My new build ,high volyage readings

[danman]

Try to set it for the lowest AC voltage scale. It may be 20vac or something similar. You will get the best accuracy by using the lowest possible scale. If the meter is a newer Fluke then it may be auto-ranging and will set itself to the proper scale.

[fixer2]

No this is a older one around 1983 it is model et 77 I am tring to look up a manuel for it ,but it does hag label 300mv/dc could this be the sale to use ?

[danman]

Filaments are AC voltage so you should use the lowest AC voltage scale that will allow you to read at least 6-7vac.

[danman]

Make sure that the battery in the meter is good also or you will get false readings.

[fixer2]

Here is what I got now that I change the battery V1 pin 9 to 4/5 I get 6.34 volts on V2 pin 9 to 4/5I get 6.35 volts on V 4 pin 7 to pin 2 I get 6.44 volts

[fixer2]

I also have been re reading and going threw like I am building it again and why and how does the in put jacks work you got a resistor going from the ground the sleeve of the guitar cord to the hot side the tip then going to the V1,the why part is why doesnt this just groung out the single and go no where .

[fixer2]

I wish I could find some very close pictures of these area from other people that built tube depot builds because of there changes to the stock way ( tube depot design I mean when I say there changes )

[danman]

The 1m resistor soldered directly to the input jack is called the input resistor. It sets the impedance for the first stage and is necessary for proper operation. The signal does not ground out because 1m is a very high resistance and the signal voltage will want to take the path of least resistance. It continues on through the 68k resistors and then hits the grid of v1. Marshall style jacks have switching contacts that open and close depending on whether the cable is plugged in or not. They can also be a little tricky to wire up the first time and it helps to have a very clear diagram of the connections. If you want to understand more about how these type of jacks operate, I would do a Google search for "how do Marshall input jacks work".

If you are measuring the heater voltage at the preamp tubes with one lead on pin 9 and the other lead on pins 4/5, you should be seeing 12.6vac or very close. If this is how you measured and you only got 6.34vac then you have made a mistake in the filament wiring somewhere.

[fixer2]

Ok thanks for telling me how the input jacks works that does make sense. I will actually trace the wires of the heaters and see what nt do or say .Will get back with a new measurements.

[fixer2]

Hi This is what I did now . I un did the two heater wires coming from the transformer to the board and un did the polit light too.Safetly turn it on and measured red leed on one wire from the trans ,and the black leed on the chassis.I got a reading of 3.48 volts, on the other wire same way testing I got 3.49 volts.Then I put red leed on the one wire and the black leed on the other wire and got a reading of 7.0 volts. Do I have the right transformer ?????

[danman]

Yep, that voltage reading is correct. As far as the right transformer, you would have to check with the kit supplier to be sure of that.

[danman]

While you are at it, check to be sure that the tube rectifier is receiving the correct 5vac on the filament.

[fixer2]

Ok here are the readings I got on the rectifier tube .I re connected the transformer wires to the board and the polit light too. On pin number 2 red leed and the black leed on pin number 8, I got 2.25 volts. On pin number 8 red leed and the black leed on the chassis .5 volts On pin number 2 red leed and the black leed on the chassis I got , 7.96 volts . These three measurements were done in stand by mode. In play mode pin number 2 red leed and the black leed on the chassis ,I got 4.11 volts

[danman]

Without being there and seeing how you took the measurements, it's hard to say for sure. I believe that you have correct filament voltage. Does the rectifier tube light up when you turn on the amp? Pins 2 and 8 carry the AC filament voltage but pin 8 will also carry the high voltage DC that the rectifier produces. Pins 4 and 6 are where the two leads from the transformer's secondary connect and will read AC voltage. With the amp on, and in standby mode, what DC voltage do you read at pin 8 on the rectifier?

[fixer2]

Hi Ok I put the black leed on the chassis , and the red leed on pin number 8 and I got 467 dc volts in stand by mode and in play mode I got 474 dc volts.Yes the heater light does light up too