Tremulus Lune Debug - No Tremolo - Need Correct Voltages

[Kearns892]

I had problems with this before, set it aside and picked it back up again.

I'm using the Tonepad layout, the only mods I've made are omitting the "fine" control and adding a "Ramp" switch with a center off SPDT similar to the symmetry mod but with only three positions (mod found here highlighted in blue on schematic: http://fuzzcentral.ssguitar.com/tremulus.php).

What Works:
Switching/ Bypass works fine
LFO section seems correct (Rate LED flashes as expected and the LED in my home made LED-LDR works)
Signal passes when effect is engaged

The Problem:
No Tremolo - only a buzz fading in and out in time with the LED (where the Tremolo should be)

I had this pedal working with Tremolo a while back, but started messing with things to eliminate ticking. Added a 100uF cap from +9v to Ground and tried and removed some other tricks to eliminate ticking and in the process messed something else up.

Both ICs are socketed and I have tried replacements of both the 4558 and the TL072 with no change in the symptoms.

I've done a lot of searching and haven't been able to find anyone who has posted the voltages from a fully working Lune. If someone has those, please post them here!

Here are my voltages:

DC Jack +: 9.50v

IC1 (TL072)
pin 1: 4.68v
pin 2: 4.68v
pin 3: 4.66v
pin 4: 0.00v
pin 5: 4.66v
pin 6: 4.68v
pin 7: 1.53v
pin 8: 9.50v

IC2 (4558)
pin 1: ~2.8-7.5v
pin 2: ~2.8-7.5v
pin 3: ~2.8-7.5v
pin 4: 0.00v
pin 5: ~3.0-6.5v
pin 6: ~3.5-7.0v
pin 7: ~1.5-8.6v
pin 8: 9.50v

Any idea what might be up with this 
Help me out please! I tried to be as thorough as possible, but if you need more info let me know.

Thanks

[Kearns892]

If someone could just quickly pop their's open and pass along correct voltages I would be much obliged 

(i.e. shameless bump  )

[Kearns892]

I hate to bump this, but I have hit a real road block here. Just a link to a thread with correct voltages would help tremendously (I've searched to no avail). No one has any input here?

If not, I'll let the thread die after this.

[Haynesarama]

Hi Jordon.

I've got the Tremulus Lune LFO on the breadboard at the moment for a different circuit.
Here's the voltages of mine running on 9V

PIN1 3.61V - 3.90 V Changing between these values
Pin2 0.14v
pin3 0.20v
pin4 0v
pin5 4.55v - 5.10v Changing between these values
pin6 3.86 - 4.11v changing between these values
pin7 same as pin 6
pin8 9.03v

I hope this helps to debug you build.
Cheers
Michael

[Kearns892]

Excellent! Thanks tremendously Haynesarama!

It looks like my values for pins 2 and 3 are incorrect. My oscillating values also look like a wider sweep. Maybe this is due to variation in pot settings when the readings were taken? Either way, this gives me one place to start. Does any one else have the voltages for the audio section?

Thanks again Haynesarama

[Haynesarama]

Hi Jordon.

No worries at all
Yeah I imagine that the values are different due to the position of the pots.
If you set your pots to 12 o'clock and post the voltages here I'll double check them for you.
You could also double check all of your wiring, the orientation of the electro caps,
the orientation of your ic's, also check for cold solder joints and poor connections as well as solder bridges with continuity
On your DMM.

Cheers
Michael

[Kearns892]

Got it. I was right, the problem was in the audio section not the LFO section. I kept going back to check the places I had tampered with to fix the ticking (there was some "sub optimal" soldering do to resoldering and desoldering, and fitting  extra components into holes). Finally found a place where I had lost continuity on the trace under the trim pot. Cleaned that up and it fired right up (of course all my probing around with the iron, and rewiring has dirtied up what was once a fairly clean build).

Still has the cursed tick, but there are plenty of threads out there on that so I am sure I can get that fixed up with a little reading.

Thanks again for your help Michael, can't believe after all that it was such a simple mistake right at the end of the signal path!

[Haynesarama]

 Hi Jordon.

Pleased you've got the tremuluslione working
You might find adding a 10n - 100n (0.01uf-0.1uf) cap
From pin 3 of the LFO dual opamp to ground.
Also A cap in series with the 470k resistor to ground at the start of the LFO
has been reported to help with ticking in some builds

Michael

[Kearns892]

Thanks, I will try that!