The above circuit IS NOT for commercial use. Its free to be copied for personal DIY use. Any other use needs my permission Aug 31, 2008
But there is nothing in it not already covered by prior art.🙂
But there is nothing in it not already covered by prior art.🙂
Here is my L adapter in a small edition for my filaments feed tube vs Lm317 CCS.
Big improvements in sound more bass and more details realy
Big improvements certify the very good waveform on my scope against waveform of the lm317...
Big improvements in sound more bass and more details realy
Big improvements certify the very good waveform on my scope against waveform of the lm317...
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Very good news.
For those wanting an upgrade of heaters PSU vs the LM317 one in the original 6V6 line preamp's schematic here's the L-Adapter circuit. Its a general purpose high current PSU that can be set from very low to about 20V. But three red LEDs and the trimmer without setting jumpers are enough in this 6.3V heaters fixed voltage case. For more information, that PSU's thread link is: L-Adapter
For those wanting an upgrade of heaters PSU vs the LM317 one in the original 6V6 line preamp's schematic here's the L-Adapter circuit. Its a general purpose high current PSU that can be set from very low to about 20V. But three red LEDs and the trimmer without setting jumpers are enough in this 6.3V heaters fixed voltage case. For more information, that PSU's thread link is: L-Adapter
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Joined 2009
Paid Member
Just dropped in - interesting thread, but did I understand this correctly, you get an improvement in sound by changing one regulated DC supply for another regulated supply for the heater on an indirectly heated valve ? is the heater power transformer separate from the B+ power transformer ?
Improvements are like what happens when we wash our car. Mine always runs better! I bet yours does too.🙂
All done without red LEDs. Does the color matter?😀
All done without red LEDs. Does the color matter?😀
I dont have any other separate transformer..... All in one...
Before with Lm317 as current limit....
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Filament wire is jam packed in the cathode cylinder. If there is noise on it, can couple to the cathode.
😉I
A test may persuade you with L-Adapter..
It is not a matter of red led, as much as the quality of liquid detergent.😏
A test may persuade you with L-Adapter..
It is not a matter of red led, as much as the quality of liquid detergent.😏
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Joined 2009
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Agreed, there can be noise but the subjective results included improved bass and I don't see how that occurs unless it's a) the treble is better which funny enough can result in the bass seeming better even if it's unchanged, b) the heater supply being on the same transformer as B+ has some influence on the plate supply other than coupling rectifier noise.
I never wash my car. It's a sliver colour car, the same colour as dirt 😀
Don't know about the subjectives, he did the listening, I picked the mentioned better scope result thought. The 317 chip CCS supply was high impedance, the new one is voltage source i.e. low impedance, maybe there was interference pick up beyond the new one has less self noise.
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Joined 2009
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This is a wild theory but strong bass may mean strong current pulses through the tube which depletes slightly the electron cloud around the cathode and with better cathode heating the result is improved behaviour when it demands strong current pulses ?
He may enlighten us bit more about the scope thing. Was it some amount of fuzz vs a good DC line or merely a thicker DC line vs a thinner DC line?
Hi
Τhe waveform I got with my scoppe on LM317 CCS was amount of fuzz vs very good DC line of L-adapter not a simple thicker DC line vs a thinner DC line...
Τhe waveform I got with my scoppe on LM317 CCS was amount of fuzz vs very good DC line of L-adapter not a simple thicker DC line vs a thinner DC line...
It is time to put my hand on this simple version.
Nothing special here, just to try things.
I have so many used 6v6 so why not.
No good looking but playing nicely.
Good work Salas, very good!
The power supply!
A generic power supply that I picked up from the trash!
Nothing special here, just to try things.
I have so many used 6v6 so why not.
No good looking but playing nicely.
Good work Salas, very good!
The power supply!
A generic power supply that I picked up from the trash!
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Good luck and keep us posted if you will go further like boxing it up. ΜΠΑΚΑΚΟΣ TP-4 HV Bench PSU! I did not know there was an old time electronics branding by that iconic Athenian pharmacy firm. It looks like they had been selling some local OEM HV PSUs for chemical work.
An externally hosted image should be here but it was not working when we last tested it.
Yes indeed, I found this in the trash outside a microbiological laboratory.
Old days instruments.
What first come in mind was to salvage the analog meters but final i prefer to keep as h.v power supply.
Old days instruments.
What first come in mind was to salvage the analog meters but final i prefer to keep as h.v power supply.
O.T.
Any of the Hellenic friends could explain me why in the past all the signs were Farmakeion, Estiatorion, etc. and now Farmakeio, Estiatorio without the final "n"?
This puzzle me every time I see an old Greek pic.
Thanks
End of O.T.
Any of the Hellenic friends could explain me why in the past all the signs were Farmakeion, Estiatorion, etc. and now Farmakeio, Estiatorio without the final "n"?
This puzzle me every time I see an old Greek pic.
Thanks
End of O.T.
A scholar version of the language was used by the state, much literature, newspapers, for over one hundred and fifty years. It had very many classic elements as it was something between the ancient and the modern common language. It faded enough until officially abandoned in the seventies.