Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: lvrocker on April 28, 2018, 07:23:33 pm

Title: Stout TMB voltages
Post by: lvrocker on April 28, 2018, 07:23:33 pm

Hi all, finished up the wiring on what is my second ever build...still learning... so the Stout powered on (yay) and am starting to test some voltages on the 5y3 and right off I'm getting 440 vdc on pin 8 also board connections a, b, c and d....absolutely no voltage drop at all after each filter cap. Connections seem fine, I'm using a classic tone marshall 18 watt power transformer rated 290-0-290. Curious as to why these readings are so high? FWIT pins 4 & 6 are 325 vac which I believe are fine. Thanks for any help!

Title: Re: Stout TMB voltages
Post by: BruceF on April 28, 2018, 07:28:57 pm

Are the tubes installed?

Title: Re: Stout TMB voltages
Post by: lvrocker on April 28, 2018, 08:11:21 pm

just the rectifier as of now

Title: Re: Stout TMB voltages
Post by: PRR on April 28, 2018, 08:53:43 pm

You need a load to get a voltage drop.

Now that you have proved "not dead", give it some work to do. Install tubes.

Title: Re: Stout TMB voltages
Post by: lvrocker on April 29, 2018, 01:24:01 pm

yep, installing tubes brought things more to normal voltages. I'll have to remember that...thanks guys

Title: Re: Stout TMB voltages
Post by: BruceF on April 30, 2018, 04:12:54 am

Cool.  Glad to hear no problems.