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(1) Project: Man O' War DX powered by OneSpot 12V supply (actual reading: 11.73V)

(2) Issue: Unable to successfully calibrate. I'm stuck on biasing the first MN3005. I get a signal at pin 7 of IC3, however the signal at pins 3 and 4 of IC3 have a high-pitched whine mixed in and rather than getting a delay, the signal repeats and ramps up to a high-pitched oscillation.

I'm getting a very high-pitched, amplified signal mixed with the dry signal at pin 7 of IC2a.

Voltage at pin 1 of IC2 is around 1.2V (build doc has 0.88V) all other voltages before the first BBD are in spec.

(3) Steps to resolve issue: I probed the signal path from the input and confirmed part values. The dry signal gets to IC2 without anything remarkable. Reflowed joints. Removed Q2 and Q3 (NPN Si) and put in sockets. Originally had 2n5088 devices in each spot, same issue and voltages when replaced with 2n3904 devices.

(4) Substitutions: Feedback pot is 25kB instead of 20kB. MN3005 sourced from CabinTech; V571 from SBE.

Pictures attached. IC5 has been removed for calibration purposes.

Anyone know of a source for Hammond 1590B2 enclosures or workalikes (NS, etc.)?

Hiya all. I'm not sure if there's still interest in this circuit, but I'd appreciate some advice here. I've been working on modifying the Clari(not) circuit. I've added an envelope/LFO modulation switch and a feedback path. I'm currently stuck on a gain switch.

Instead of the usual mod of cutting the connection between pins 1 and 8 of the LM386 (since there can be a loss in the wild modulation with this method), I'm trying to split the input into two buffered paths: one path (always on) goes to the LM386 while the other bypasses the LM386 and connects to the junction of the 10k and 22k resistors leading to pt2399 pins 15 and 16. In clean mode, the input goes to the LM386 to drive the LED for the LDR, but the audio signal goes to the 10k/22k resistor junction. In fuzz mode, the circuit input is buffered, but otherwise the same as stock.

All of the modifications work as expected—except for the input in fuzz mode. I'm getting an extremely gated, sputtery fuzz that completely cuts out with high amplitude input (i.e., hard strums with humbuckers). I've used an audio probe and can confirm that the sputtering is present at pin 5 of the LM386. I'm attaching the schematic for the input of the circuit and the power section. Any insight here would be greatly appreciated. Also, I can post the entire schematic if there's interest.

Cheers

I've used wall warts and daisy chains forever. I'm thinking about upgrading to a PSU, though, and put together a proper pedal board instead of chaining everything together whenever I set up. My chain is almost exclusively analog 9v center negative effects (i.e., no high-current digital pedals). There are a few with 12v and 18v inputs (and a DMM at 24v). I'm wondering what's worked and what hasn't.

I'm also interested to hear thoughts on pedalboards (brands, styles, velcro or not, etc.).

I've been using some laser etched acrylic faceplates on builds lately. On all of them to this point, I've cut holes in the faceplate for pots/switches so that the hardware will hold them in place. With this latest project, the design didn't really work out so that I could use that method, so I've got an acrylic faceplate that needs to be affixed to the powder coated enclosure without the aid of hardware. Are there particular adhesives that folks have used for this purpose with good results? I'd rather not use 3M foam tape (since it adds more height than I'd like and I don't know about longevity), but I'm open to any other options.

I was thinking about building up a noisy cricket mkii amp with a switched headphone out option. Since I have some parts of my chain that are stereo out and headphones are obviously stereo, I wanted to have the option of a stereo in. Would I double up the entire circuit—doubling the poles and replacing pots with dual gang—to do this?

I think my main question is whether I need a summing circuit to handle mono. Or, should I use switched jacks and just have one circuit channel run if there's only a mono input? That makes sense for a mono in / mono out, but I'm not entirely sure how to run a mono in / double mono (for the stereo headphone) out with just switched jacks and no physical toggle. Hopefully all of that is clear.

I'm attaching the mono schematic.

According to the build document, the emitter of Q4 (2n3904) is 0V. I'm getting a reading of about 4V; from the schematic, it seems like a non-zero reading is appropriate here. I wanted to confirm voltages even though the unit is functioning as expected. All of the other readings are inline with the published figures.

