| Three Jeeps <jjhudak4@gmail.com>: Nov 16 05:25PM -0800 On Sunday, November 14, 2021 at 7:20:46 PM UTC-5, John Keiser wrote: > Am I on the right track? > What should I do next? > Thank you for any advice. the PS outputs 150V, +/-12, +5 vdc. Do they *all* drop 50%? All rise 15% no load? If so, that suggests a bad transformer or perhaps a bridge rectifier lost a leg. a scope would help with diagnosing the rectifier. Actually don't even need a scope for the BR. DMM will work. Looks like everything else in the PS can be troubleshot with a DMM & ESR meter for finding bad caps. BTW IC u1212 is a TA7179 (not 7199)but it is a dual track regulator. Interesting that they use the sense lines. J |
| Michael Terrell <terrell.michael.a@gmail.com>: Nov 17 07:11AM -0800 On Tuesday, November 16, 2021 at 8:26:01 PM UTC-5, Three Jeeps wrote: > the PS outputs 150V, +/-12, +5 VDC. Do they *all* drop 50%? All rise 15% no load? If so, that suggests a bad transformer or perhaps a bridge rectifier lost a leg. a scope would help with diagnosing the rectifier. Actually don't even need a scope for the BR. DMM will work. Looks like everything else in the PS can be troubleshot with a DMM & ESR meter for finding bad caps. > BTW IC u1212 is a TA7179 (not 7199)but it is a dual track regulator. Interesting that they use the sense lines. I misread the part number on the schematic. I am currently waiting for cataract surgery on both eyes. The other voltages are referenced to the +/- outputs of the TA7179P. I've never seen a regulator with tracking inputs that could be left floating. Via email he said that there is 40 volts of ripple at C1213. |
| Edward Hernandez <dtgamer99@gmail.com>: Nov 16 07:28PM The John Doe troll stated the following in message-id > The troll doesn't even know how to format a USENET post... And the John Doe troll stated the following in message-id <sg3kr7$qt5$1@dont-email.me>: > The reason Bozo cannot figure out how to get Google to keep from > breaking its lines in inappropriate places is because Bozo is > CLUELESS... And yet, the clueless John Doe troll has itself posted yet another incorrectly formatted USENET posting on Tue, 16 Nov 2021 14:53:35 -0000 (UTC) in message-id <sn0glf$vk$1@dont-email.me>. U2W+WJi4KPlT |
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