Valve Itch all resistors 1/4W except: R2 & R10?
PSU Itch all resistor 1/4W except: R1 & R4?
Cool
I experimented with Silver Micas, PIO, Polystyrene & Tin Foil and now Teflon FT-1 on the 15nF placement and they all produce very different perspectives.
I hope I could get the Teflon definiton and extension with the Tin Foil/styrene presence and tone coherence, added with a little bit of SM snap
Hi All,
attached is the BOM for the itch. It covers the valve itch circuit + the PS schematic shown above, i.e. heaters, basic HV but leaves out the actual shunt components.
The BOM is an excel type workbook. This first worksheet is the main BOM with links to mouser parts. The other worksheets show the schematics to match the BOM and a SSHV schematic with values to suit the itch current and voltage requirements is included. I have also included a PDF in case someone has no way of reading an excel file.
Purely selfishly, I have only done mouser parts as that's who I normally order this kind of stuff from. If someone would like to add digikey and farnell references as well, that would be fantastic. Likewise alternate ebay sellers for the other stuff too.
Now the disclaimer!! The BOM has been examined by 3 sets of eyes, mine, Salas and Merlin el Mago - BUT that's not to say there isn't some mistake in there, or indeed that a better choice could be made. So please keep your eyes open and minds active when doing your order!!!
Please let us know here if you do find something wrong - it may save hassle for others coming after you.
Fran
attached is the BOM for the itch. It covers the valve itch circuit + the PS schematic shown above, i.e. heaters, basic HV but leaves out the actual shunt components.
The BOM is an excel type workbook. This first worksheet is the main BOM with links to mouser parts. The other worksheets show the schematics to match the BOM and a SSHV schematic with values to suit the itch current and voltage requirements is included. I have also included a PDF in case someone has no way of reading an excel file.
Purely selfishly, I have only done mouser parts as that's who I normally order this kind of stuff from. If someone would like to add digikey and farnell references as well, that would be fantastic. Likewise alternate ebay sellers for the other stuff too.
Now the disclaimer!! The BOM has been examined by 3 sets of eyes, mine, Salas and Merlin el Mago - BUT that's not to say there isn't some mistake in there, or indeed that a better choice could be made. So please keep your eyes open and minds active when doing your order!!!
Please let us know here if you do find something wrong - it may save hassle for others coming after you.
Fran
Another proposal. I know people may want to try different capacitors for the RIAA section, and you may have your own ideas about what you want. But most will agree that there should be good matching between L&R channels. There are 2 caps involved, 15nf and 47nf.
If prospective builders could get together, it should be possible to get either the seller to match pairs or buy a surplus amount and match them...... There's probably only 3 or 4 people here right now who are building or near building.... but it might be enough. If you could find a russian ebayer with all of the types of caps needed, they might do a deal for a 2% matched pairs of 47nf and 15nf and non-matched sets of the other caps needed for everything else for a single shipping price.
Just suggesting it!
Fran
If prospective builders could get together, it should be possible to get either the seller to match pairs or buy a surplus amount and match them...... There's probably only 3 or 4 people here right now who are building or near building.... but it might be enough. If you could find a russian ebayer with all of the types of caps needed, they might do a deal for a 2% matched pairs of 47nf and 15nf and non-matched sets of the other caps needed for everything else for a single shipping price.
Just suggesting it!
Fran
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That might be a very good idea... I am testing the FT-1 for the 15n placement with outstanding results but all values I got are 15.7n and higher. I wish I could have some 15.1nF and 15.3nF to test.
I do not know if any of the russian suppliers is dependable enough to do such a matching but I will ask.
There is another (American) supplier that also provides Teflon caps... Merlin... Can you help ?
I do not know if any of the russian suppliers is dependable enough to do such a matching but I will ask.
There is another (American) supplier that also provides Teflon caps... Merlin... Can you help ?
Ricardo, ask Marko matched pairs (shop 33Audio).
Site: Surplus USA Film Capacitors Teflon Polycarbonate Polyester Polypropylene
E-mail: marko@33audio.com
15$00 USD each
Cheers,
Felipe
Site: Surplus USA Film Capacitors Teflon Polycarbonate Polyester Polypropylene
E-mail: marko@33audio.com
15$00 USD each
Cheers,
Felipe
Sorry you are right
, I forgot HV for Itch RIAA, but for 15nF Marko has 0.015uF 10% tol. 400V, TexCap 200GGS.
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