Paul B
Well-known member
I gots a bunch, all 1/2 watt tho. Which do you have in mind?
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Help Support GroupDIY Audio Forum:
What are you using for R16? On the schematic, it shows 68k, color code wise, thats blu-gry-org if Im not color blind. It connects to your voltage line after the R29 47 k 2 watter.
OK, we are going to disable the side chain temporarily to see if that wacky ac stuff goes away.
there shpuld be a wire going to ther R34, R35 junction that feeds the AQ5, and this same wire will go also to R33, the 220k plate resistor on V3.
Dis connect the wire.
there shpuld be a wire going to ther R34, R35 junction that feeds the AQ5, and this same wire will go also to R33, the 220k plate resistor on V3.
Dis connect the wire.
Crap. Am I toolate!
Just pull the tubes, V3 and V4 out.
Doh on me.
Just pull the tubes, V3 and V4 out.
Doh on me.
Paul B
Well-known member
R16 is 68k. Pulled V3 and 4. even more whacko - a-837V. b- 754, c- 590 d- 718.
OK, pull V1.
Paul... how tidy would you say your wiring is? im just curious... is it nice and short wires with good routs and bends? or is it just kinda all over the place? im not questioning your workmanship but am wondering as I have had a few on the bench with oscillations due to some messy point to point...
Paul B
Well-known member
pulled V1. even worse: 848, 775, 764, 741
OK, pull the last tube and tell me what the neon bulb is doing.
Paul B
Well-known member
pulled last tube. neon is glowing. "volts" now 880, 870, 856, 834
OK, read dc on caps c7 a b c. d.
Paul B
Well-known member
I got 401, 397, 395, 387 VDC
OK, thats good.
Do you have any caps around like a 0.1 at 400dc?
If not, what is the voltage rating on C11, the cap on the AQ5 plate?
We want to shunt the "rf" to ground via the cap to see if you have some stuff on your dc voltage line or if it is just your meter acting funny.
If C11 is 300 or more, pullthe T4 module, and connect pin 3 of the T4 socket to ground via a jumper wire or whatever you have. Then re check for the weird ac readings.
Then measure your heater voltage to see if your meter is working on 6.3/12.6 ac.
Do you have any caps around like a 0.1 at 400dc?
If not, what is the voltage rating on C11, the cap on the AQ5 plate?
We want to shunt the "rf" to ground via the cap to see if you have some stuff on your dc voltage line or if it is just your meter acting funny.
If C11 is 300 or more, pullthe T4 module, and connect pin 3 of the T4 socket to ground via a jumper wire or whatever you have. Then re check for the weird ac readings.
Then measure your heater voltage to see if your meter is working on 6.3/12.6 ac.
Paul, do you have a 1 k and 100 k or so resistor? 1/4 ok.
If so, solder them together to form a voltage divider, clip each end across your heater wires (grn-grn) and measure the ac on the 1 k. This will tell you if your meter is funny, if it does not display millivolts, then we have solved the phantom ac mystery.
Trouble shooting test equipment is all part of the game.
If so, solder them together to form a voltage divider, clip each end across your heater wires (grn-grn) and measure the ac on the 1 k. This will tell you if your meter is funny, if it does not display millivolts, then we have solved the phantom ac mystery.
Trouble shooting test equipment is all part of the game.
Paul B
Well-known member
the voltage at c11 was "884AC" and 397 DC. pulled t4b and shorted pin 3. still getting the wacky readings at the c7 caps and was "876AC" and 401 DC at c11.
I am still getting no voltage ac (or dc) on the pin 3 side of c11.... I know you said you got 60 VAC on both sides with PR cranked. so this is way off.
I am still getting no voltage ac (or dc) on the pin 3 side of c11.... I know you said you got 60 VAC on both sides with PR cranked. so this is way off.
Paul B
Well-known member
oh, and on the heater wires 3.4VAC individually to ground and 7.1 on both greens together.
no, thats ok, don't worry about c11.
lets clear the meter thing up
can you find a pair of resistors that are 1/50th or 1/100th the value of each other? does not have to be exact.
see if you have a 1 k or 10 k and we can go from there.
that high ac volts would fry those caps in a second, so i know it's not real. I just want to show you that the meter is not really reading ac, but millivolts ac, but not telling you.
lets clear the meter thing up
can you find a pair of resistors that are 1/50th or 1/100th the value of each other? does not have to be exact.
see if you have a 1 k or 10 k and we can go from there.
that high ac volts would fry those caps in a second, so i know it's not real. I just want to show you that the meter is not really reading ac, but millivolts ac, but not telling you.
Paul B
Well-known member
I have a 1k and 100k, do I solder them in series or parallel? _ think you mean series, and then just measure on both sides of the 1K?
exactly, series.
then unplug unit, tack them across heater greens with lite solder, hook up across 1 k resistor...and should read 63 without a millivolts reading.
then from here on in, its a piece of cake, clear sailing, duck soup, cream of wheat, made in the shade with cool-ade.
can you dig where i'm coming from?
can you relate to my trip, man?
how many freaks are there in the world?
then unplug unit, tack them across heater greens with lite solder, hook up across 1 k resistor...and should read 63 without a millivolts reading.
then from here on in, its a piece of cake, clear sailing, duck soup, cream of wheat, made in the shade with cool-ade.
can you dig where i'm coming from?
can you relate to my trip, man?
how many freaks are there in the world?
