There is considerable leeway. The calculated value is 1.25uF, and anything between half that and twice that is acceptable. Larger values give slightly deeper bass with slightly less power on the deepest bass - neither is likely to be audible in ordinary use.
I'll defer to PB on the wire. You can also ask at replacmentparts <at> bottlehead.com for the cable and capacitor. Mention this thread when you email.
Thank you for that, Paul. It seems that the options for caps increase a fair bit if 2uF is acceptable, so I might go with that. I'll keep the replacement parts thing in mind, too. It all comes down to shipping in the end.
That wire will do the job, the STP in the SEX amp doesn't carry much voltage.
Water soluble flux can ruin a build, but I have brought kits back to life by running them through a dishwasher cycle without soap.
Excellent. Thanks for that PB. Finding an equivalent wire down here in Oz is pretty much impossible - too small a market for many specialty products I guess.
Re the flux: yeah it was a lesson learned, for sure. The Keystone terminal strips were a bit oxidised and my wimpy no-clean solder didn't have strong enough flux to cut through, so I unwittingly added the water-soluble stuff. It worked in the short term, but then clagged everywhere, hid in places, and trapped forgotten lead cutoffs. The total immediate damage on first power on was one power resistor, a Dayton cap, and an RCA tube. It took out another tube before I got it clean enough to function, but it's not ideal and I'm looking forward to a clean slate. I have better RMA solder these days.
I've seen you mention the dishwasher thing before - how does that work exactly? Are we talking disassembling and desoldering and washing the hardware and passives? Or you just bung the whole thing in minus the wooden base and tubes? I always assumed that would destroy switches and pots and transformers and such.
I'm basically planning to bin everything but the transformers, chokes, tubes, base, top plate and mounting hardware, and replace the rest to rule out gremlins. This still leaves the possibility that I damaged the PT-10 when I (very gently) sanded the chickenwire marks & coating off the sides and repainted. I recall you folks telling someone this may damage the transformer - something about eddy currents? The transformer did get quite hot in operation, and there was a definite hum, but it also seems like these things are normal within certain limits. So maybe it's fine? I dunno if there's a test with a scope or meter or something to confirm.
Anyway, I can try working with the iron I have first - if I have to build it a third time I'm sure I'll have it down pat by then.
