COULD TUBES BE FLATTEN OR BAD OR SOMETHING ELSE?

[Slam Dunk]

I HAVE PURCHASED A AMPLIFIER THAT USES 2 813 TUBES. WHEN I TURNED THE AMP ON IT SHOWED 349 MILLIAMPRES I HAVE A SMALL RM KL 500 THAT I AM USING DEAD KEY SET AT 50 WATTS. WHEN TRYING TO TUNE THE AMP AND LOAD IT AT FIRST IT SEEMED TO BE GOING OK AT LEAST I THOUGHT. THE WATT METER READS 50 WATTS FROM MY SMALL DRIVING AMP AND WHEN I PUSH THE FOOT PEDAL I HEAR THE BOX CLICK LIKE IT ENGAGES BUT TUNE AND LOAD ONLY MOVES JUST ABOUT 10 TO 20 MORE WATTS BEFORE IT
RETRACTS TO A LOW READING. I HAVE TRIED AGAIN AND AGAIN BUT IT DOES THE SAME THING AND WHEN I LOOKED THROUGH THE LITTLE HOLES IN
THE SIDE BY THE TUBES THEY ARENT EVEN GLOWING AT ALL NOT RED NOT BLUE NOT NOTHING. THERE IS AN EXPLANATION FOR THIS EITHER I'VE BEEN
HAD BY A PERSON THATS ADVERTISING ON THE WEB "THE BEST AMP I HAVE
EVER OWNED" AND PUSHING CRAP OFF ON SOMEONE ELSE OR THE TUBES ARE NO GOOD BUT THEY DONT LIGHT UP AT ALL WHEN THE KEY IS DOWN. SOMEONE TELL ME THAT I JUST NEED SOMEMORE TUBES OR THIS PROBLEM IS NOTHING SERIOUS. OH THIS AMP IS A WELL PUT TOGETHER HOMEMADE I GUESS WITH B&W PARTS. HELP!:angry:

Please kill the CAPS LOCK key.

I have constructed a few '813 boxes, one was control grid driven with separate positive screens volts and negative going voltage bias supply. Most "Homebrew 813 amps were grounded grid and just like an 500Z it required 30 -50 watts drive per tube to light those graphite plates..

Take the bottom off and get a picture, diagram of how the tube is wired and what's in the bottom of the amp. It can be figured out from there what kind of amp it is.

Filaments don't light and possibly no B+ on the tubes; get pictures.

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[HiDef]

Some 813s have square plates that look like tantalum. Audio enthusiasts gobble these up. The graphite plate ones can handle more abuse.

Plate dissipation was rated lower than other tubes with similar sized plate structures. Look at an 810 same size plate which is rated at 175 watts diss. Filament wattage to plate dissipation ratio is high. That means plenty of emission reserve. These work much better than tubes like the 572B which has a lot of rated plate dissipation for the filament wattage.

Real life 600 watts P.E.P. out of a pair for good tube life. They will do much more for a short time. AM about 150 watts carrier out for a pair IF there is air on the tubes. Pulsed radar CB schwing audio who knows.

Cathode driven zero bias at about 2000 volts. Zener bias above that.