UVICS - Univibe In a Crybaby Shell

[Beo]

Nice etch!

So, I tried presensitized boards recently, and had bad results. I tried one board that uses regular 100W bulbs for exposure... but I think my transparency toner was not opaque enough... in the positive developer, I could see my circuit, but within a minute it disappeared and all of the resist was gone. I was left with a regular 6"x9" copper protoboard. I have a UV presensitized board, and a UV light box that I've built, but I haven't tried this yet.

In the meantime, I went back to toner transfer, but instead of using an iron, I tried my laminator that I got from Costco for kids projects. Regular copper boards fit! I did 10-12 passes through using magazine paper... and perfect even results! These were my own layouts with thin tight traces.

So, if you haven't tried it yet, pick up a cheap laminator and do your board toner transfers that way. Now if only there was a way to fit my aluminum enclosures through the laminator!

[R.G.]

Brymus, you do good work. Nice clean transfer and etch!

Some tips on fitting the PCB into the shell:
- The mounting holes need to be about 0.137"
- The reference locations are the two single mounting pads which fit over the raised bosses in the shell. The other two three-in-a-row locations are for drilling three holes then cutting/filing the holes together into a slot to fit over the threaded ends of the tension adjuster screws. I put the center hole over the locations of my adjuster screws, but I understand that shells vary in the adjuster locations, so I put extra space there to make a slot for it to fit more shells.
- The tightest height restraint is at the heel end where the power filter caps are. The caps can't be any taller than about 13mm or they'll hit the cover. To avoid this, you want capacitors which are 10mm/0.4" diameter, with 5mm/0.2" lead spacing, and less than 13mm high. Mouser's part selection app lets you pick by size among other things, which is very handy. I did the search for parts before I did the layout, and they stock several 330uF/35V capacitors with a diameter of 10mm and height of 12mm. That was the reference cap I used.
- The light shield may need some ingenuity. Of course, anything that keeps light off it while it operates will work. In fact, just the shell itself, no light shield, will probably work fine in actual use. But for debugging with it open, you may need something; and an internally reflective shield does the best job of "mixing"the light so the LDRs are illuminated evenly. You can even tape down the aluminized baggie from potato chips over them. It does not need to be perfectly shaped and sized, just there. Aluminized cardboard works, as does thin metal folded into a box, whatever fits. My recent tinkering turned up PVC pipe. The nominal 3/4" pipe can be sliced into a short ring of less than 16-17mm height (that's about what you have at the heel end of the light shield) and glued onto the PCB. Then you can tape/glue/tie a reflective top onto it. Finding stuff that happens to work is one of the joys of DIY,. The world is practically **full** of things that happen to be shaped right for a purpose that wasn't what they were intended for. I give myelf extra points when I spot something that can be used for something the original designer never thought of when they made it. 
- If you use a power supply which produces even less maximum voltage - say, 18-22Vdc at the caps - then you can use lower voltage but higher capacitance caps of the same size. There are 470uF/25V caps at Mouser that fit the 10mm wide by 12mm tall spacing
- You want to get to a total capacitance which gives you appropriately little ripple, not necessarily to fill up all the capacitor positions. I had some space free at the lower right corner edge that wasn't being used, and could not easily be used because of the positions of the I/O pads and mounting bosses. So I just filled up the space with more footprints for capacitors to provide some options. There are eight capacitor positions.
- If you can't get short enough caps, the further from the heel you go the more height you have, so the positions along the bottom are some help.
- If you an AC-output power adapter, you will need a lot of capacitance; 2000uF should be enough, and that's six 330uF caps. For an AC supply, be sure the incoming AC on the power jack does NOT contact the grounded shell.
- If you have a DC output supply that's not filtered, you still need a lot of capacitance. In this case, use lots of capacitors and put two jumpers between the pads for the bridge rectifier to let the DC directly through to the capacitors. A bridge rectifier just gets in your way if you have DC coming in already.
- If the DC supply is rectified and filtered, but not regulated, you may need the same amount of capacitance. If the supply is DC, filtered, and regulated, you'll only need one or two caps. Same comment about bridges.
- The capacitors are almost all laid out for 0.2" lead spacing 50V box style film caps. You can adapt other caps, but watch the sizes. The 0.22uF phase cap *is* available as a box cap.
- With options, comes complexity. 

