Rockwell666 wrote:wow what a beautiful build!
What value of trim pot did you use for the bottom of the CF? lastly are the 220K resistors off v7's plates tied to the grids? its hard to tell in the drawn schematic.
Im using a different circuit for the LTPI and CF and I want to try this setup out.
Sorry, just seeing this. I used mhartman's layout and tweaked from there, not the hand drawn scheme. But the 220Ks come off the cathode of the driver tube, and are fed with the bias voltage. 25K for the trimmer, and that is for the plates of the LTPI, not the CF
For what it's worth, the owner just called and said the amp(1yr old) was whistling and whining when turned up. I had him replace the driver tube and that did the trick, and gave him more volume and headroom apparently. Just a reminder that a poor 12ax7 takes a beating in that position.
Smokebreak wrote: ↑Sat Aug 22, 2015 7:14 pm
I did the low filter, and realized that I was 1 lug position off on the whole thing for the high filter So I'll need to do that one again.
Here's the low filter. I omitted the 39K.
I think I'm building something between a JM an a #002. I schematicized mhartman's layout(nice work!!) and it's very similar to what I drew out, so I'll lean on that layout for sure. I've got about 12 pieces of paper in front of me, so that should get me something good !
Does anybody know what the part number is for this switch? The alpha switch I bought based on a part number floating around here doesn't have the extra solder tabs to mount the other side of the caps, they are cut off. I know this is 6 position but I can figure out how to buy the 7 position one if I have the part number for this one.
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Krinkle wrote: ↑Sun May 07, 2017 11:46 pm
Does anybody know what the part number is for this switch? The alpha switch I bought based on a part number floating around here doesn't have the extra solder tabs to mount the other side of the caps, they are cut off. I know this is 6 position but I can figure out how to buy the 7 position one if I have the part number for this one.
From page one of the datasheet:
SR=Rotory
25=Diameter (1")
1=Number of Sections (Layers or Wafers)
1=Wiring Type Terminals
01=Number of Poles
07=Number of Positions
Blah, blah, blah...
So it should be wire terminals.
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"Education is what you're left with after you have forgotten what you have learned" - Enzo
Sorry, I'm probably not being clear about what I'm asking. I have the same switch in your pic.
But take a look at the pic I posted. See how your switch has only 8 terminals, the one in the pic I posted has extra terminals, the other side (common side) of the caps are each connected to these extra terminals on the opposite side of the switch and it makes it easier and neater to wire/solder the caps onto the switch.
I think is the same 7 pole filter you have but with 2 layers instead of 1, although it should make no difference. Maybe you should follow Hartman's wiring diagram from the layout?
So I'll need to do that one again.
