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Gday all,

I'm just about to start my Total Recall build and I'm wondering what experiences people have had building it for 18V instead of 24V. Any problems feeding the Lm7915 so close to minimum input voltage (17.5V)?? Any other problems come up?

Thanks,
Todd

G'day,

So, I'm having trouble with my tri-vibe build. I've used the PCB sold by Chi_boy, build doc
http://home.comcast.net/~gprause/BuildDocs/TriVibe_V3.1_Build_Doc.pdf

LM13600 datasheet http://pdf1.alldatasheet.com/datasheet-pdf/view/8638/NSC/LM13600.html

Firstly, I have reflowed all solder joints, so there shouldn't be any cold solder joints. I have checked all resistor and capacitor values visually.

In the vibe position there is basically no sound (though if the amp is turned all the way up low volume sound can be heard)
In the other 2 switch positions the signal passes through un-modulated at about unity volume. This tells me that the signal is bybassing the 13600 and instead going through R18 or R19

I've narrowed the probable problem area down to pins 9, 10, and 12 of the LM13600.
Their respective voltages are 1.5V, ~0.2V, and ~0.2V. Based on the voltage lists I have found elsewhere, pin 9 should be 4-4.5V, and pins 10 and 12 should be approx 5.5V. The voltages at all other IC pins measure correctly.

Following the path with a signal probe, the first half of the IC works as expected, that is, signal enters at pin 7 exits at pin 8 with modulation. Depth and rate knobs affect modulation. All working as it should.
Next, following the path from pin 8 through C4(1n5) to pin 10 the signal is as it should be. It is at pin 9 where the signal basically stops. Now, if I absolutely crank the volume on the amp, I can hear the sound of the modulated guitar signal (definately the guitar signal, not some LFO noise).   

So, I'm hoping for some fresh thinking and possibly somebody with a better understanding of the LM13600 or the circuit. I can post pictures if needed, I'm just waiting on the battery in my iphone to charge.

Thanks,
Todd

Does anybody have a source for the 2M linear Rez pot??
I've checked around but can't seem to find it.

Just curious, has anyone gone down the silicon path with their Pastyface build??
Any thoughts? Favourite transistors, component changes, etc.

G'day all,

Just a bit of a question. I purchased a tube cricket kit from Officially Licensed Circuits on the 5th August and haven't heard anything since. I realise that it can take a bit of time to get it ready to ship, and then getting it here to Australia, but I haven't received any e-mails confirming the order etc. I have also sent 2 emails to them just to find out if I need to be concerned or not and haven't received any replies.

So, has anybody bought from them in the past? Had good dealings with them? Do I need to be worried??

I realise that this isn't a Madbean issue, but thought there might be someone here to allay my fears.

Thanks,
Todd

G'day all,

  I just finished putting together one of Haberdasher's op-amp boards.
I would have to say I'm pretty happy with it.
  Built straight up to the specs in the build documents, with no problems there.
Haberdasher suggested that there might be a bit of noise, but as he pointed
out, it isn't any worse than an ordinary big muff. I didn't find it to be
any worse than my Green Russian clone and to be honest a bit of noise never
bothers me, adds to my tone!!
  An interesting pedal in comparison to my Green Russian, doesn't seem to get
as muffled in certain knob positions, and it seems to be overall a bit louder. And,
they sound great stacked!!!
  So, great PCB and easy build, so I'd definately encourage everyone to build one.


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