The board itself lets you have a number of options.
- You can raise the input resistance to over 1M by changing the values of the first two resistors as I posted earlier here.
- There are the stock two inputs from the original univibe; you won't need both for use in a crybaby shell, so leave off the input resistor for either A or A1 inputs.
- Likewise, you probably won't need the "cancel" function, but the pads are there to do it if you want.
- You can go to darlingtons by shorting the base pad to emitter pads on the phase array transistor.
- You can hack on a "stereo" output if you like because I put in the collector resistor position and second transistor position for the fourth phase stage position. You'll have to make a separate baby board to put on the stereo mixing, and I didn't think many people would do it, so I didn't put it on the PCB where it would have had to go.
- The 1uF film capacitors I used so profusely don't have to be film. They were polarized electros in the original. You can use polarized electros, or you can use NP electros, or you can use film. The board lets you put them in.

A DIY project is a bundle of raw potential, a chance to create something new.

[SISKO]

and designed for toner transfer.

R.G., what aspects are taking into account when designing a pcb for toner trasnfer? Whats are the diferences between a this type of design and other methods?

My attempt that worked with new layout:
30 seconds on high gently pressing, hitting all the edges,then allowed to cool to handling temp.
And the paper peels off - like PNP blue without any soaking,really amazing.

So 30 seconds is all the time you heated pcb? Any longer? What was the iron temp?
Your pcb turned out so good!

[RedHouse]

Nice job on the board Brymus.

RG, I didn't get much time on your layout, so can't comment on anything electrical (sorry) but did manage to check clearnce, I noticed you moved the light chamber even farther back (towards heel of pedal) which makes the pipe-cap dimension even more critcal, but I suppose evey freebie project needs an issue or two for the builder to deal with (only fair really).

The further back you go the less available overall height the pipe-cap can be, while the inside bulb height restricion remains the same, so wiggle room diminishes, anyway, it's all good.

When I saw the v-reg there it brought the clearance thing up once again, if it's a TO-220 type you may have to instruct your builders to bend it over or whatever to keep it from hitting the bottom plate of the wah shell.

I printed your layout from the PDF and taped onto one of my un-populated Vibe-Baby boards and installed it into my (Dunlop) test-shell which I keep handy, and the area where you have your v-reg (IC1?) has about about 17mm height space from board to bottom plate, a TO-220 is about 20mm high so you will have to advise using the 78Lxx there or again advise your builders to bend a TO-220 over a bit to fit without comming in contact with the back cover plate.  

Probably sounds to you like nit-picking but a wah-shell project, unlike other projects, isn't really one that can be done from the computer desk. Because of the unique parameters of the wah-shell (other than board outline) one really should physically build/test (and rebuild) to get things to fit the enclosure properly, paying particular attention to the restrictions (diminishing height) as you approach the rear of the pedal will become evident as your build proceeds.
(been there, done that, and pioneered the t-shirt!)

Here's a pic of my rev-1 Vibe-Baby boards which discovered these clearance problems:
(I'm on rev-7 now, lots'a changes over the years)



those nice industry standard WIMA caps (back row, right side of pic) hit the bottom plate of the wah shell, actually about 1mm too high, and caused excessive pressure on the PCB when the plate was "forced" on with some shells. Back then I was making boards that were the size of the old wah PBC like you did on your UVCIS rev-1 layout, I realized there was much more available space (as you did a few posts back) and re-designed my boards to use it although I went in a different direction than you did.

At first I thought it was the mounting screw boss's were too high, and so I got out the file and trimmed a bit but wasn't happy with that solution because it was like the original problem comming back.
(metal work)

Later I found out exactly what the problem was. The thing that was not evident until I made quite a few (Vibe-Baby's) was the fact that the shells are not all the same! see the pic below which represents a span of Cry Baby shells, top one is Thomas Organ from the 60's, middle is the Dunlop 80's-06', and bottom one is the 80's-08' VOX shell before they added the hole for the DC jack and stopped chrome plating the treadle. Hard to tell from the pic but the Dunlop and the VOX have different heights but same casting numbers.


(pay no attention to the red circles, I use this pic to help my cutomers identify which type shell they have)

Anyway, if you were to measure the wall height (side skirt) distance from bottom plate surface to mounting boss's surfaces ...they are all different. And they are different from shell to shell of the same type so when you build your board with your shell (and if it fits) well, the next guy's might not, no FUD just the facts ma'am.

