Earthquaker Devices - Talons [traced]
- thesmokingman
- Breadboard Brother
zed has the presence control right and its tied to the 1u C10 on his schematic, no need for a question mark there.
your op amp pin 2 culprit is the 1uf C11 you have circled . it runs from pin 2 to 1K resistor R12 and that runs to the positive side of a 10uf. R12 is also connected to R14 10k, R13 220K, R93 10K, R92 10K at the same cap. vref
your op amp pin 2 culprit is the 1uf C11 you have circled . it runs from pin 2 to 1K resistor R12 and that runs to the positive side of a 10uf. R12 is also connected to R14 10k, R13 220K, R93 10K, R92 10K at the same cap. vref
- zedsnotdead
- Breadboard Brother
Guys,
I just finished tracing the circuit. I am about to re-do all the references and... there's a surprise on "presence"
I will post it soon, later this evening.
I just finished tracing the circuit. I am about to re-do all the references and... there's a surprise on "presence"
I will post it soon, later this evening.
- zedsnotdead
- Breadboard Brother
Ok guys, here it is my final trace. I double check the tracks and think it's accurate.
Mind that I re-did a NEW component reference annotation. Here it is:
So, if this is correct (which I hope it is) who is interested on designing a 9mm pcb-mounted pot, 1590B-friendly PCB layout...?
Mind that I re-did a NEW component reference annotation. Here it is:
So, if this is correct (which I hope it is) who is interested on designing a 9mm pcb-mounted pot, 1590B-friendly PCB layout...?
- thesmokingman
- Breadboard Brother
- zedsnotdead
- Breadboard Brother
No, just V+ (after 100R), on pin 8. GND doensn't power anything.EBRAddict wrote:Very cool! So the TL072 op-amp powered with V+ and GND?
- storyboardist
- Breadboard Brother
Information
I should have one for you later this afternoon.zedsnotdead wrote:So, if this is correct (which I hope it is) who is interested on designing a 9mm pcb-mounted pot, 1590B-friendly PCB layout...?
- Nocentelli
- Tube Twister
Information
- Posts: 2222
- Joined: 09 Apr 2009, 07:06
- Location: Leeds, UK
- Has thanked: 1152 times
- Been thanked: 954 times
The pedant (and science teacher) in me wants to say that strictly speaking, the opamp Is powered by ground at pin 1 and +9v at pin 8: without ground, there would be no complete circuit and so no power would flow.zedsnotdead wrote:No, just V+ (after 100R), on pin 8. GND doensn't power anything.EBRAddict wrote:Very cool! So the TL072 op-amp powered with V+ and GND?
modman wrote: ↑ Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...
- zedsnotdead
- Breadboard Brother
And you are right Sir!Nocentelli wrote:The pedant (and science teacher) in me wants to say that strictly speaking, the opamp Is powered by ground at pin 1 and +9v at pin 8: without ground, there would be no complete circuit and so no power would flow.zedsnotdead wrote:No, just V+ (after 100R), on pin 8. GND doensn't power anything.EBRAddict wrote:Very cool! So the TL072 op-amp powered with V+ and GND?
Something like having a motor running without a gas exhaust tube. I hear you, I hear you...
- Nocentelli
- Tube Twister
Information
- Posts: 2222
- Joined: 09 Apr 2009, 07:06
- Location: Leeds, UK
- Has thanked: 1152 times
- Been thanked: 954 times
Also, the battery's energy is transferred to electrons which travel FROM ground to +9v.
modman wrote: ↑ Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...
- storyboardist
- Breadboard Brother
Information
As requested, here's a PCB layout with 9mm board mounted pots. Mount them from the solder-side of the board. In and out pads kinda ended up in a weird place, but shouldn't really be a problem. Board dimensions are 2.1" wide, 1.9" tall in case it doesn't scale right. I'll probably do another layout for 16mm board mounted pots, but that's gonna take some re-arranging. Enjoy!
- johnk
- Resistor Ronker
I etched my own PCB version for it but, IMO something's still not right. everything works as it should (the drive, eq, presence etc) but there's just way too much gain and the distortion gets really ugly/splattery when at 9:00 and above.
- zedsnotdead
- Breadboard Brother
johnk wrote:I etched my own PCB version for it but, IMO something's still not right. everything works as it should (the drive, eq, presence etc) but there's just way too much gain and the distortion gets really ugly/splattery when at 9:00 and above.
Could it be a wrong cap polarity? Maybe C4 1uF ?
- johnk
- Resistor Ronker
BTW, I just tried it with polarized electrolytics for the 1u's (installed with the correct polarity) with the same result.
even with the gain not turned up very high there's an ugly fizzy decay that i'm sure isn't supposed to be there, which to me, reminds me of opamp clipping.
it would be great to solve this since everything else works perfectly.
even with the gain not turned up very high there's an ugly fizzy decay that i'm sure isn't supposed to be there, which to me, reminds me of opamp clipping.
it would be great to solve this since everything else works perfectly.
- zedsnotdead
- Breadboard Brother
Talons almost behaves like a boost with gain=0, so it's almost clean.
I just re-checked the connections and values mainly on drive section, There's one minor (i think) correction: R4=4,7K, not 4,6K.
I don't really think it would make a difference, but I could be wrong..
One thing though, are you using log or linear 500K pot for gain? If you are using log, mind the lug numbering - lug1 connects to R4.
I just re-checked the connections and values mainly on drive section, There's one minor (i think) correction: R4=4,7K, not 4,6K.
I don't really think it would make a difference, but I could be wrong..
One thing though, are you using log or linear 500K pot for gain? If you are using log, mind the lug numbering - lug1 connects to R4.
- zedsnotdead
- Breadboard Brother
great!!!
How does it sound?
How does it sound?