Jupiter - effects PSU - ENG+ SLV

It all started, when Čič came for a visit and I've been boasting with my newly done "sand" effects. And he wanted to try "TT Banana booster" too. So he went to plug the mains adapter to the effect to try it. I saw the mistake at once, but it was too late - he's put the Banana adapter into on of the sand effects, the overdrive. There was a loud pop and distnictive smell of an exploded cap. And surely nothing from the unit anymore. Not only was it the polarity mismatch, there were 14V instead of 9. I knew it was a disaster.
But in the meantime I have learned with the TT Voltage pump failure, that passive parts are not so prone to failure (except the said mispolarization of elko caps) - and there are not much active parts in this circuit; so first I replaced the main cap, which exploded. Then I removed and tested both bigger diodes in the circuit (smaller diodes, which were in the circuit for the purpose of overdrive clipping, werw in such a polace that it looked impossible to be damaged by the failure), but they tested ok, so I soldered them back. The heart of the effect was an opamp, and it was available on eBay, so I oredred the replacement. Put it in - and it worked!
But still, the mechanism of the mistake was bothering me, so I decided to make my own effect PSU with so clearly marked connections to never do such a thing again (?). There were components, which weren't suitable for pure ptp wiring, and I really didn't feel like etching, so I kind of invented my new circuit making way - using rivets, solder lugs and laid wires on a board without copper. And as there is no "signal" wiring, hardly anything would go wrong.

BOM:
- ordinary board for etching, etched all copper off, cut to the size of the chassis
- computer PSU chassis - in the making I experiment with HCl and H3O, to get the "dirt" effect, thus the name of the device
- salvaged central tapped trafo, I think it is 15-0-15VAC, VA unknown, but I have marked it when salvaging to be 30W safe (from the device sticker)
- power common cahtode diode - i like it how simple is it to make a full wave rectification with such diode and central tapped trafo
- 6800uF 63V cap - surely an overkill, but I wanted to be on the safe side + I wanted to try to attach a snap-in cap with my methode - it worked great
- 1uF caps (3x) to paralell the existing elkos - main cap, both exit caps
- two DC/DC buck modules
- LED with corresponding resistor and its socket - when attaching I see it is not a critical thing and solder its ground directly to the chassis
- fan - At first I used it only to cover the hole in the chassis, but then the trafo was getting warm, and it was a nice idea to have the cooling on hand, so I connected it. It is a 24V unit, so it's nicely quiet and slow
- copper net for the chassis openings, fixed with rivets
- fuse bracket and fuse
- wiring - done with ease on the riveted solder lugs

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- zadeva dela - testirano čez noč teklo vse kar imam efektov; morda bi dolgoročno stestiral še pri polni prkilopljenosti z osciloskopom glede vzorca motenj.
- ohišje v "dirt izgledu" - fora s škropljenjem hidroksida z razpršilcem ni dobra, pravi bruniran look dobim le, če s hidroksidom polivam (zadnja obdelana stranica) - ampak še vedno izgleda kul.
- hcl+h2o2 skorajda v trenutku očistita ploščo bakra - je pa že majhna sled lepila dovolj, da baker ostane (morda bi bil to še boljši način za jedkanje plošč od Fe3Cl - ampak jedkanje plošč ni prav aktualno trenutno) - drugačew so te plošče krasne za izdelavo, in po mojem izračunu cenejše od fiberboarda s tt; moral pa bi najti še nadaljnjo alternativo, ki je verjetno še cenejša (1,6 ploščo, ki je neprevodna, nestatična in dovolj trdna)
- clip-on brusilkica za dremelj se res dobro obnese - noro dobro; kako hitro se da delat!
- design z rivets & solderlugs je sicer malce zamuden, ampak izjemno estetski in uporaben. Manjše rivets komajda pridejo skoz plato; za manjše rivets solderlug obrnem naokrog in dam rivet skozi luknjo za žico, žico pa skozi luknjo za rivets- pritrrditev dc/dc modulov s trdimi napajalnimi žicami se odlično obnese
- najprej delam GND povrh in DC spodaj, ampak je logično in bolje, da gre dc po vrhu in GND spodaj (torej ob ohišju) - morda bi za naprej veljalo DC še izolirati (heatshrink)
- vse gre tekoče in brez posebnih problemov
- trafo se greje (kasnejša inštalacija ventilatorja to vse zrihta)
- v noči dam mains na output od modula in ga skurim, jao - nov modul (ampak, saj so poceni); me pa šele ta incidemt opozori, da GND ni potegnjen na ohišje - naredim tako, da je (kot v profi inštalacijah, haha) to storjeno preko pritrdilnega vijaka ploščice) - je pa fajn, ker vidim, da menjava modula poteka hitro in gladko
- voiltažo 9 modula dam njaprej na 9,4V, ampak jo potem dam kar na 9,0, ker verjetno tolerirajo efekti tudi malo premalo (če bi že glih blo)
- ko se odločim dati outpute na stran pri stikalu, je ledica prekratka; najprej jo pustim kar noter, nato pa potegnem do mains inputa - ledice imajo, ker niso kritične v sistemu, vedno lahko gnd kar z ohišja ...
- ventilator - 24V ventilator krasno dela na 12VDC, ravno prav je upočasnjen; noter ga dam, da zapre luknjo v ohišju, ampak potem krasno funkcionira
- uf, kako je fajn pravzaprav delat s central tap trafotom, za full wave ne rabš drucga kot eno common cathode diodo, pa še trafo je ozemljen.
- s solder lugsi se res elegantno in hitro cini, potem ko je reč zvrtana in pritrjena - se obnese! - tudi resoldering je hiter in brez problema
- dober je ta koncept, da je vse na plošči in je tako cinjenja ohišje - notranjsot minimalno
- priotrditev izhodnih kablov s penico je fajn

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