Anyone Build Lite III?

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wayneosidas

Anyone Build Lite III?

Post by wayneosidas »

Curious about the C/R spec/values.

thanks
wayne
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markh
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Post by markh »

I'm still working on it. I have the tagboard done, and most of the parts. Now all I need is some free time!

--mark
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wayneosidas

Post by wayneosidas »

Hey Mark,
Its your schem/layout correct? I noticed there are a few variances between the two, one of which being the diff PI and Preamp tubes. Ill be using the 12ax7s and went ahead and ordered the C/R's off the layout from mouser, may need a little tweaking of values, any thoughts?

thanks
wayne
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markh
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Post by markh »

Where *is* the layout? The schematic values are mostly right, I think I shifted the PI values to the Voxish values on the layout.

--mark
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wayneosidas

Post by wayneosidas »

Mark heres the Layout: -Igot this off the yahoo site-
http://groups.yahoo.com/group/18watt/fi ... s/Lite.gif

and here is the schem i crossed it with: -off the current site-
http://mhuss.com/18watt/schematics/Lite3.gif

There are a few value changes between the 2 but nothing major, i got a bench amp w/the same tube compliment and PT/OT characteristics that will be ez to pop the circuit into. I liked you circuit cuz it looks pretty straight forward and simple, maybe I can play around w/switchable SS/Tube recto and ad trem down the line.

any thoughts?
thanks
wayne
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markh
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Post by markh »

Oh yeah, that old Yahoo group. :P :mrgreen:

That layout is correct, but some of the values are stale. The schematic is correct on the left side (I tuned the tone resistors around the volume control, and doubled the cathode bypass to 2.2), but my current build has the 1.2k / 47k cathode string and 1M grid resistors. I'll try to post updates for both (and maybe a pic or two) this weekend.

-mark
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wayneosidas

Post by wayneosidas »

Right on mark

I ordered a few extra cathode values as i dont know how my PT is gonna behave w/the draw of the extra tube, the old amp is using ez81/12ax7/2x6gw8, I beleive the 6gw8's pull more than the el84's so Im hoping it will balance out. The PT has only one heater filament and looks to be physically on the small side.

Anyway, that would be great if you could post a little more info!

thanks
wayne
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