found RCA tone control manual
and a Crowhurst article
looks like even I can do that
btw, consider its a 2channel/stereo
using one channel for bass, and one channel for mid/top
enables the two channels to be configured differently
like using the trick with a small bypass cap on cathode resistor, to achieve a little more high frequency gain
and having seperate attenuator for each channel further enhances sound balance control
and a Crowhurst article
looks like even I can do that
btw, consider its a 2channel/stereo
using one channel for bass, and one channel for mid/top
enables the two channels to be configured differently
like using the trick with a small bypass cap on cathode resistor, to achieve a little more high frequency gain
and having seperate attenuator for each channel further enhances sound balance control
not sure why the cathodes are bootstrapped
ah, ok
by bootstrapping, the input/gain tube would achieve a bit more gain
guitar amp builders say it gives more 'grunt'
well, no real need for that here
bootstrapping the cathode output tube gives higher impedance load
and that might be of advantage, considering the EQ curcuit
well, I dont know this, but it seems logical
hope its beginning to look better
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needs a bit 'refinement'........
works better, smoother and much faster now
I think it will be a good tool
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and this is the way I plan to use it
seems like I will have to do some cuts for soldering directly to the ground plane, or else it takes too much heat
hmm, solder pads appears to be a bit big for some smaller components like multiturn pots with smaller legs
might have to use bigger pots
or try to build a smaller tool
well, I might take the challenge
seems like I will have to do some cuts for soldering directly to the ground plane, or else it takes too much heat
hmm, solder pads appears to be a bit big for some smaller components like multiturn pots with smaller legs
might have to use bigger pots
or try to build a smaller tool
well, I might take the challenge
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hmm, solder pads appears to be a bit big for some smaller components like multiturn pots with smaller legs
its close, but looks like that will work too
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Why not just build it on plain matrix board?.
I dont have any
only ordinary boards
old pieces, bought long time ago
why waste them
anyway, you dont find it good to have a 'free' ground plane ?
but ofcourse you are right, matrix board would be easier
anyway, you dont find it good to have a 'free' ground plane ?
If you were building an RF device, perhaps so - but for a low quality valve audio unit it doesn't matter.
Old tobacco tins are great for building things in ....
I have plenty of these small boxes
look for modems, digital receivers, etc
metal and not plastic, ofcourse
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I have plenty of these small boxes
look for modems, digital receivers, etc
metal and not plastic, ofcourse
But presumably you can't solder to them?.
But presumably you can't solder to them?.
I could weld
I could weld
But rough on the transistors though
But they are very nice looking boxes.
not long ago I found an old B&O receiver
it gave me a nice trafo
but I also took the frontplate with me
I felt stupid, but just thought it looked nice, and might be of use, somehow
hacking off the right piece, and voila
it gave me a nice trafo
but I also took the frontplate with me
I felt stupid, but just thought it looked nice, and might be of use, somehow
hacking off the right piece, and voila
Attachments
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