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Hi Folks, new poster here, I purchased an S111 V6 Mainboard and Transformer set from Stephen nearly one and a half years ago well i have finally put the amp together . I have one tiny little problem no sound nothing happening when plugging in a input lead, I do hear some quite audible hum when probing a few of the valve pins similar in sound to holding the hot tip of an input lead.
When I first fired the amp up it hummed like a freight train after shutting it down hopefully quick enough I checked the wiring and found i had wired the rotary impedance switch incorrectly with one of the impedance wires connected to the hot tip tab, hope i haven't damaged the O.T. Since built a light bulb limiter !

Voltage readings
B+ 357V

EZ 81
Pin 1- 310 V AC
Pin 3-370 V DC
Pin 7-307 V AC

V1
Pin 1-168 V
Pin 3-1.16 V
Pin 6-308 V
Pin 8-0 V

V2
Pin 1-173 V
Pin 3-1.5 V
Pin 6-311 V
Pin 8-0 V

V3
Pin 1-158 V
Pin 2-22.7 V
Pin 3-33.9 V
Pin 6-311 V
Pin 7-31.5
Pin 8-33.6 V

V4
Pin 3-304 V
Pin 7-354 V
Pin 9-351 V

Pin 3-304 V
Pin 7-345 V
Pin 9-350 V

I don't have a 6v6 voltage chart at the moment so i haven't done any readings on V7 and V8
Any advice on this matter would be more than appreciated .
I forgot to mention I'm running Russian 6p14p
EL- 84 equivalents .

check the ground connections to those cathode resistors.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Missing ground for sure

Or you forgot a wire going from cathode to board (or gain switch).

Without a ground there is no current draw. That is why your plate resistor is not dropping any voltage (no current flow) so your plate voltage is the same as the B+.

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http://pdfelectronics.com

Thanks guys for the quick response, over the last couple of days I re soldered all the grounds and checked all the wiring per the layout, I have edited the voltage list i posted.
Still no voltages on pin 8 of V1 and V2 now I'm getting way to high voltage [304 V] on pin 3 of V4 and V5, there is definitely some crazy rhythm going on with the voltages in the mean time I'll keep plodding and see if i can nut it out. An after thought i don't have the 220k resistors on the tube cathode switch may be that could be the problem.

No that won't be the problem

See if you can post some pictures of your build

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http://pdfelectronics.com

Ok I have triple checked the wiring, jumpers and grounding connections all checks out per layout I'm still not getting any voltages on V1 pin 8 and V2 pin 8 there doesn't seem to be much happening down that lower side of the board voltage wise , may be i have blown some resistors and caps.
When using the the multimeter probe on V3 I was getting very loud sound from the speaker similar to plugging a guitar in when the amp is turned on, my diagnostic ability's are nearly at an end i might have to pull the board out and start again.
I'm really looking forward to hearing this amp running I have redone the voltage chart some of the voltage have gone down while V1 pin 6 is extremely high . I have attached a few pics I'll try and take some better ones, some of the wire i used is not correctly colour codes as that was all had at the time . Thanks again for any help .

Voltage readings
B+ 347 V

EZ 81
Pin 1- 300 V AC
Pin 3-365 V DC
Pin 7-300 V AC

V1
Pin 1-158 V
Pin 3-1.2 V
Pin 6-277 V
Pin 8-0 V

V2
Pin 1-156 V
Pin 3-2 V
Pin 6-304 V
Pin 8-0 V

V3
Pin 1-149 V
Pin 2-2 V
Pin 3-33 V
Pin 6-281 V
Pin 7-22
Pin 8-33 V

V4
Pin 3-12 V
Pin 7-356 V
Pin 9-347 V

V5
Pin 3-12 V
Pin 7-350 V
Pin 9-347 V

Get a pic of the tubes and the boost switch

_________________
http://pdfelectronics.com

When i received the board i noticed it was different to the layout, the 100k resistor was soldered to the 16uf 450V cap with no jumper wire coming off the 100k going to the .022 sozo cap I have since moved it per layout the included pic i found on the forum should explain it more clearly .
Another thing i noticed was when probing the input jacks there was deadly silence .
I wasn't quite sure if you wanted close ups of the tubes kurtlives hope the pics are ok .

Sorry, I should have been more clear

Take a picture of the tube socket and the wiring around it

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http://pdfelectronics.com

Will do , I should have realised that my self

Good news the amp is going, I replaced the 12ax7's with another set, I found a blob of solder hidden between a couple of the valve socket pins looks like i have destroyed set of brand new valves while swapping them around from socket to socket .
On a positive note I have gained a little more knowledge on grounding , current flow, cathodes and general functioning of amps .

A few of the voltages on V3 are low , I'm running Russian 12ax7 equivalents on modified socket savers at the moment .

V3
Pin 2= 20 V should be 52V
Pin 3= 42 V " " 75V
Pin 6= 174 V " " 217V
Pin 7= 20 V " " " 62V
Pin 8= 42V " " " 75V

Thanks kurtlives for taking the time to try and sort out the problem .

That's good news. Dont sweat the low voltage too much if it sounds good. Tubes are not precise devices! No more than carbon comps, so there can be alot of variability.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Glad it's working

_________________
http://pdfelectronics.com

Thanks Guys, I'm really pleased with the amp , need to give it a good work out with the old Strat.

Looks great. Good job on the cabinets!

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps