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).
Its been working great all day. After 24h setting time, greay goo looked like little rubber belt. Not too noticeable. Rock solid. Good for 550degC. My tubes barely make 100. All good. I think I should treat the other one in the pair, just to make it exactly the same looking.
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.Oh PLEASE!!!!!!
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
Yup... You can also fix a leaking gas tank by rubbing a bar of soap on it and detail the headlights with bug spray 😛
https://www.motorbiscuit.com/5-car-hacks-use-household-items-to-repair-your-vehicle/
https://www.motorbiscuit.com/5-car-hacks-use-household-items-to-repair-your-vehicle/
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.
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.
Last edited:
Nice measurements.
What surprises me is that the noise goes up with higher B+.
What would be the cause?
Edit - why is that IMD so high? That doesn't make a lot of sense.
Jan
What surprises me is that the noise goes up with higher B+.
What would be the cause?
Edit - why is that IMD so high? That doesn't make a lot of sense.
Jan
Last edited:
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.
Attachments
Not sure, i need to work on my power supply. Probably needs more filtration caps. Minus 75dB is not ideal i know.Nice measurements.
What surprises me is that the noise goes up with higher B+.
What would be the cause?
Jan
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.
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.
Attachments
Imd is relatively low itself. Imd + noise is high.Nice measurements.
What surprises me is that the noise goes up with higher B+.
What would be the cause?
Edit - why is that IMD so high? That doesn't make a lot of sense.
Jan
I have used 2-part epoxy for that with good resultsHi tube friends. I got question. Have been playing simple kt88 se amp, great sound, having fun swapping various kt88 brands. However, i noticed one tube is slightly loose between the glass and base.
Any remedy?
Isn't the IMD measurement FFT based?Imd is relatively low itself. Imd + noise is high.
Jan
No idea how RightMark measures it. But there are two imd + noise, one looks reasonable, other does not.
- Home
- Amplifiers
- Tubes / Valves
- Base of the tube slightly loose