Completed BYOC Analog Vibrato (VB-2) build, with pics

[gbkd80]

I spent a good amount of troubleshooting on this one, onlyto find out the pinouts on the A733s were wrong. I was tracing out the schematic, and everything changing right at Q12. I was checking the 733 datasheet over and over again. And everything I checked was pointing to the pinout being ECB, same as the 945s. The trannies I got were A733 P331, and I read in a post somewhere here about not all 733 pinouts are the same. But the datasheet kept proving that wrong to me. It wasn't until I looked at the parts list again and I saw the 733 noted as EBC pinout. So I socketed the remaining 733s and crossed the leg over, figuring the PCB layout was done with EBC in mind, and sure enough, everything is working.

Now, the 2SA733 shows a pinout of ECB. The KSA733 has a pinout of EBC. If you google "2SA733 EBC pinout" there are a lot of results leading to the BYOC page. Is it possible the BYOC kit actually comes with KSA733s? Or what's up with that? Seriously that was like a 1am revalation...

I even got the pedal to fit comfortably in a 1590BB whereas the kit comes with a slightly deeper box.  I wasted a box though because I followed their drilling template, which I guess I now know was for the deeper enclosure, and I couldn't clear the in/out jacks with the pots.  So I ended up drilling another box and dropping the pots down a bit, closer to center, so everything would clear.  Then I insulated the electrolytics and bent them over to avoid hitting the bottom plate.  Everything fits nice and I'm very happy with the outcome of this one.  Also, great pedal!

[Mark Hammer]

A handsome build.  My tip of the hat.

Personally, I prefer to have a bit more space between stompswitches and controls, when it is feasible, but that may just be my foot-precision issue.

[duck_arse]

don't you just LOVE datasheets? the KSA shows a higher and lower range of hFE, and a few other differering numbers to the 2SA755 sheet. oh, and the pinouts are a bit different too.

nice work, and nice work. (why are they using weird japanese transistors?)

[armdnrdy]

Here's my take on the VB-2 with the BA662 to BA6110 conversion.

I routed my own single sided board with on board pots, jacks, and ramp on/off switch.

The board was designed to fit in a 125BB enclosure.

Great sounding effect!

[Mark Hammer]

Actually, now you've got me thinking.  I own a Pearl PH-44 phaser.  Great little unit  One of the features of the unit is that it has a ramp-up/ramp-down feature when changing between fast and slow speeds.  I'll have to look into the switching arrangement, since many e-switched phasers simply lift and re-engage the phase-shifted signal to "bypass" the effect.

But, assuming it was feasible and easy to disable the dry signal and still retain effect bypass, I could have a ramped-up vibrato.  The slow speed can be set slow enough that the pitch shift would be barely audible to inaudible.  Once it begins to move towards the fast speed, however, the vibrato effect would become more audible.  In the VB-2, it is the vibrato depth that gets modulated to make the effect more audible.  What I'm pondering is greater effect intensity arising from the modulation speeding up.

Hmmm.....

[gbkd80]

Here's my take on the VB-2 with the BA662 to BA6110 conversion.

I routed my own single sided board with on board pots, jacks, and ramp on/off switch.

The board was designed to fit in a 125BB enclosure.

Great sounding effect!

That's actually really great, did you use a layout to etch that board or did you design one from a schematic?  I was looking for something like this for more of a challenge but the BYOC board was busy enough. 

[gbkd80]

A handsome build.  My tip of the hat.

Personally, I prefer to have a bit more space between stompswitches and controls, when it is feasible, but that may just be my foot-precision issue.

Thanks Mark

I would have been able to mount the pots higher if I went with the correct enclosure, but because I needed everything to clear and I already had several 1590BB boxes, I decided to use what I had and just drill them down a little lower so the PCB with the mounted stereo jacks would clear them. 

[armdnrdy]

did you use a layout to etch that board or did you design one from a schematic? 

I designed the board from the original Boss schematic, the BYOC drawing which included the BA662 to BA6110 conversion, and did a bit of research for that conversion on various synth sites.

[Fender3D]

Great work Larry, and awesome layout

[CheapChip]

Is Larry's layout still available, please?
I can't find anything on this topic...