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Cabintech now stocks FV-1 chips. Thought others might be interested in low cost FV-1 chips with very reasonable shipping charges (in the US).

https://www.cabintechglobal.com/fv-1

I'm working on an EHX double tracker layout. The Flim Flam doesn't work for me. In looking at the Flim Flam (MN3005) schematic compared to Scruffie's MN3202 based double tracker, there are a few differences outside the BDD differences. First, C9 (flim flam) is connected to pin 6 of the Op Amp, where as the equivalent capacitor (C10) of Scruffie's schematic is NOT connected. Second, the diode near the CD4047 is different in the two schematics. In the flim flam, pin 3 goes through the diode to R18, where as pin 2 goes through the diode to the equivalent resistor (R17) in Scruffie's schematic.

Neither the etched Flim Flam nor a fabricated PCB that I made using the Flim Flam schematic ever worked for me. According to someone on an archived post on DIYStompboxes, Scruffie's schematic and layout worked. I'm wondering if these discrepancies in the schematic could be causing the Flim Flam to fail.




Edit: fix size of images

I'm trying to bring a CE-1 Preamp schematic to life. I found the schematic on the internets, and it is supposedly verified. The circuit centers around a SIP7 TA7136. Tracing with an audio probe, I get signal all the way to pin 2 and only faint, garbled mess at pin 6. The IC voltages seem a bit off to me, as well... no IC (w/IC):

1 = x (14.5V)
2 = input good (7? variable with vol pot)
3 = x (14.35)
4 = -17.6 (-17.5)
5 = 15.45 (15.45)
6 = output bad (14.87)
7 = 15.6 (15.4)

I'm not very familiar with the TA7136, and the only datasheet I could find seems to be lacking in critical info (http://www.datasheetcafe.com/ta7136p-datasheet-pdf-amplifi.../).

The power section of the schematic also seems odd. The author claims +/- 13V should feed pins 4, 5, and 7. Clearly, I'm a bit off from there.

My questions... is the TA7136P connected properly in the schematic? Also, how would I get the voltages to where they should be? Would a zener be better than 4001+resistor? Or would a higher resistor be the solution?

I'm struggling to troubleshoot my MOW DX build. It passes sound, but there is no modulation/delay. The rate and bypass LEDs work, and the LDR LED flashes. Based on the voltages I suspect there is something weird going on with Q6 or Q7 which then throws off the voltages for the clock and BDD. I replaced Q7, R51, and R53 to no avail. I also visually verified that R50 and R52 are correct. Anybody know why the collector voltages would be so low? Am I right in assuming this would cause the clock and BDD to not function properly?

Voltages:
Q1 (2N3904; CBE) - 12.4, 4.2, 3.76
Q2 (2N3904; CBE) - 12.4, 2.85, 2.25
Q3 (2N3904; CBE) - 12.4, 7.4, 6.8
Q4 (2N3904; CBE) - 12.4, 7, 6.5
Q5 (2N5088; CBE) - 0.45, 0.45, 0
Q6 (2N5088; CBE) - 2.2, 0.5, 0
Q7 (2N5087; CBE) - 2.15, 12.2, 12.2

IC1 - 6.12, 6.13, 6.13, 0, 6.12, 6.12, 6.12, 12.4
IC2 - 1, 1.8, 1.8, 0, 1.87, 1.87, 2.9, 1.87, 1.87, 4.3, 4.3, 1.87, 12.4, 1.87, 1.87, 0.9
IC3 - 12.4, 0, 6.9, 5.8, 0, 11.79, 6.23, 0.8
IC4 - 11.8, 0, 0, 11.8, 11.75, 2.8, 3.7, 0.8
IC5 - 12.4, 0, 5.3, 6.3, 0, 11.7, 5.25, 0.8
IC6 - 11.7, 0, 0, 11.7, 10.6, 2.6, 2.1, 0.8
IC7 - ?, ?, ?, 0, ?, ?, ?, 12.2

Pictures:
Solder

Component

I just picked up a 70s EHX Bassballs and a 70s Ross Phaser for prices much lower than I would have expected. To be clear, these were not one-off, random deals. The market value on these is lower than I expected. I'm wondering if there are other effects that people have similar opinions about. I'm not a music dealer and I'm not looking for "investment" ideas. It's more of 'now is a good time to buy' type of thing. I also realize price and value are both highly subjective, so I'm not expecting a consensus. Just curious what other people think, and it could be something interesting to discuss.

