Please help with my first build 5F1 with no sound

[tubeswell]

The dropping resistors are the 10k and 22k resistors (if your's measure at 9.96k - that's close enough to 10k, and 21.7k is close-enough to 22k).

Check you have the correct value plate resistors for the 12AX7. They should be 100kOhm each. The 12AX7 stages both might be pulling too much current maybe (if the plate resistors are wrong), and this could pull the pre-amp supply down

[überfuzz]

The heater wire doesnt look the same in the layout....

Aren't the tubes glowing?

[icy_wind500]

yes they are

[icy_wind500]

I've tried to make it as close as possible without losing focus

[tubeswell]

Hard to tell what's going on behind the board. Do some continuity checks with your r-meter. The following should all read 0

The 6V6 grid (pin 5) to the junction of the 220k and the 0.022uF.

The 12AX7 input grid (pin 2) connected to the junction of the 2 x 68k.

The 12AX7 2nd grid (pin 7) connected to the pot wiper (This is a shielded cable, but you may've inadvertently shorted the cable core to the cable shield at one of the cable ends)

The 12AX7 2nd cathode (pin 8) connected to the junction of the 22k and 1k5.

The 25uF, 470R, 220k junction connected to the ground side of the 10uF pre-amp filter cap.

The 1st two filter cap grounds (the 10uf and the 22uF) connected together.

[icy_wind500]

I've checked all those connections are good !

[tubeswell]

Apart from the low voltages, I'm still wondering whether the shielded cable from Pin 7 of the 12AX7 to the vol pot is shorted to the cable shield. If Pin 7 to ground reads zero ohms with the pot maxed, I suspect it may be.

Regarding the low voltages, another possibility is that you may have a partially-shorted or improperly grounded filter cap (one of the 10uF caps). Have you got a spare 10uF or 22uF filter cap that you can tack in parallel with one of the 10uFs (one 10uF at a time) to see?

Did you check that the plate resistors for the 12AX7 (the ones going to the .022uF/plate socket pins (1 and 6) junctions) were 100k each?

The other things is - are you triply sure you have the 6V6 grid (Pin 5) going to the junction of the 220k/.022uF? (and not to the 220k/470R/25uF?), and are you positive you have the 220k/470R/25uF going to the 10uF pre-amp filter cap ground (and not to the 220k/.022uF junction)?

[icy_wind500]

Apart from the low voltages, I'm still wondering whether the shielded cable from Pin 7 of the 12AX7 to the vol pot is shorted to the cable shield. If Pin 7 to ground reads zero ohms with the pot maxed, I suspect it may be.

Regarding the low voltages, another possibility is that you may have a partially-shorted or improperly grounded filter cap (one of the 10uF caps). Have you got a spare 10uF or 22uF filter cap that you can tack in parallel with one of the 10uFs (one 10uF at a time) to see?

Did you check that the plate resistors for the 12AX7 (the ones going to the .022uF/plate socket pins (1 and 6) junctions) were 100k each?

I will try to use a normal wire to see if it is the shield,
I dont have any spare caps because this is my first build
Those resistors are 101.9 and 108.1

[tubeswell]

When you measure the resistance between Pin 5 of the 6v6 to the 220k/.022uF junction, what reading does the R-meter give?

[icy_wind500]

It gives 0.04

and I've tried a normal wire still no sound

[tubeswell]

When you put the R-meter between the 10uF pre-amp filter cap ground and the 470R/25uF/220k junction, what is the resistance reading?

[icy_wind500]

When you put the R-meter between the 10uF pre-amp filter cap ground and the 470R/25uF/220k junction, what is the resistance reading?

0.8ohms for both 10uF caps

[tubeswell]

Put your meter on the 'VAC' setting and measure between pins 2 and 7 of the 6V6. What is the VAC reading?

[icy_wind500]

Put your meter on the 'VAC' setting and measure between pins 2 and 7 of the 6V6. What is the VAC reading?

0.542V Or do I need to plug it in and turn it on ?
oh its now 0....

[icy_wind500]

0.542V Or do I need to plug it in and turn it on ?
oh its now 0....

stupid me, its 6.77

as the tubes warms up, its now 6.80