R3 and R103 of 2K2 seem very high to me. Looking at the Philips datasheet for the ECC83 and the "Resistance-coupled amplifiers" chapter in the RCA Receiving Tube Manuals, I would think 680 to 820 Ohm is a more normal value.
But it would surprise me if this would explain you hearing nothing at all. And I don't see anything else in the schematic that is wrong.
But it would surprise me if this would explain you hearing nothing at all. And I don't see anything else in the schematic that is wrong.
PCL200, don't forget that there are R14 and R114 basically in parallel with R3 and R103 accordingly in terms of DC
Than forget about what I wrote about R3 and R103 because like TG pointed out, for DC you wind up close to 1K1 as the total resistance for DC.
Instead of questioning the schematic why not start with basic troubleshooting? What are the voltages in the unit compared to the schematic?
check to make sure that the center tap of the power transformer secondary HV winding is grounded.
Even if the balance in the phase splitter is not good, the amplifier would still give sound (even if the lower EL84 would get zero input signal). But TS wrote that there's no sound at all.
If the center tap of the secondary of the power transformer would not be grounded, than there would not be any B+, or? But TS wrote that he has B+.
If the center tap of the secondary of the power transformer would not be grounded, than there would not be any B+, or? But TS wrote that he has B+.
Do you hear anything at all from your speaker? Hum or other noise?
Measure the voltages of the EL84 at the plate (pin 7), cathode (pin 3), and grid (pin 2) with respect to ground.
Double check that your output transformer is wired correctly.
Measure the voltages of the EL84 at the plate (pin 7), cathode (pin 3), and grid (pin 2) with respect to ground.
Double check that your output transformer is wired correctly.
from the top EL84
tube 1
pin 7 318V
pin 3 5V
pin 2 0V
tube 2
pin 7 322V
pin 3 0V
pin 2 0V
tube 3
pin 7 322V
pin 3 0V
pin 2 0V
tube 4
pin 7 322V
pin 3 0V
pin 2 0V
tube 1
pin 7 318V
pin 3 5V
pin 2 0V
tube 2
pin 7 322V
pin 3 0V
pin 2 0V
tube 3
pin 7 322V
pin 3 0V
pin 2 0V
tube 4
pin 7 322V
pin 3 0V
pin 2 0V
Hard to make sense of those figures, the schematic has no voltages on which doesn't help. When you build something it's a good idea to check and re-check your work by eye, it's very easy to make mistakes, have you used the right resistor value's? it's easy to mix up a 10k and 1k resistor for instance.
Second, back to basics, are the valves glowing? The heaters on ECC83's are on pins 4/5 & 9, pins 4 & 5 are tied together for 6v operation, there should be 6.3v AC between them. Heaters are on pins 4&5 for an EL34.When counting pins on valves, pin 1 is the first after the cap on the left hand side bottom,looking at the valve base from the bottom, gap at the bottom. Count clockwise for pin 2 etc.
Second when i take voltages I write something like this for an ECC valve-
V1 a
g
k
h
a
g
k
h
You should have 6.3v AC between pins 4/5 & 9, there should be something like 100-200v on pins one and 6 - anodes, there should be 0v on pins 2 & 7 grids and lastly there should be about 1.1v on pins 3 & 8 cathodes.
On the EL84's there should be 0v pin 2, about 10/11v on pin 3, 6.3v between pins 4&5, about 300v on pin 7 & 9.
It's a good idea to remove the negative feedback connection on a first power up, this is C6/R14 from the cathodes of the ECC83's.
Lastly if you have no sound from either channel that means there is something wrong common to both channels.
Good luck, Andy.
Second, back to basics, are the valves glowing? The heaters on ECC83's are on pins 4/5 & 9, pins 4 & 5 are tied together for 6v operation, there should be 6.3v AC between them. Heaters are on pins 4&5 for an EL34.When counting pins on valves, pin 1 is the first after the cap on the left hand side bottom,looking at the valve base from the bottom, gap at the bottom. Count clockwise for pin 2 etc.
Second when i take voltages I write something like this for an ECC valve-
V1 a
g
k
h
a
g
k
h
You should have 6.3v AC between pins 4/5 & 9, there should be something like 100-200v on pins one and 6 - anodes, there should be 0v on pins 2 & 7 grids and lastly there should be about 1.1v on pins 3 & 8 cathodes.
On the EL84's there should be 0v pin 2, about 10/11v on pin 3, 6.3v between pins 4&5, about 300v on pin 7 & 9.
It's a good idea to remove the negative feedback connection on a first power up, this is C6/R14 from the cathodes of the ECC83's.
Lastly if you have no sound from either channel that means there is something wrong common to both channels.
Good luck, Andy.
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Ok. Tube 1 is functioning. The other tubes don't appear to be.
Unplug the amp and measure the resistance from pin 3 to ground for each tube. The resistance should be that of the 270 ohm resistor. Also, make sure that each electrolytic capacitor at the cathode is installed correctly with (+) connected to cathode and (-) to ground.
Unplug the amp and measure the resistance from pin 3 to ground for each tube. The resistance should be that of the 270 ohm resistor. Also, make sure that each electrolytic capacitor at the cathode is installed correctly with (+) connected to cathode and (-) to ground.