Touchkeyer detail.
An excellent hunk of equipment from Sumner, WA1JOS. It uses the Jackson Harbor Press PK4 chip, apparently "proprietized" here by Sumner-san himself. As many other OPs have noted before me--this is about as much fun as a fella can get with a 20-dollar bill.
I'm quite new to PIC-based technology, so please bear with my pedestrian description: There are two of the 12F683 chips in this kit. Picture and datasheet here.
It would be really fun to get into PIC programming. I've noticed Bre Pettis doing it over on MakeMagazine.com and it's piqued my interest plenty.
Anyway, when I saw the tops of these chips "blackboxed" I instantly felt like I had to dig up the poop on these chips.
UPDATE: I received a comment on a popular QRP radio reflector in regard to these interestingly obfuscated chips from a prominent programmer ham in Prague: The chips are not PICs, but QT-113H. I have little doubts about it, even though
the touchkeyer seller insists it is a custom programmed PIC. I even asked him
directly and he repeats his truth. If it was a custom programmed PIC, then he
will not need to file out the chip label. I built mine with two SMD QT-113H
chips, that I bought from Farnell.
You did a fancy job, but the keyer is very insensitive, if you glue the
electrodes directly to the tin. You found it already by trial and error. The
capacitance of the electrodes against the tin is too high. It helps a lot to
elevate them. I placed a piece of plastic ruler between the electrodes and tin.
You could find more info on electrodes and sensitivity in QT-113H datasheet.
Fair enough. -Jonathan
Touchkeyer detail.
An excellent hunk of equipment from Sumner, WA1JOS. It uses the Jackson Harbor Press PK4 chip, apparently "proprietized" here by Sumner-san himself. As many other OPs have noted before me--this is about as much fun as a fella can get with a 20-dollar bill.
I'm quite new to PIC-based technology, so please bear with my pedestrian description: There are two of the 12F683 chips in this kit. Picture and datasheet here.
It would be really fun to get into PIC programming. I've noticed Bre Pettis doing it over on MakeMagazine.com and it's piqued my interest plenty.
Anyway, when I saw the tops of these chips "blackboxed" I instantly felt like I had to dig up the poop on these chips.
UPDATE: I received a comment on a popular QRP radio reflector in regard to these interestingly obfuscated chips from a prominent programmer ham in Prague: The chips are not PICs, but QT-113H. I have little doubts about it, even though
the touchkeyer seller insists it is a custom programmed PIC. I even asked him
directly and he repeats his truth. If it was a custom programmed PIC, then he
will not need to file out the chip label. I built mine with two SMD QT-113H
chips, that I bought from Farnell.
You did a fancy job, but the keyer is very insensitive, if you glue the
electrodes directly to the tin. You found it already by trial and error. The
capacitance of the electrodes against the tin is too high. It helps a lot to
elevate them. I placed a piece of plastic ruler between the electrodes and tin.
You could find more info on electrodes and sensitivity in QT-113H datasheet.
Fair enough. -Jonathan