Does anyone have any information about this module? I've never seen this before.

https://smallbear-electronics.mybigcommerce.com/accu-bell-sound-effector-reverb-unit/

I've got some knobs that have burrs around the set screw holes. What is the best way to remove these short of muscling the knob onto the pot shaft?

I've just had a 3PDT from a previous build (about a year or so old, regular but not 'strenuous' use) fail. The switch mechanism works as before (from a tactile perspective, at least), but the connection between poles 8 and 9 is no longer being made. Every other switch element behaves as expected (including the connection from 8 to 7). Is this normally how they fail? Replacement is simple and easy, but I'm a little curious about what exactly went wrong.

Am I correct in assuming that, in the case that all components are rated appropriately, the maximum input on VFE projects can be interpreted from the zener value on the switching board? I took a look at the VFE project pages and compared the listed power input values to the zener listed in the switching board document, and they seemed to match up:

• The Scream: 9-18V with 18V zener
• Choral Reef: 9-15V with 16V zener
• Merman: 9-12V with 13V zener

Another question I have is about the 4558 voltage rating: it lists an operating voltage of +/-18V. With caps, I know a little bit of breathing room is important (e.g., using caps rated at 25V when running at 18V), but is this the case with this IC? The Vid (input differential) is listed at +/-30V; does this mean that the voltage potential must not exceed 30V? If that's the case, the 18V supply with a zero ground should be totally safe?

https://www.mouser.com/datasheet/2/294/NJM4558_NJM4559_E-364362.pdf

With my LP, I was getting a decent amount of distortion from the Klein Bottle itself. I adjusted the trimpots to mitigate this, but I had to go pretty low (~9 o'clock). The LP has humbuckers (so higher output), but that's no where near the signal amplitude of line level (which the KB can handle). This, of course, could because I'm running at 9V. I'm curious to know what experience other people have with the makeup gain trim.

Does anyone know of a (US) source for the 9203 photocell that's in stock? If not, is there a workalike or a vactrol that can be used in place of the photocell/LED?

I have a small batch of J201s that I'm thinking are actually J202s (the Idss measurements for the J201s are an order of magnitude higher than the spec sheet and in line with J202 figures). If they are in fact J202s, how can I possibly use them? Can I use these in buffers?

Cheers

Is this going to be updated with the other projects that have gone out of stock? The SnackShack layout in particular is a good platform for a bunch of one-knob fuzzes.

Does anyone have vector drawings of lumberg audio jacks for working out drill templates?

The BAT Pharaoh BMP variant has 10uF tantalum input (followed by a 100k resistor to ground) and output capacitors. I know that the 100k resistor is the bias resistor for the transistor (base to ground), but is this forming a high pass filter with the input cap?

Would there there be really a huge difference replacing the 10uF tantalum capacitors with 1uF film capacitors? If the input is forming a high pass filter, the R-C calculation puts the corner frequency for the 10uF cap is 0.2Hz and for the 1uF cap is 1.6Hz. Both of these are far below audible range, so I'm left thinking I've misunderstood something here. All of that is aside from the output cap which to me just seems enormously wide open at 10uF.

Attached is the schematic from Kit Rae's Big Muff page for reference.

FYI for phaser, filter, etc. kids (and anyone sitting on a Sawse board), SBE has dual photocoupler reissues from Xvive in stock.

(VTL5C4/2 and VTL5C3/2)

VFE is offering Klein Bottle kits (no option for just the board/MCUs) at a few different tiers (SMD op amps, knobs, etc.) at http://vfepedals.com/diy.html. The basic kits include the PCB; a drilled, painted, and labeled enclosure; MCUs; and pots, switches, jacks, LEDs, and wires.

Expected to ship before 4/15/19.

[Project Name]

(1) Project Name: Pork Barrel 2015 rev.1
(2) General description of the problem:
The chorus works wonderfully until the rate LED (LED2) is wired up. Here, the engaged sound is pretty much the same as bypassed. Also, the rate LED remains solidly lit (no tracking with rate/depth).
(3) Steps that you have taken to try to resolve the issue:
I've rechecked parts and soldering. I removed and checked all off-board wiring and pots (to take a look under). Cleaned flux residue. Checked for unforeseen continuity with DMM.
(4) List any substitutions you used for parts/values:
Board is built to stock specs for the MN3101/3007 combo (sourced from SBE). Effect is powered by a 3PRR providing 12v.

I can provide measurements soon.