Amp rebuilt with iskras & mustards

67plexi said:
PEC pot's are fine 10% taper I used them in my 6 Trainwreck builds

Ivan you were fortunate to find the parts you have.

Good Luck finding any good electrolytics now F & T Germany is as close as you going to find at a fair price.
Jensen made in Denmark are a good electrolytic.

Jensen Electrolytic Capacitors
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Thanks for the heads up re the PEC pots & Jensen electrolytics.
Yes, NOS componentsts are getting harder to find. I do have a complete set of Philips Mullard C296 capacitors, including two of the hard to find 0.68uf/160v caps, thank you very much again RVA. Also two complete sets of (correct wattage) Piher resistors, including voltage droppers, plus a few more iskras. These will come in handy for an upcoming '69 era 100 watt superlead build. I have the screen filter balance Piher resistors coming. Still looking for two 470~560pf dogbone caps. Cheers
 
syscokid said:
Slim pickings out there. What ya think about this ad:
Marshall JTM45 NOS Mica capacitor kit RS SRC LEMCO 560pf 250pf 47pf Radiospares | eBay
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Damn Sysco, I am tempted to grab them, a JTM45 build would be cool too & I do have the Piher resistors plus voltage droppers15462015206943231719271582476995.jpg and as well as the full set of mustards that RVA so kindly helped with, I have at least half of a JTM45 set (would need a few more 0.1uf) 15462018987725161895616894571365.jpg plus some Aussie ones (lower right). I have "some" SRC's & Lemco's, not quite the values needed15462022424613673388999383072786.jpg
But what I'm after is the tubular ceramic, air gapped "dogbone" type15462025891691811088673747419330.jpg
These are 47pf as used between the phase inverter plate resistors (fizz cap) on the amp above.
Damn Sysco, now you've gone & put the JTM45 bug in my head for "after the next build". Cheers
 
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syscokid said:
Guess what? I'm confused again. I thought you are rebuilding a JTM45 clone. What type of Marshall are you rebuilding?
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No, no, I'm not rebuilding a Marshall. This was a rebuild of my 50 Watter with NOS components. Also am planning a '69 era 100 watt superlead build using NOS components, hopefully start building around February. This is what I require the 470pf ~ 560pf dogbone caps for. Sorry for the confusion. Cheers
 
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ivan H said:
No, no, I'm not rebuilding a Marshall. This was a rebuild of my 50 Watter with NOS components. Also am planning a '69 era 100 watt superlead build using NOS components, hopefully start building around February. This is what I require the 470pf ~ 560pf dogbone caps for. Sorry for the confusion. Cheers
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Dang nabbit... I meant to say: "What type of Marshall clone are you rebuilding?" Anyways, because your amp has a tube rectifier and JTM45 style power tranny, I assumed your amp is based on a JTM45 circuit.

Then when you are describing "470pf ~ 560pf dogbone caps", I'm confused again because up till now, I've never seen those vintage caps at those values in the shape of a dog bone. Smaller values, yes. Like a Lemco 47 pF fizz cap.
 
syscokid said:
Dang nabbit... I meant to say: "What type of Marshall clone are you rebuilding?" Anyways, because your amp has a tube rectifier and JTM45 style power tranny, I assumed your amp is based on a JTM45 circuit.

Then when you are describing "470pf ~ 560pf dogbone caps", I'm confused again because up till now, I've never seen those vintage caps at those values in the shape of a dog bone. Smaller values, yes. Like a Lemco 47 pF fizz cap.
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Sorry for the confusion Sysco. The amp is a EL34 50 watter that borrows from both a '67 & '68 spec. I used the JTM45 PT as it gives the same B+ as the 1202-113 PT that was used in some '67 & early '68 amps, some tube & some SS rectified.
The dogbone type caps came in a wide range of values, I've seen up to 2000pf (0.002uf). They can be seen used as treble & treble peaked caps in some late 12 series amps, '69 & '70s amps. They impart a grainy, gritty quality to the tone. Cheers
 
RVA said:
If you want to get them, I will get them to you, if need be.
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Thank you very much for the offer RVA, very much appreciated. I think I should keep focused on the upcoming 100 watt superlead though & not get sidetracked. I still have quite a bit to get for, including transformers, chassis & headcab etc. I may have a lead on two NOS period correct 470pf dogbones for, which will complete the circuit components. Cheers
 
It's those red doggy ones, huh?

Check out the bias control![/QUOTE]

Yes, those are the type I have a lead on two of, same as the 47pf types that are used between the phase inverter plates. That bias adjust pot looks pretty dodgy, doesn't it. Cheers
 
67plexi said:
Ivan where on earth did you find that board material
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The correct, fully perforated board material, both the darker kind used in earlier amps (like I have used) & the lighter coloured type used in the later ('69~'72) amps, turreted with the correct turrets can be obtained from Merren Audio. Cheers
 
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