Led not lit and no output sound.

[Hilts]

Wire removed from pin 8. Paul do you mean check the resistance between A3 and terminal 3 or do a DC voltage check at A3 ?

[Paul Birkeland]

Resistance.

[Hilts]

Resistance is still 420 Ohms

[Paul Birkeland]

I would replace the 9 pin socket and the LEDs (since they probably won't come off without being damaged).  There's likely debris inside the socket giving partial continuity between pins 4 and 3 causing this problem.

[Hilts]

What actually is the function do the led's. Is it just to light up the valve? Would it affect the sound at all as to me the amp sounds amazing.

[Paul Birkeland]

The LEDs provide the correct bias voltage for the 12AU7 which also influences the operation of the 6080.  Your amp currently isn't working and shouldn't be used until this issue is remedied.

[Hilts]

Would it be possible to source the 9 pin socket and led's from the UK?

[Paul Birkeland]

Would it be possible to source the 9 pin socket and led's from the UK?

https://www.mouser.co.uk/ProductDetail/Broadcom-Avago/HLMP-6000?qs=sGAEpiMZZMt82OzCyDsLFG14VY5EtHXv%2FT3fszwBz5E%3D

https://www.hotroxuk.com/9-pinb-9-pin-miniature-valve-socket.html

Mouser is plenty reliable, but I can't vouch for the socket supplier.

[Hilts]

Thanks Paul. Will get these ordered and see if it sorts the problem.
I my just try and replace the led first and see if that works.

[Paul Birkeland]

I my just try and replace the led first and see if that works.

If you remove the LED connected to A3, does the resistance value there change?

[Deluk]

I bought 4 of these "just in case" as I know mine don't have any slack in the leads. One was loose but re soldered OK and I have had no problems since.
https://www.ebay.co.uk/itm/133944214342?epid=648834726&hash=item1f2fb28346:g:dhIAAOSwBxFhnhO7

Amazon.uk have sockets.

[Hilts]

If you remove the LED connected to A3, does the resistance value there change?

Right Paul. I've removed the LED from A3 and the resistance between A3 and terminal 3 goes to O/L which is the same as A8.

I also tried the battery tip that Drew1D mentioned on another LED thread.

"I would take like a AA battery, and clip or tape a wire to each side of it.  Now, with those two wires, touch the positive side (the nipple side) to the pin of the socket, and the negative side to the center of the socket, did it light up?  Do the same to the other LED"

A3 LED would not light up but A8 did light up.

Does this mean the LED is knackered?

[Paul Birkeland]

You can install a jumper between A3 and A8 to restore operation to the amp till you obtain a replacement LED. 

[Hilts]

I forgot to mention that the wire is still not connected to pin 8 on the power transformer and the 12AU7 valve is not in.

Is the 9 pin socket lickly to be OK and it's just the LED that's not working?

I will order another LED first.

[Paul Birkeland]

Nothing you've done will cause the 12AU7 not to light up.  You can put the wire back on pin 8 of the power transformer if you'd like.

If the 12AU7 doesn't glow but the 6080 does, you have a loose wire at B7, B8, or A9 (maybe more than one of those terminals).