details:
http://www.biltronix.com/transistor_subs_01.html
I use the ZTX653/753's, but they take a little work to install. You have to get the correct heatsinks for them (also on the page above), and drill holes in the heatsinks, to bolt them to the larger sinks. Also, the orientation of those transistors is opposite of the original ones (see the datasheets and the PCB markings to align B, C, and E). But once you take care of these things, they work well, and are super cheap compared to the original parts.
