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 > > >
