I designed this little PCB for those killer alpha pots you can get from Jaycar.
I have not tried it yet.
Mostly I wanted the board to avoid having to solder wire directly to the tiny pot, but also because I wanted a place for a resistor on input since for even some of my unity gain headphone amps some of my soures are too hot.
Cheers!
Russ
I have not tried it yet.
Mostly I wanted the board to avoid having to solder wire directly to the tiny pot, but also because I wanted a place for a resistor on input since for even some of my unity gain headphone amps some of my soures are too hot.
Cheers!
Russ
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BrianDonegan said:Can you change it to have input and output jumpers, rather than left and right jumpers? Oh, and some mounting holes?
Looks good. Thanks.
Absofreakinglutely.
needlz said:Are you using the double ganged pot for the input or 2 singles?
????
This is a double ganged pot yes.
They are 10K double gang logs:
https://secure4.vivid-design.com.au...d1=&Keyword2=&pageNumber=&priceMin=&priceMax=
https://secure4.vivid-design.com.au...d1=&Keyword2=&pageNumber=&priceMin=&priceMax=
needlz said:Right... sorry... I thought you were using an alpha double ganged log pot but all I see on jaycar is the double linears.
Its not problem, I just didn't understand the question.
Cheers!
Here is an update:
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What about tightening up the layout a bit and adding mounting holes?
And we should start updating the wiki more, it seems a little out of date.
Is there a diyaudio ftp somewhere for linking to stuff on the wiki? or should we link to the forums? I would use my host, but in 5 years you'll just see 404 not found errors.
And we should start updating the wiki more, it seems a little out of date.
Is there a diyaudio ftp somewhere for linking to stuff on the wiki? or should we link to the forums? I would use my host, but in 5 years you'll just see 404 not found errors.
asgorath said:What about tightening up the layout a bit and adding mounting holes?
And we should start updating the wiki more, it seems a little out of date.
Is there a diyaudio ftp somewhere for linking to stuff on the wiki? or should we link to the forums? I would use my host, but in 5 years you'll just see 404 not found errors.
Mounting holes?
Seriously? Hadn't considered it. The PCB is just an extension of the pot. And its tiny.
BrianDonegan said:They are 10K double gang logs:
https://secure4.vivid-design.com.au...d1=&Keyword2=&pageNumber=&priceMin=&priceMax=
Ahh... didn't click on page 2 of the results.
thanks.
I was thinking of mounting the pot at the back of the amp and using a long rod to connect it to the knob. That way my inputs are nice and short and far away from the transformer. Mounting holes would make this a lot easier. Though, I could always just add extra board space for the mounting holes without it actually being part of the copper.
BrianDonegan said:I was thinking of mounting the pot at the back of the amp and using a long rod to connect it to the knob. That way my inputs are nice and short and far away from the transformer. Mounting holes would make this a lot easier. Though, I could always just add extra board space for the mounting holes without it actually being part of the copper.
Ahhh good thinking, well I hadn't planned on using like that, but I will create a second board with mounting holes.
Hi Brian you and Russ are definitely Jammin’…
I hope this is not out of context but wondering if you still think that the touch sensor QProx was still a unique idea, worth developing.
http://www.qprox.com/products/qtouch.php
I hope this is not out of context but wondering if you still think that the touch sensor QProx was still a unique idea, worth developing.
http://www.qprox.com/products/qtouch.php
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I do. The circuit is so simple. Using it to switch a power relay is super simple. De-bouncing isn;t a problem, and the toggle state is build in. I have a working test circuit for this. It consists of one chip ($.98each), a 10nF cap, a pull-down resistor and a relay.
Now, what I need is the logic circuitry for source switching. My last Digital Logic class was in 1989 or there abouts, so I am a little rusty. I plan on using the chips in pulse mode (emits a logic low pulse), one chip per source, but need the logic to turn on the source replay and release the other relays. I keep meaning to sit down and thinkit through but can't find the time. If anyone wants to pitch in, I will design and etch boards for it and get the whole thing tested. I bought 5 of the 110 chips with my last digikey order.
Now, what I need is the logic circuitry for source switching. My last Digital Logic class was in 1989 or there abouts, so I am a little rusty. I plan on using the chips in pulse mode (emits a logic low pulse), one chip per source, but need the logic to turn on the source replay and release the other relays. I keep meaning to sit down and thinkit through but can't find the time. If anyone wants to pitch in, I will design and etch boards for it and get the whole thing tested. I bought 5 of the 110 chips with my last digikey order.
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