On 18 Watt TW Liverpool Power Stack

[kryfcn]

I would suggest to pull all of the tubes out and give us the voltages of the power tube sockets. Of particular interest is the voltage present on the #2 pins (bias voltage). This should be negative relative to the chassis.

If you can list the voltages by the pins it would be helpful. Remember, with EL84s, there is usually nothing on the unused pins 1, 6 and 8.

I agree with Pete that the HT on your power tubes seems wrong and the fact that your light bulb limiter is burning bright are an indicator that something is grounded that shouldn't be. Do realize that many amps will slightly flash the bulb on startup and should then fade to little to no light at all within seconds.

Can you post the schematic that you are working from. If it is not correct, we can get that sorted and perhaps find the correct layout as well.

Is this a kit? If so, model number? And any pics of your build in its current state may help a bunch.

Edit: my phone was not showing me Phil's posts. He is spit on in his comments. Sorry Phil.

Thanks for the very helpful reply. im going to share with you my voltages asap.
Koray

[kryfcn]

They layout for the liverpool will work just fine, the only difference I see is the power section having 2 less tubes and 2 less components (don't need dual 220uF cathode caps and 130R cathode resistors, just one to tie the two together).

The linked schematic to the 18W is different by quite a few components from the original, so that's up to you if you want to keep the preamp identical to Ken's version or follow the other schematic linked above. I didn't note everything, but a few simple examples of differences I saw:

1MA pot for Bass instead of 250kb, 50pF/100pF bright cap options instead of 100pF/500pF and I did note a 33k grid stopper instead of a 820R to 2.2k for the original, etc.

I kinda stopped there realizing someone had taken the liberty on that build to change it quite a bit from Ken's original designs.

SO up to you as to what you're shooting for.

~Phil

Thanks Phil .

[kryfcn]

Ok guys thanks for your helpful advises , i will write down all of my voltage readings without tubes here asap. Cheers.

[pompeiisneaks]

No worries. If that's the case, you can post in one, and ask if people thing it should be elsewhere and if needed it can easily be moved by me.

~Phil

[kryfcn]

Without power and preamp tubes voltages on rectification tap is : 445 vac .
On El84 pin 9: 442vac pin 7 : 445 vac .
I Used Ceriatone’s Power layout, and rest Ron Worley’s.

[dorrisant]

EL84 pin #2 voltage?

[kryfcn]

EL84 pin #2 voltage?

There is no Dc voltage without tube. Shows me 0.235dc both tubes is that normal?

[kryfcn]

Hello guys again. I’ve been working on power section of this project since 2 weeks. It finally sounds fantastic to me. But.. ive got a humming problem. Ive checked all of the filter caps and B+4-+5 components. Didnt help to eliminate. Source is where ? I dont really know. Sounds like 60cycle hum. When the volume is around 8-9-10 , it goes away. After when Standby switch on , it starts, a little bit reducing after few seconds . I swapped all the tubes. Tried everything by my side to get rid of it. Didnt help chopsticking cables or changing components. Thanks for help.