• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Base of the tube slightly loose

I bought a tube of this: https://www.amazon.com/dp/B000FKF80M?psc=1&ref=ppx_yo2ov_dt_b_product_details
Going to try a syringe on a couple not so valuable tubes. My biggest fear would be that some adhesives maybe conductive.
Even slightly would be a big problem. Good luck with your mission.

It seems to be a siliconic compound, I already tried it and had not good results. As for the conductivity, once dried there are only polymeric -n(Si-O-Si) bonds so there shouldn't be a problem (no ionic bonds inside).
 
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Oh PLEASE!!!!!!
There are many forgotten cures like this. Leaks in a heating boiler? Throw in a lump of fresh horse manure. The fibrous texture fills cracks and the other matter cooks and seals. In car cooling systems, oatmeal is effective. Our Army has suggested eggs.
https://heatinghelp.com/dead-men-tales/dead-men-tips
http://www.mtfca.com/discus/messages/80257/108041.html?1254283672
Army Battle Damage Assessment and Repair: Egg to stop a Radiator Leak video
 
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All straight from😉
Richard-Saunders.jpg


😉 😉
 
Old thread i know, but why start new one.
I have been having fun swapping output tubes on se tube amp. It has 6sn7 front, and i was mostly using kt88 on output. Small 5 watt edcor ot.
Just for fun i measured distortion at various power supply voltages. I just used variac before my normal hv power supply and adjusted between 180 to 300 volts. Here are some results, some surprising for me.
 
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Most surprising is that 6L6 have lowest distortion, offcourse draw less heater current, and with increasing hv power supply, distortion goes down to sweet spot. And it sounds great too. Well, they all sound good, but 6L6 fits to this little tube amp.
 

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I have replaced CRC with CRCRCRC and noise went down a little. There is more voltage drop, so my power supply does not reach 300Vdc now, but its ok.
So i remeasured 6L6 output tube, from 140V to 240V. As expected, distortion goes down with increasing the voltage.
The noise goes still little bit up, overlay attached. Not sure why. At minus 84dB its not a problem.
 

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