Investigating this reveals the Dunlop products having all gone to SMT, they don't care about the bottom plate height spec, they only have a minimum. As a side note, though all the Dunlop/VOX (the VOX is made by Dunlop) shells have the same casting numbers, but I suspect are made in different factory's, it's evident that the bottom plate surface is actually "milled" flat and different factory's are milling that height at different spec.

I noticed ya dumped the Bob Sweet vactrol speed pot thing, good move. I can see using it in a 1590BB shoe-horn build, but really no need for it in a wah shell since a normal 100k dual log works fine. It was innovative back in 2002 no doubt, when he developed the (then un-named) Mojo Vibe and it was harder to source Alpha rev-log pots, but again no need for it in a wah shell.

Hopefully offering up these tips will help you get it right while the others are debugging the new project. I don't have time to etch and build one myself but these observations may help ya out.

Peace-out.


{Edit} BTW, I forgot to say, kudo's for bringing back discrete darlington pairs. Your builders will be appreciating that when trying to achieve the natural/vintage univibe tone/throb.

[R.G.]

I noticed you moved the light chamber even farther back (towards heel of pedal) which makes the pipe-cap dimension even more critcal,

It doesn't use a pipe cap, necessarily. Not an issue. Pipe caps are OK, but the harder they are to adapt, the less interesting they are. Innovate - find something else. The world is full of possibilities.

but I suppose evey freebie project needs an issue or two for the builder to deal with (only fair really).

Anything to belittle and FUD a free project, right?

The further back you go the less available overall height the pipe-cap can be, while the inside bulb height restricion remains the same, so wiggle room diminishes,

Don't need a pipe cap. Not an issue. The idea of a pipe cap becomes a functional fixation if you let it. Hey if you're stuck on pipe caps, use a PVC pipe cap cut down to size. They're already bright white inside, and much, much easier to cut to height. Hacksaw blade and a height spacer or even just coarse sandpaper should work fine, and much less work and equipment than a metal cap and a lathe. Think, Brad, think.

When I saw the v-reg there it brought the clearance thing up once again, if it's a TO-220 type you may have to instruct your builders to bend it over or whatever to keep it from hitting the bottom plate of the wah shell.

Yep. When things don't fit, you have to make them. Doh! They aren't my builders - they're intelligent, thinking human beings who have some technical smarts on their own.

I printed your layout from the PDF and taped onto one of my un-populated Vibe-Baby boards and installed it into my (Dunlop) test-shell which I keep handy, and the area where you have your v-reg (IC1?) has about about 17mm height space from board to bottom plate, a TO-220 is about 20mm high so you will have to advise using the 78Lxx there or again advise your builders to bend a TO-220 over a bit to fit without comming in contact with the back cover plate.  

I finally got time to mess with it, taped the paper print on cardboard, measured, and noted that. Changed the pinout; both TO-220 and 92 work, but a builder can choose.

Probably sounds to you like nit-picking

It is.    And to think I deliberately held off on posting this for over a year primarily because you told me you were in negotiations with a major maker of pedals to buy your stuff. I didn't want to muck up your deal. Then months ago I asked about the status of that and you said to go ahead and post it. Sigh. I'm just a sentimental old softie. I probably won't make that mistake again.

but a wah-shell project, unlike other projects, isn't really one that can be done from the computer desk.

... delicately drawing the implication that it was all done in a computer, with no recourse to the real world. Sorry, no cigar. I *did* do the first few iterations in my head and on the screen. That means I didn't have to go build the first few and find out they didn't work, like:

Here's a pic of my rev-1 Vibe-Baby boards which discovered these clearance problems:
(I'm on rev-7 now, lots'a changes over the years)

If more thought and analysis had gone into the rev-1, you might not have to be at rev 7. Just a thought. You might want to do more thinking and less manual hacking. Might save you some time. Beyond that, use of computers to do the first few drafts can, as computers always do, let you make more mistakes, much more quickly. 

Because of the unique parameters of the wah-shell (other than board outline) one really should physically build/test (and rebuild) to get things to fit the enclosure properly, paying particular attention to the restrictions (diminishing height) as you approach the rear of the pedal will become evident as your build proceeds.
(been there, done that, and pioneered the t-shirt!)

