#002 - my journey begins

[Bombacaototal]

Just thought I'd add a diary on the progress of my #002. Chassis are still getting powder coated and then will go to silkscreening, so I think progress will be slow. Using the lovely boards by Erwin, PCB do make life much easier. I have populated parts of the boards, still awaiting on some components.

[talbany]

Just thought I'd add a diary on the progress of my #002. Chassis are still getting powder coated and then will go to silkscreening, so I think progress will be slow. Using the lovely boards by Erwin, PCB do make life much easier. I have populated parts of the boards, still awaiting on some components.

Cool!
Make sure you check the values on those old TVA.s
They have been known to drift wildly out if they have been sitting a while. Ask me how I know this

Best of Luck!
Tony

[Bombacaototal]

Just thought I'd add a diary on the progress of my #002. Chassis are still getting powder coated and then will go to silkscreening, so I think progress will be slow. Using the lovely boards by Erwin, PCB do make life much easier. I have populated parts of the boards, still awaiting on some components.

Cool!
Make sure you check the values on those old TVA.s
They have been known to drift wildly out if they have been sitting a while. Ask me how I know this

Best of Luck!
Tony

Thanks Tony, invaluable tip, and yes I am measuring everything, resistors too. I'd say the piher (specially larger values like 1M, 2.2M) 6PS and TVA have a large drift but I used ones within range unless deliberately going for out of range

[Bombacaototal]

I have been reasearching for a number of days on the treble cap, 360pF of #002 (attached). It clearly is not a MICA, must be ceramic, but I have not seen any ceramic in such a dark red colour. Any ideas of what manufaturer this may have been from?

[rootz]

Cera-mite? The contrast is very high in the picture, so all darker mid tones look like shadows. Look at those Piher resistors, they also look a bit darker than you’d expect.

[erwin_ve]

I have been reasearching for a number of days on the treble cap, 360pF of #002 (attached). It clearly is not a MICA, must be ceramic, but I have not seen any ceramic in such a dark red colour. Any ideas of what manufaturer this may have been from?

How did you come to that conclusion it's not a silver mica?
I have several old and new ones: they are all over the place in terms of size, shape and color.

[Bombacaototal]

I have been reasearching for a number of days on the treble cap, 360pF of #002 (attached). It clearly is not a MICA, must be ceramic, but I have not seen any ceramic in such a dark red colour. Any ideas of what manufaturer this may have been from?

How did you come to that conclusion it's not a silver mica?
I have several old and new ones: they are all over the place in terms of size, shape and color.

Thanks for the reply, I have never seen a round silver mica, only ceramic caps, hence my conclusion. So you presume this is a round silver mica? I will search for some old ones in a similar shape..

[erwin_ve]

I have been reasearching for a number of days on the treble cap, 360pF of #002 (attached). It clearly is not a MICA, must be ceramic, but I have not seen any ceramic in such a dark red colour. Any ideas of what manufaturer this may have been from?

How did you come to that conclusion it's not a silver mica?
I have several old and new ones: they are all over the place in terms of size, shape and color.

Thanks for the reply, I have never seen a round silver mica, only ceramic caps, hence my conclusion. So you presume this is a round silver mica? I will search for some old ones in a similar shape..

I know from other pics of SSS where the sm cap is bent towards the board. This might give the impression its round. But honestly I cant tell from this pic really.

[Bombacaototal]

Some small progress

[Bombacaototal]

Amps is ready, but I am having a weird issue. Normally it's fairly quiet, but sometimes there is a fair bit of hiss introduced. In such situations, where the hiss is present, if I turn the volume to zero I cannot hear it, which indicates there is an issue in the stack or in the first triode of the tube. I have replaced the tube to 4 different ones, and the issue of the hiss being present sometimes is regardless of the tube. What I noticed is that if I tap the layout board with a stick, the hiss is gone, and will only come back if I tap the board again or move the amp. I thought it could be a cold joint or something so I re soldered all of them but unfortunately with same results. Any clue of what may be happening? Or any thing potentially checking

[erwin_ve]

Cold solderjoint on the connections to the tube pins?

[Richard1001]

Cold solderjoint on the connections to the tube pins?

Yes, on the cathode wire of V1A, there seems to be no solder at all. Also check the other sockets.

[Bombacaototal]

Thanks Erwin and Richard, must be a cold joint then, let me go through all connections again

Well noticed Richard, I had originally soldered all from the back, as the PCB lugs are fairly small and my parts are somewhat large, so I thought it was a good approach, but I have since re done from the top too

Erwin, which power tubes are you using. I have the TAD 6l6 wgc, but found the amp super super bright with lacking of bottom end. And I have done the filter entrance correction

[erwin_ve]

Thanks Erwin and Richard, must be a cold joint then, let me go through all connections again

Well noticed Richard, I had originally soldered all from the back, as the PCB lugs are fairly small and my parts are somewhat large, so I thought it was a good approach, but I have since re done from the top too

Erwin, which power tubes are you using. I have the TAD 6l6 wgc, but found the amp super super bright with lacking of bottom end. And I have done the filter entrance correction

Power tubes are also TAD: 6L6GC-Str blackplate rca style.
You mid accent is also off?(near master)
Lnfb at v1 is 100k resistor?

[Bombacaototal]

Thanks Erwin, yes 100k, and my mid is changed to the presence cap, and it's off

Also I have a ground loop with the suggested grounding scheme. Anyone else had this?