That's the answer I was looking for and expected.any other repair guy would probably just pick a random component and fix it.
I did the matching different.
First i installed matched 10r at jfets, then measured the voltage developed over each resistor, with a 6.5 digit meter, i saw small variation in voltages, and since my 10r resistors are 1 percent and i have hundreds, i cherry picked resistors so that each resistor developed same voltage.
Hope i makes sense.
First i installed matched 10r at jfets, then measured the voltage developed over each resistor, with a 6.5 digit meter, i saw small variation in voltages, and since my 10r resistors are 1 percent and i have hundreds, i cherry picked resistors so that each resistor developed same voltage.
Hope i makes sense.
There is one listed in the build guide as used by the author, but I am not quite certain that it's the cable shown in the photographs.Hello. I am stuck at the umbilical wire gauge and cable model. I can t find a suitable mogami cable,
There is also another Mogami, and a Canare cable listed in the build document.
I personally wouldn't give it much thought unless I was intending what I'd consider a VERY long run.26awg. is that sufficient? thanks
I used a umbilical cable for use with car and trailer, 1mm2 and 7 cables, full dual mono, did i mention cheap?
Ohms law still applies, even for dig high end diy, 120 miliamps.
Ps, wanted screened cable but had to buy alot, impedance is ridiculous low so who cares about 1.5 meters.
Ohms law still applies, even for dig high end diy, 120 miliamps.
Ps, wanted screened cable but had to buy alot, impedance is ridiculous low so who cares about 1.5 meters.
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I love the concept of "overkill", but that is serious overkill, considering that each channel draws lessI used a umbilical cable for use with car and trailer, 1mm2
than 150mA. 😎
@amplidude @Boydk In order to match the channels, would it not be preferable to measure the betas of the transistors at their operating points, and vary the resistors to shift the operating points around to achieve similar operating betas?
From amazon.com: 10 meters long, 4 conductors, 20-AWG, price USD 16.99: link . . . . . This is NOT a recommendation, just an observation. Make your own decision and live with the consequences.
They also sell a similar cable with 24-AWG inside, for less money. And, intriguigingly, a 6 conductor version. With six conductors you could run three protective-earth wires for extra safety, AND the 6 pin connectors won't plug into anything else in your listening room. Your kids / au pair / in-laws / drunken guests can't plug any other cables into those 6 pin jacks.
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They also sell a similar cable with 24-AWG inside, for less money. And, intriguigingly, a 6 conductor version. With six conductors you could run three protective-earth wires for extra safety, AND the 6 pin connectors won't plug into anything else in your listening room. Your kids / au pair / in-laws / drunken guests can't plug any other cables into those 6 pin jacks.
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That´s why you have "Curve Tracing". Similar/matched transistors need similar/matched resistors to draw similar current, versus@amplidude @Boydk In order to match the channels, would it not be preferable to measure the betas of the transistors at their operating points, and vary the resistors to shift the operating points around to achieve similar operating betas?
vaired resistors, cause transistors are not equal/matched 😉
For my project i used two octect af matched jfets from punkydawgs, then i matched theese together myself once more.
I used my agilent 6.5 meter with pc software, did less measurement of of, meter did 15000 readings after 1 minute warm up ,and the i used the average as guideline
I used my agilent 6.5 meter with pc software, did less measurement of of, meter did 15000 readings after 1 minute warm up ,and the i used the average as guideline
Hmm... I asked earlier but it got lost.
Can you get pre matched component sets from a commercial source?
How difficult would be to implement "servo circuits" to handle fine tune matching? I guess it should be limited to audio frequencies only. I guess it would be limited to voltage level adjustments... do electronically adjustable impedance ( not pots ) circuits exist?
Could that be implemented in the quad set FE for the P3?
I was thinking of self biasing tube amps.
Can you get pre matched component sets from a commercial source?
How difficult would be to implement "servo circuits" to handle fine tune matching? I guess it should be limited to audio frequencies only. I guess it would be limited to voltage level adjustments... do electronically adjustable impedance ( not pots ) circuits exist?
Could that be implemented in the quad set FE for the P3?
I was thinking of self biasing tube amps.
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Probably not. But you can buy 0,01% resistors. 1% cap´s are the lowest I know of. Semiconductors, I guess you´ll have toCan you get pre matched component sets from a commercial source?
trust varoious sellers, that sells pairs/quads/octets.
To your other Q´s......... Someone might know more than me.
What is the calculation for gain, in db? I see some sketches on the schematic but I can't quite read them.
BTW, that site for punkydawgs on eBay is interesting. Is there a notion to have a sticky page somewhere with links to those vendors... mostly as a service, not a recommendation?
BTW, that site for punkydawgs on eBay is interesting. Is there a notion to have a sticky page somewhere with links to those vendors... mostly as a service, not a recommendation?
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