Sorry you had to put so much hacking in. It eats a lot of time and makes for a very expensive T-shirt. You finally notice that there is no "the wah shell". It's a variable. Cope with it.

those... caps .. hit the bottom plate
... boards that were the size of the old wah PBC like you did on your UVCIS rev-1 layout,
...I realized there was much more available space (as you did a few posts back)
...I got out the file and trimmed a bit but wasn't happy
...(metal work)
...the shells are not all the same
...Dunlop and the VOX have different heights
...they are different from shell to shell of the same type
...no FUD just the facts ma'am.
...noticed ya dumped the Bob Sweet vactrol speed pot thing
...again no need for it in a wah shell.
...discrete darlington pairs... natural/vintage univibe tone/throb.

I'm surprised you didn't imply that since the UVICS has not been touched by angels, it must be the work of the devil. 

Hopefully offering up these tips will help you get it right while the others are debugging the new project. I don't have time to etch and build one myself but these observations may help ya out.

It's pretty funny watching this, actually. You'll do or say anything to carp about the details, imply that it's nothing new, it's all been done elsewhere by someone else long ago and far away, someone else did it first or better, there are things that are missing, or wrong.

Thanks but your "help" won't be necessary. You're putting rather a lot of effort into this, for some reason. 

[RedHouse]

A friend dropped by my shop a little while ago with his digital camera, so I thought I'd snap a couple pics of what I was talking about.
(the wife has my camera at work right now)  

Here is an off-the shelf copper pipe cap (light shield) with your UVICS-1 and UVICS-2 layouts, as you can see both height and location are an issue:



and specialy with the TO-220 v-reg on UVICS-2:



Hope this helps,

[wavley]

May I just chime in here and say that most of us aren't idiots, we're diy'ers and most of us are perfectly capable of manufacturing a suitable light shield and/or bending leads and any further discussion of this is pretty much a waste of time.  I've been following this project because I have an empty wah shell that is just begging for a project like this.

Any further bickering on this subject is a waste of time, you've made your point.  Now can we just get on with building something cool.

No offense though.  We cool? 

[Brymus]

So 30 seconds is all the time you heated pcb? Any longer? What was the iron temp?
Your pcb turned out so good!

Yeah 30 seconds on high/linen (1-1000,ect)
Not sure about iron temp,but its worth noting that my garage is seriously 110 degrees (or more),
That high an ambient temp probably plays a factor.

Thanks for the kind words all !! 

@ RG
Are you doing a BOM soon ?
I think by giving the exact cap dimensions,(that post answered quite a few questions) I can get those ordered.
I should have an AC wart in my wart box that will work.

Now the dumb questions:
Is there a Mouser photocell that is recomended,or can I just match 4 from Radio Shack ?
Is there a recomended transister and darlington ?
I have 3904,5088,5089,MPSa13 on hand. (and a few others)

I am really excited about this build ,been wanting this pedal for awhile. 
I think I have 95% of the parts already too.

[GP]

Any further bickering on this subject is a waste of time, you've made your point.  Now can we just get on with building something cool.

No offense though.  We cool? 

yeah... we're all feelin' your love Redhouse

thanks for your time... those billions of people who aren't as clever as you will no doubt appreciate your self-sacrifice at posting the solutions

[jimmybjj]

May I just chime in here and say that most of us aren't idiots, we're diy'ers and most of us are perfectly capable of manufacturing a suitable light shield and/or bending leads and any further discussion of this is pretty much a waste of time.  I've been following this project because I have an empty wah shell that is just begging for a project like this.

Any further bickering on this subject is a waste of time, you've made your point.  Now can we just get on with building something cool.

No offense though.  We cool? 

+1

[defaced]

Its cool guys, this is just his style. I've seen it on a couple of forums.

[R.G.]

Are you doing a BOM soon ?

I need to check it again, but I'll get it posted tomorrow morning. I had to do some last minute testing of some stuff before we commit to volume manufacturing.

I think by giving the exact cap dimensions,(that post answered quite a few questions) I can get those ordered.
I should have an AC wart in my wart box that will work.

There is another option I didn't mention. If you can get 10mm diameter caps but can't get them 12mm tall or less, get 10mm diameter but longer and lay down two of them along the rows where caps would go.

