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Has anyone made a Mouser bill of materials yet?

I'll up this.

Shannon

Shannon -

You might want to add the 1/2" aluminum spacers too, so there
are no surprises ... they are hard to source locally.

Also R-22 is shown as 7.5Kon the schematic and 10K on the BOM.

Will do!

Shannon

Oh... I also might source the power input (switch, fuse, and IEC if desired) from Mouser. I always liked those "Mountain" brand rocker switches.

Shannon, why do you suggest the 5408 (three amp) rectifier diode for this circuit? I can see using it in the heater supply, but for B+ duty I would have thought a fast recovery diode would have been preferred. Any comments?

No reason to not use the something like a UF4007. I made a couple mods from Tom's schematic which was a modded Bob's schematic, but tried to keep it as close as possible otherwise until I built one. So don't hesitate to change something.

Shannon

While I'm busy substituting parts, any thoughts on these swaps?

D3, D4 -> Schottky diodes 511-1N5821
C1, C2 -> Wima MKP10 polypropylene box caps 505-M10.22/400/5P
C3, C4 -> "Audio Grade" 16 volt, 330 uF 647-UKW1C331MPD
C5, C6 -> "Audio Grade" 100 volt, 100 uF 647-UKW2A101MPD
R3, R4, R13, R14 -> carbon composition 30BJ500-1.0K

I would have liked to have used the "exact match" for C3, C4 except it was backordered. I didn't think the 16 volt rating would hurt anything here, since I can't imagine the cathode voltage of the 12SL7 is going to be more than a couple volts above ground.

Those look fine, Ty. It looks like the dims of the caps will fit, though the lead spacing may be snug and not allow a flush mount. But not a problem in this design.

Shannon

The lead spacing ought to be the same as the ones in the recommended BOM. I checked the data sheets. It's 3.5mm spacing for the little guy, and 5mm for the bigger one. I think I'll go grab the board and a ruler and verify. The Wima cap has 22.5mm spacing, which I think will fit neatly into the innermost holes on the board.

No other comments on the use of the Schottky diodes for the voltage doubler in the heater supply? To be honest, I'm not sure I fully appreciate all the pros and cons. I just know they are used in the GetSetGo, so I figured they would be appropriate here.

Ty_Bower wrote:The lead spacing ought to be the same as the ones in the recommended BOM. I checked the data sheets. It's 3.5mm spacing for the little guy, and 5mm for the bigger one. I think I'll go grab the board and a ruler and verify. The Wima cap has 22.5mm spacing, which I think will fit neatly into the innermost holes on the board.

Ah - OK. I didn't back reference the lead spacing. Just eyeballed it with a board. That's cool then.

Ty_Bower wrote:No other comments on the use of the Schottky diodes for the voltage doubler in the heater supply? To be honest, I'm not sure I fully appreciate all the pros and cons. I just know they are used in the GetSetGo, so I figured they would be appropriate here.

The Schottky diodes were necessary in order to squeeze the CRC filter in there, otherwise we had too much voltage drop due to the standard diodes. I admit that I can't remember the exact process, but Schottkys were 100% necessary for the GSG (i.e. a standard inline bridge would've been easier).

For the Clementine doubler circuit, they aren't necessary. You would need to determine R26 at "run time" - may be 1 to 3 ohms. With the standard diodes, I think R26 will be a jumper most of the time.

Shannon

Question on the fuse (for the whole Darling Clementine) - is 1/2A, slow blow about right? I'm guessing 650mA @ 12.6V, plus 52mA @ 280V is less than 23VA, so the whole amp is less than 1/4 A draw from the line.

Ty_Bower wrote:Question on the fuse (for the whole Darling Clementine) - is 1/2A, slow blow about right? I'm guessing 650mA @ 12.6V, plus 52mA @ 280V is less than 23VA, so the whole amp is less than 1/4 A draw from the line.

I think that should fly. Just measured mine with a Kill A Watt:
0.24A, 29VA, 26W

Shannon