Does anybody have any experience programming Stomp LFO chips from Electric Druid? The code is freely available on his website, but it doesn't download as a .hex file and I have no idea how to convert it to a format that my Pickit3 recognizes. I also tried to use my GQ-4X4 to download the code from a preprogrammed chip. However, the GQ-4X4 doesn't have a PIC16F18313 in its device list. I submitted a request to GQ-4X4. Hopefully, I hear back from them.

As I sit here typing this, I realize that I never tried to use the Pickit3 to read a preprogrammed chip. I'll try that now.

Anybody have any suggestions?

Dual VFE Blues King...it's a tight fit. I used BA282 and D9B diodes for this one. I like this double board format. I'll try to do dual Choral Reef (chorus) and/or Tractor Beam (Phaser) next.



I also tried out the Woodchipper from the VFE files pack. It's based on the Brassmaster. It uses a somewhat expensive (~$16) miniature transformer. This thing rips!

Is the build doc correct? The schematic and BOM say 2N3965. However, the board appears to use an NPN (2N3565) and other Percolator schematics do, as well. Confused.

Does anyone have a schematic for the Yodeler PCB? The build doc is inaccurate and illegible. None of the components are listed on the Yodeler .brd file from VFE, either.

XP-ALL mod for Digitech Whammy Wah (XP-100). The mod gives the XP-100 all four models: Wah, Modulation, Space Station, and Reverberation. I found the RAM and EPROM on eBay. Dino (DeadendFX) burned the EPROM. XP-ALL daughter board was purchased from DeadendFX. Instructions (also from DeadendFX) were superb, as usual. The mod is a 8.5/10 on a Fuzzface to Ludwig Phase II difficulty scale. Attaching the wires to SMD pads and wiring the rotary was the hardest part.  I was hesitant to do the output volume knob mod before I knew the XP-ALL mod worked. I will probably go back and wire that up, at some point. I also elected to not install the LED to simplify the wiring. That's why the black wire (ground) is coiled up. It's only used for the LED.

Works like a charm

Trying to build a Clari(not) clone, but I'm not getting any modulation from the LED/LDR. PT2399 modulated signal works fine, though. I get ~5V from pin 5 of the LM386 and the anode of C14. I don't see any voltage from the cathode of C14 which feeds into the tracking pot and later the LED. If I jumper the anode of C14 to any pad of the tracking potentiometer, the LED lights up, so there isn't anything wrong with that part of the circuit. Does somebody know where the LED is getting power to emit light? Based on the schematic, I doesn't make sense to me how there could be any voltage through the cathode of C14 and eventually to the LED. Pretty much every other circuit with a LED/LDR that I've looked at, the LED receives some amount of supply power.

On a related but separate note...I assume a signal causes the LED to dim/brighten and produce the modulated effect in the Clari(not). Is this true? If so, how is that happening? Does the PT2399 contribute to this?

Here is a link to a common schematic for the Clari(not)... https://photobucket.com/gallery/user/midfielectronics/media/bWVkaWFJZDo1OTExNzIyNw==/?ref=

I want to make a PCB for an FV-1 EEPROM selector switch according to this schematic... http://www.hexeguitar.com/diy/utility/fv1progsel

It uses a BCK1001 rotary switch... https://www.newark.com/lorlin/bck1001/rotary-coded-sw-16p-hex-0-15a/dp/38AC0718

I contacted the switch manufacturer (Lorlin) to ask for a footprint. They gave me a .stp file. I guess this is a CAD file? Is there a way to convert this into a .lbr file that I can use in Eagle? Or is there another recommended way make the footprint?

There was a pedal that circulated through social media where a guy used a home etched daughter board to switch between 2 EEPROMs for his FV-1 build. It was rad. I'm hoping to make a fab'd PCB that I can share with the community.

Recently completed a Ludwig Phase II Synthesizer. PCB from Dead End FX https://www.deadendfx.com/product/ludwig-phase-ii

The build guide for this project is superb. The pedal fired up on the first try and the tuning was easily accomplished by following the instructions in the guide. The biggest challenge (and it was a big challenge) was the off board wiring. There are a lot of wires that run between the board, switches, and jacks. Since one board mounts to the enclosure and the other mounts to the back plate, I used mostly stranded wire for its flexibility. I'm more accustomed to solid core wire, so the strands fought me getting them through the PCB holes. Also, there are several points that require 2 (and sometimes 3) wires in 1 hole. To make this easier, I soldered a short 16ga wire in the hole and used it as a standoff to solder multiple wires.

The original unit is a monstrous cabinet with an expression pedal that folds out. Adding a expression pedal to this clone is doable, but it's not something I really wanted. Instead, I added a 10kB pot to the side and put on a large knob that I can toggle with the side of my foot. It works reasonably well for me. I'm not a performing musician. I just make weird noises in my room.

