I must admit, by all appearances I've fallen for a false etymology.. at least so far as having origins in WWII slang. Depending on how you view it, the origin of 'jerry-rigged' is either much older +or+ slightly newer..
Here's an interesting and somewhat detailed discussion: https://english.stackexchange.com/questions/132868/jury-rigged-or-jerry-rigged/132919 As for the PSU, that drifting gain voltage seems to be a major clue. Where does this voltage track in the known-good unit? Have you also verified that all of the precision voltage references / zeners / etc. are themselves stable and not drifting? Is the voltage generated by the controller chip, or supplied to the chip from an external reference? On Sun, Aug 20, 2017 at 1:24 PM, Hagstrom, Paul <hagst...@bu.edu> wrote: > As far as I know, the relevant ('temporary/improvised') concept is > generally accepted to be (or at least originally to have been) > "jury-rigged." > > https://en.oxforddictionaries.com/definition/jury-rigged > > http://archives.cjr.org/language_corner/the_jury_is_in.php > > Nothing to do with WWII, though perhaps the convenient near-homonym led to > a separate, later usage through mis-hearing the original usage. At best > both are "correct" for the concept, conservatively/prescriptively only > jury-rigged is. > > We now return to troubleshooting the Atari PSU, already in progress. > > > > On Aug 20, 2017, at 2:01 PM, drlegendre . via cctalk < > cctalk@classiccmp.org> wrote: > > > > Arrgh! /Jerry rig/, not Jury rig! Jury rigging is something entirely > > different.. > > > > The former comes from WWII era slang, when German soldiers were called > > 'Jerries' (among other things); see Jerrycan for instance. As has often > > been the case, as the war drew to a close and the supply chains broke > down, > > everything needed to run the army dried up, hence the need for quite a > few > > "field expedient" (read: improvised) repairs to machinery and weapons. > > > > And I don't think they even had duct tape in those days, did they? More > of > > a bailing wire era, one would suspect.. > > > > On Sun, Aug 20, 2017 at 12:15 PM, Adrian Graham via cctalk < > > cctalk@classiccmp.org> wrote: > > > >> > >>> On 20 Aug 2017, at 16:32, Mattis Lind <mattisl...@gmail.com> wrote: > >>> > >>> > >>> > >>> söndag 20 augusti 2017 skrev Adrian Graham via cctalk < > >> cctalk@classiccmp.org <mailto:cctalk@classiccmp.org>>: > >>> Hi folks, > >>> > >>> I think I’ve mentioned this PSU before but the question I have might be > >> applicable to other cheap switchers. This lump for the original Atari > 520ST > >> is run by an NE5561N control chip with a D45H1 switching transistor. > It’s > >> supplied by a multi-tap transformer giving 2x2 feeds of 6VAC and 14VAC > with > >> an eventual output of 5V@3A, 12V@30mA, -12V@30mA. > >>> > >>> This one will run under load for around 10 minutes then the 5V rail > will > >> gradually collapse over the next few minutes. Turn it off and leave for > a > >> minute or so and it’s back to normal, repeat as above. > >>> > >>> Heat related? Try freeze spray to check if it recovers or stays > working > >> longer. > >> > >> I need to jury rig something with a breadboard to allow me to run it > >> outside the enclosure, in normal usage it’s solder side up with the > >> components covered. I can’t remove the transformer lump because it’s > sealed > >> in resin. They really didn’t want people to attempt to fix these things > :) > >> > >> > >> — > >> Adrian/Witchy > >> Binary Dinosaurs - Celebrating Computing History from 1972 onwards > >> > >> > >> > >
