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I built a wonderful sounding Total Recall. The Feedback control, however, can only be used in the first quarter of its range. After that it oscillates badly. The distortion of the pedal is a somewhat higher than expected.
What can be wrong? All the voltages check out and the sound with the Feedback control to zero is fine.
Would recalibration solve the early feedback problem?
Anyone?

Kind Regards
Henry
Netherlands

[BluesGuitarLuki]

Brian instructs you to take your time and coffees when populating the Harbinger One boards. DO  IT! He knows! I didn't put a resistor on the PCB that hadn't been measured first. Populate the resistors in order!

I used the very thin aluminium cap of a perfume bottle as a light shield. Reflective inside! I stuck it to four soldering pins with Blu-Tack.

The alternative 18V lamp that Brian suggests in the build document was easier to obtain than the  12 volts unit here in the Netherlands and I could only get LDRs with a dark resistance of approximately 6M but the Vibe worked perfectly straight away. The sound cannot be compared to any other chorus or vibrato, as Brian rightly mentions! Because the lamp is an 18 volts unit on an LFO that operates on 15 volts, I assume I could increase the brightness of the lamp somewhat (GAIN trimmer). The LFO will never swing higher than 15 volts, will it? I assume the maximum brightness of the lamp is reached at 18 volts. Is this correct Brian?

I used the switching arrangement as suggested by  BluesGuitarLuki  at http://fuzzypedals.blogspot.nl/2014/10/building-univibe-clone.html.  The blog describes  the 2013 Harbinger One, but all he writes applies to the 2015 version as well. His arrangement  uses one dual two colour (common anode) LED that serves as a chorus/vibe indicator, as a blinking speed indicator and as an on/off LED. For this a DPDT toggle  is needed instead of the original SPDT Chorus/Vibe switch.  I used flat lever solder lug switches and "tied" them to the board with very short wires, looped the wires through the lugs and then through the holes in the PCB. Additionally I used the square pad a little to the left of LDR1 to turn off the lamp in bypass mode. White wire in picture. This shorts the base of Q13 to ground and shuts off the lamp. This should considerably lengthen the life of the lamp.

What do you think of the graphic? I found it on the internet, of course.  I tried to reach  "omerbc.deviantart.com"  to get the artist's permission to use it for this one-off, but I could not reach him/her. Granted?
My experiences with printable decals range from very  good to very crappy! Therefore some experimentation was required. I designed  the graphic in Photoshop and then printed  it on my Epson printer (Stylus Photo R1900) on Epson Premium Glossy paper. This printer uses glossy (yes) pigment ink instead of the more common dye inks. The printer even has a glossy clear ink cartridge. These inks are waterproof!

I used very thin (2/10 of a millimetre or so) double-sided adhesive sheet to stick it on the factory painted Hammond 1590BBS. This enclosure is slightly higher than the BB type. The double-sided adhesive sheets are normally used to stick photographs on wood or metal and such.
I then sprayed at least  8 or 9 coats of clear lacquer on the graphic only. I tested it with ordinary acrylic lacquer and with nitro-cellulose lacquer, left over from my Les Paul build. Both worked well on the Epson paper, no smearing or blurring at all. Let it dry for two days before touching! I used masking tape to prevent the glossy lacquer from getting onto the matte, slightly textured sides of the Hammond enclosure. The glossy top and the textured sides and bottom make  a very attractive combination. Durability has yet to be established, but it sure looks good, doesn't it?

Sorry, wrong white balance on photos. Corrected!

Henry (hjhjazz)
Netherlands