The art was intended to capture some of the original design elements- mainly the icon and the burled wood finish.

Here are the box and gut shots...

Does anyone have any clever solutions for getting two stranded wires into one hole?

The original PS-1A is the size of a suitcase and there are single-sided etch able versions that are not much smaller. I was coveting alanp's pedals on his website and saw he made a small board. He was gracious enough to sell me a board. He was also patient when dealing with my dumb questions about the switching. Thanks, alanp!! It fit without any fuss into a 1590BB. Not bad. The fast and slow phase settings sound really good. The medium has this weird asymmetric phase blip thingy. I tried to match JFETs (8x2n5457 ), but I must've been a bit off. Oh well, I love it nonetheless!

Here it is...

The good:
1. Tremolo sequencer, LED sequence indicators, and all potentiometers work fine.
2. Tap tempo works well.
3. Sequence output operates tapanator wah/phase/tremolo pedals fine.
4. IC1-4 and REG voltages are all within specs on BOM.
5. LED side of Vactrol 1 causes an LED to flash when placed on the vactrol pins. Thus, I assume vactrol 1 is getting the appropriate signal.

The bad:
1. The wah signal is a continuous, muffled drone. The "wah" volume pot and "gain 1" trimmer adjust the volume as expected, however.
2. Q2 S voltage is lower than the value listed in the BOM (1.34 vs 2.7). I swapped ~5 different 2N5457 from a variety of manufacturers and vendors, but 1.34 was as high as I could get it.
3. Q1 C is higher than the value listed in the BOM (5.7 vs 4.7).
4. Unlike Vactrol 1, the LED side of Vactrol 2 does not cause an LED to emit light when placed on the pins.
5. The "PATT" LED near the tap tempo switch does not work. A separate LED placed on the pads also does not function. Not sure if this is an related or separate problem to that listed above. I could live with this, if everything else worked.

Anyone have any specific suggestions on how I can get the wah to work?

Voltages:
Wall wart = 9.7V

       IC1   IC2   IC3   IC4   REG    Q1    Q2
1=   4.6   4.6   5.1    0      9.42   5.7*  9.41
2=   4.6   4.6   Var    0      0        0.6   1.34*
3=   4.6   4.6   Var    4.4   5.14   0       0
4=   0      0      5.15  0
5=   4.6   4.6   Var    0
6=   4.6   4.6   Var    0
7=   4.6   4.6   Var    0
8=   9.4   9.4   0       0
9=                           0
10=                         0
11=                         0
12=                         5.15
13=                         0
14=                         0
15=                         5.67
16=                         5.15

Picture of board:

Here are a couple pedals that I recently finished. Boards are from Sushi Box FX. This is my first go at SMD. I gotta say that it's much easier to work with SMD than I originally thought. Actually, it might be easier than through hole...The "Dirt Button" is a submini (6N21B) tube overdrive with baxandall tone stack. I got distracted and the etch went a little longer that I would've liked 😐. The "Black Eye" is a dual submini tube drive (also 6N21B) based on a Soldano Supercharger GTO.

Big shout out to Nathan at Sushi Box FX for designing  these cool boards and helping figure out to how to use the Russian tubes I ordered by accident.

Dirt Button (Right), Black Eye (Left)


Dirt Button gut shot


Black Eye gut shot

How do you determine the pinout for a submini tube when all the wires are equidistant from one another? Is there a simple breadboard circuit I could build or do I have to peer into the glass and try to make sense of the various connections?

Tube is a 6N17B-V. This is where I bought it (listing contains diagram too)... https://www.ebay.com/itm/4x-6N17B-V-Miniature-Double-Triode-Tube-MELZ-Russian-SAME-DATE-05-1968-NEW/202459277971?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

I am getting ready to box a Deadastronaut Abductor Delay board, but I don't understand how to wire the DPDT. My first guess was to hook all three wires to one bank of the DPDT, but that faults the circuit.

The schematic is in the PDF here: https://deadastronaut.wixsite.com/effects/abductor-delay-ii

P.S. The board works fine with a text box.

I'm 'boxing before rocking' a tremolo for the Tapanator. It does not pass sound when hooked up to the test box. I checked voltages on the power section, and everything looks good. I used a sound probe to determine that the sound dies between the LDR and C3/TL072 (Pin 6). If I jumper the LDR, I get sound again all the way to the volume pot/out jack. Thus, the LDR is either toast, or the sound is completely muted without the Tapanator sequencer hooked up.... so my question. Does the tremolo require the tapanator sequencer to function?