Author Topic: Is this Timmy Schematic correct?  (Read 549 times)

suryabeep

Is this Timmy Schematic correct?
« on: March 17, 2018, 12:19:35 PM »
Hi everyone,
I built a few timmy boards but none seem to work. I'm using this schematic

Is this scheme correct? (Biasing resistors, polarity diodes etc not shown here but are working correctly on the boards)
Still in the process of learning, so bear with me if I ask dumb questions :P

Kipper4

Re: Is this Timmy Schematic correct?
« Reply #1 on: March 17, 2018, 12:41:19 PM »
Voltages are ?
Jellybean dodging since 2012.
Smoke me a Kipper. I'll be back for breakfast.

electrosonic

Re: Is this Timmy Schematic correct?
« Reply #2 on: March 17, 2018, 12:46:54 PM »
You have swapped the input pins on the ICs

Andrew.

287m

Re: Is this Timmy Schematic correct?
« Reply #3 on: March 17, 2018, 12:48:15 PM »
^^
yeah. And minus vref : 8K2 (9v to vref) and 10K + 47u (to ground)

suryabeep

Re: Is this Timmy Schematic correct?
« Reply #4 on: March 17, 2018, 02:34:29 PM »
oof that explains it. Three different boards later and it's a dumb error ofc. I wish there was a facepalm icon in here somewhere.   :-[
Thank you guys! Could I simply 'fix' the issue by making a little conversion board that 'swaps' the pins around on the IC itself?
edit: tried just that, works like a charm!
« Last Edit: March 17, 2018, 06:22:59 PM by suryabeep »
Still in the process of learning, so bear with me if I ask dumb questions :P

PaulC

Re: Is this Timmy Schematic correct?
« Reply #5 on: May 01, 2018, 12:24:58 AM »
I just saw this post from last month, but I can't see the schematic to confirm.  There have been a few tweaks over the years I could give you to get it up to date if they're not in the posted schematic.

PaulC
I like ham, and jam, and spam alot

thermionix

Re: Is this Timmy Schematic correct?
« Reply #6 on: May 01, 2018, 01:28:05 AM »
^ Well that's awfully cool, ain't it?
FDH

duck_arse

Re: Is this Timmy Schematic correct?
« Reply #7 on: May 01, 2018, 11:09:11 AM »


don't ask me how I got that url right .....
winter. booo.

PaulC

Re: Is this Timmy Schematic correct?
« Reply #8 on: May 02, 2018, 12:51:31 AM »
That's pretty close, but it doesn't show what tapers to use for the pots.  The gain, bass, vol should be audio taper.  The treble is linear.  If you want to flip to the rotation of the tone controls use a reverse audio for the bass and switch the outside lugs of the Treble.  For several years now I've used a 25ka for the volume with an 18k resistor from input to wiper.  This alters the taper to put zero gain unity at 12 o'clock. 
I like ham, and jam, and spam alot

antonis

Re: Is this Timmy Schematic correct?
« Reply #9 on: May 02, 2018, 05:54:22 AM »
I've got a more artistic version than Stephen's... :icon_lol:  :icon_lol:

Can't follow your signature changes, Stephen..!!