So, testing my new chorus before boxing. All hooked up, I get clean signal through when engaged, but no chorus (regardless of where bias is set). My first assumption is my 3007 is bad (Its been sitting in my parts box for almost 4 years, from ebay seller "sharpseller2000"). They were shipped stuck into a piece of styrofoam so... yeah static safety not observed.
Anyway, the only 9V battery I have on hand at the moment is hovering around 8.2V, so all values are a bit lower than suggested in the build doc. I will test again tomorrow with fresh juice.
4558:
1- 4.55
2- 4.55
3- 4.48
4- 0
5- 4.51
6- 4.54
7- 4.53
8- 7.98
tl062
1- ~
2- 3.89-4.01
3- ~
4- 0
5- 3.90 - 4.02
6- 2.81
7- ~
8- 7.89
3101:
1- 0.52
2- 2.3-2.7
3- 6.8-7.1
4- ~
5- 4.11
6- 0
7- 4.03
8- 7.88
3007
1- 6.0
2- 6.0
3- 4.02
4- 0
5- 0.52
6- 3.72
7- 4.06
8- 7.87
Again, I get perfectly clean signal through, through full bias trim sweep, and at all points of the pots. With guitar unplugged (just listening to the wonderful sound of my horrible wiring buzzing through the air) I can hear a very faint clicking that responds to the rate pot. I assume this is the clock?
Have you checked the circuit with an audio probe? Check for signal input at pin 3 and output on pins 7/8. I would say it sounds like the BBD is the issue. The ticking is likely the clock noise.
Regarding the ticking issue, did you drill the enclosure for top jacks? Could be the input jack is too close to the LFO (tl062)
On my mutron phaser clone I had to isolate the pcb from the jack with a copper sheet (like the ones used for guitar shielding) connected to ground.
You could also try a tl022.
And yes, an audio probe will help you isolate the problem. :)
Something I do not understand....
3101 Pin 2 goes to 3007 Pin 6
3101 Pin 4 goes to 3007 Pin 2
So... why are the voltages NOT the same?
They are not the same on the build doc either ???
Stands to reason that, if they are directly connected.... they should be the same... right?
Quote from: Boba7 on July 27, 2016, 03:05:17 PM
Regarding the ticking issue, did you drill the enclosure for top jacks? Could be the input jack is too close to the LFO (tl062)
The circuit isn't in an enclosure yet, this was just done gator clipping the I/O and power leads to a test rig.
And, I shall test with an audio probe when I have a chance. We shall see what is up!
Quote from: somnif on July 27, 2016, 08:15:28 PM
Quote from: Boba7 on July 27, 2016, 03:05:17 PM
Regarding the ticking issue, did you drill the enclosure for top jacks? Could be the input jack is too close to the LFO (tl062)
The circuit isn't in an enclosure yet, this was just done gator clipping the I/O and power leads to a test rig.
Oups, my bad. Could still be that a wire came too close to the lfo. And a tl022 could make a difference (I still have to try myself a tl022 against a tl062)
Good luck, hope the probe helps!!
Ok, so, turned out my local electronics store actually had a 3007 on the freaking shelf (Well, an NTE1641, close enough. Okay so its an SK10239, who's counting.). New chip in, and it works just fine! Though the.... "intensity" of the chorus doesn't quite seem to match what I've heard in demos, that may be my ears attempting to mess with me. Also had to turn the bias trimmer very nearly full way before the effect kicked in (on a clock face from 7 to 5, it kicks in around 2-3).
But for now, I'm getting chorus, so I'm happy.
Next question, if I were to put a Roadrage/3PRR in the box with it, would I use the 15V pad? The build doc says to not go over 12V. Would I just swap the regulator on the board from an LM7815 to a LM7812?