WIP
Always loved the UTC iron. Here's a W-20 all on one chassis.
And yes this is a "Boat Anchor Build"
Included is the Heyboer version of the UTC LS-74 power supply.
Rated at 275ma 400 & 385 plate. 5vac @ 6A. and 6.3vac @ 5A.
I included a pic of what an OEM W-20 looked like.
And Quad 1614 schematic.
The switch on top toggles the meter between the 1614 pairs.
The switch on the front right is a selector switch to choose 16 or 8 ohm outputs.
The switch on the left is power and gain.
Always loved the UTC iron. Here's a W-20 all on one chassis.
And yes this is a "Boat Anchor Build"
Included is the Heyboer version of the UTC LS-74 power supply.
Rated at 275ma 400 & 385 plate. 5vac @ 6A. and 6.3vac @ 5A.
I included a pic of what an OEM W-20 looked like.
And Quad 1614 schematic.
The switch on top toggles the meter between the 1614 pairs.
The switch on the front right is a selector switch to choose 16 or 8 ohm outputs.
The switch on the left is power and gain.
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Nice looking single-chassis version! Did you just finish it?
It looks like you have included a preamp tube, and as you say a 'gain' pot.
I guess you had to bring all the output transformer secondaries over and back from the rear left to the front right selector switch?
Did you add any extra protection for the power supply, given it has parallel 5U4, and all bypass caps would reach peak B+ before the signal tubes start loading their supplies ?
Did you come across the instruction manual for the W-20? That would be great to see, as I've only come across a W-10 manual.
It looks like you have included a preamp tube, and as you say a 'gain' pot.
I guess you had to bring all the output transformer secondaries over and back from the rear left to the front right selector switch?
Did you add any extra protection for the power supply, given it has parallel 5U4, and all bypass caps would reach peak B+ before the signal tubes start loading their supplies ?
Did you come across the instruction manual for the W-20? That would be great to see, as I've only come across a W-10 manual.
"I guess you had to bring all the output transformer secondaries over and back from the rear left to the front right selector switch?"
The way the LS-60A is set up, only had to bring out three wires to the selector switch. Also the selector switch controls feedback resistance, 4800 to 6800 ohms.
The power supply caps were beefed up considerably. Two oil filled 30uf caps.
The way the LS-60A is set up, only had to bring out three wires to the selector switch. Also the selector switch controls feedback resistance, 4800 to 6800 ohms.
The power supply caps were beefed up considerably. Two oil filled 30uf caps.
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