Hi Tyler - welcome to the forum!
nugent.tyler wrote:
I got through my Brit45 build and ran into a snag. Step 9 of the testing procedure tells me to turn the amp on in standby and measure the voltage on the red terminal of the 32uF cap. I read 0V between the chassis and this lug when the amp is in standby.
This is actually a mistake in the instructions. The red terminal of the 32uf cap is located after the standby switch, so if the the amp is in standby mode, there will not be any voltage present at that location.
nugent.tyler wrote:
I went ahead and proceeded with testing and here are my results when standby is off - installed all tubes and the plates are glowing. Note, when I put the amp back in standby the voltage on the 32uF cap's red terminal drops back down.
A: Expected 450VDC @ Red 32u - Measured 0VDC on Standby, 448V Standby Off
B: Expected 440VDC @ Yellow 32u - Measured 460VDC
C: Expected 380VDC @ Red 16u - Measured 461VDC
D: Expected 310VDC @ 16uF on board - Measured 465VDC
Note that C and D are reading high.
This doesn't seem possible. The highest DC voltage in the amp should be at pin 8 of the rectifier tube, which connects to point A when the amp is not in standby. You should not be able to get any higher voltage after that point. Pin 8 feeds the B+, then the voltage should drop a little after the choke at point B, then lower after the 8.2k resistor at point C, and then lower after the 10k resistor at point D.
Is this with the power tubes installed? Are you sure you measured DC and not AC voltage? Are you measuring at the correct point? Is the black lead of your probe grounded?
nugent.tyler wrote:
When I get to step 18 I read 0V between pin 1/8 from either power tube and the chassis and no sound from the speakers (not even a pop coming out of standby).
Is your meter reading the right voltage range (DC millivolts)?
Photos can often help with troubleshooting. Please post clean, well lit photos of your build.