Original Dynaco ST-70 has low voltage readings everywhere?

I guess the quad cap could be bad but it is brand new. All my voltages are roughly 1/2 what they should be. I do NOT have one of the 240V power transformers (as I do not see any violet/white or violet/black wires on the power transformer.

i disconnected the power transformer completely and all the voltages were fine...but when reassembled....all low.

Also the Quad cap is new. ALL the electrolytic caps are new. the 2 x .02mfd ceramic cap is just barely out of spec (about 25% low, spec is +/- 20%)

what am I missing?

So... here are videos of measuring voltage on the Dynaco ST-70. I have tried to check everywhere for a short or bad connection. I disconnected everything to the "can" cap and it read just fine standing all alone (= to another new one) all the parts of the power supply are new OR have been tested independently out of circuit. All electrolytic caps are new. Here is a video as well and here  

cant seem to load a picture but I can share it....go to this link https://www.dropbox.com/s/t0renobbsga6mtu/20210311_164804.jpg?dl=0  and see an overall and two "blowups" of each 1/2 of the power supply area. the link will open the overall image. hit the "back" arrow and you'll get to the folder with all three images.

Good morning mchavez.....

I have just now seen your post and your photos.

From what I can see in your photos the first thing I would do is there are a lot of cold solder joints everywhere in the amp. I would heat up a soldering iron grab a roll of good rosin solder and refresh every solder connection in the amp first that may fix the low voltage problem. If not then check every tube especially the rectifier tube and make sure the tubes are seated good in their sockets.

looked just about anywhere...no issues there, also just for fun tired two other rectifier tubes.....no difference

Are you able to set bias?

the voltages are still about 2/3 of the installation instructions...AND... during past attempts I could not get the amp to Bias...but today....NO problem the EL-34s are all matched the same so technically the bias should have been exactly the same. and one needed a little more than the other but both sides are working .....BUT I bet the voltages are still low.   I'm super happy the amp plays but i want to understand why the low voltage.

That is quite the conundrum. So many things it could be. When you measured the secondaries disconnected were they all disconnected at the same time and measure or did you measure one at a time disconnected? When did the issue start or what was the last change before it started?

I measured all the secondaries disconnected from everything....I had thought that the main transformer was bad....but as all of the number were on target (vis a vis the installation instructions, I felt sure the main was OK.

PS after I set the bias last night I've been playing music thru it all day. seems to be working fine

Have you measured the voltages again since you set the bias? One thing I have noticed is if bias is not set properly on my VTA ST-70 the voltages are all out of whack but on the high side because not enough current to drawn down the voltage to the proper levels. Still could be something on one leg of the secondaries or something on the mains or maybe something on the board. Polarity should not be an issue but is the hot going to the fuse then switch then mains?

OK FULL STOP.   the problem seems to be in my current limiter.  When I tested my known working amp, I did it with the amp plugged into the wall. All voltages were fine. Today I tried the new amp on a regular household circuit...and voila! power levels all just fine!!!

I had tested the power supply and current limiter weeks earlier with my DVM and all voltages read just fine BUT the volt meter does not have any feedback (probably wrong term)  into the circuit. The tube amps all leave a dull glow on the bulb which a volt meter does not do. the bulb is a 150 watt bulb.  I believe this is the problem.

I now have the "new" amp playing and all biased correctly. I will keep using it for a week or so....whew! I was going crazy.

SORRY  to put you all thru the diagnostic wringer but since I had tested the current limiter with the DVM and tested the power transformer thru the same circuit, I figured I had eliminated that as an issue.

What did I do wrong when building the current limiter? I will have to investigate.  

Glad you found it. It helps to have another set of eyes and ears to bounce things off of during troubleshooting.