Is there a Mouser photocell that is recomended,or can I just match 4 from Radio Shack ?

Photocells and the lamp is usually where people spend a lot of fretting. I had good luck with Radio Shack stuff - a decade ago! I'd recommend  Small Bear now.

Is there a recomended transister and darlington ?

For everything but the lamp driver, most high gain signal NPNs will work For Q1, I like 2N5088. I've built them entirely out of 2N3904 and 2N5088, as well as the "original" 2SC828. There was another one for the front end in the originals, but I have listened to the same box with different transistors and can't hear the difference.

For Q11/Q12, an integrated darlington makes for a more consistent and better performing LFO because the gain stays high in the first transistor at the very low currents at which it works. MPSA13/14, and many others should work fine. There are other mods for this; the higher impedance of the Q11 position, the wider the LFO range. A J201 works well in the Q11 position because of its very low Vgson. It's worth some tinkering.

For Q13, I like MPSW45 and some of the Zetex 1W darlingtons. If you get one for Q13, get two and use the second one for Q11/12 instead of two normal bipolars.

I have 3904,5088,5089,MPSa13 on hand. (and a few others)

Doh! Shoulda read further before replying. If you have those on hand, use 5088s for signal transistors, MPSA13 for Q11/Q12 and Q13.

[Brymus]

Hey thanks RG

So I have everything (if Radio Shack has a few more LDRs) except the 7815. (I have several LM317 though)
Thats using a Radio Shack bulb,LDRs and dual 100k pot.

I was looking at mouser's caps by size and in 10mm x 12.5mm there is a huge selection of caps.
After checking ,I have enough caps the right size for this, I was already thinking of laying down 2 x 1000 uf for the filter caps.
There is plenty of space either way though.

If your sure the part numbers on the UNVICS2 layout ,match the schematic I could get this populated and tested this weekend.
After reading the technology of the Univibe this afternoon,I would like to implement a couple of the proposed mods.
The stereo mod,the phase trimmer,and definetly unity gain.

[R.G.]

If your sure the part numbers on the UNVICS2 layout ,match the schematic I could get this populated and tested this weekend.
After reading the technology of the Univibe this afternoon,I would like to implement a couple of the proposed mods.
The stereo mod,the phase trimmer,and definetly unity gain.

Let's just be sure. I added the schemo and BOM as well as some notes in the project file at GEO.

Unity gain is just a change to two resistor values from the stock values. The phaser trimmer spot is on the PCB, or you can use an external pot, trim, and then solder in resistors. Stereo is not on the PCB, and may not be all that useful on stage, though it sounds great for solo practice. It's hard for an audience to hear the subtlety.

One thing you might want to consider is the high-impedance input. I posted that somewhere in this forum.

[phector2004]

Thanks for getting back to this project, R.G.!

I remember reading about this a while back... I actually postponed building a Univibe until a drop-in PCB came out. Removing the need to mod the shell for a dual-gang pot is very nice as well
What's your suggested way of getting UVICS-1 boards? I'm assuming they're too hard to etch... Will they be offered by one of the DIY stores?

Cheers,

Phil

[R.G.]

I remember reading about this a while back... I actually postponed building a Univibe until a drop-in PCB came out. Removing the need to mod the shell for a dual-gang pot is very nice as well
What's your suggested way of getting UVICS-1 boards? I'm assuming they're too hard to etch... Will they be offered by one of the DIY stores?

UVICS-1 was an exercise in how small it could get. I changed the PCB ground rules to thin lines and tight spacing, so it's really beyond typical toner transfer skills.  It should work fine for presensitized board and optical methods, though.

If you can wait just a bit, let me get some thought done on it. I wanted to put the single-pot option in it, but just didn't have the space the way the UVICS-2 went. I'm thinking a baby board to do the 9V power and the single pot change added onto the UVICS-2. This would be done to toner-transfer spacings as well.

[Derringer]

May I just chime in here and say that most of us aren't idiots, we're diy'ers and most of us are perfectly capable of manufacturing a suitable light shield and/or bending leads and any further discussion of this is pretty much a waste of time.  I've been following this project because I have an empty wah shell that is just begging for a project like this.

Any further bickering on this subject is a waste of time, you've made your point.  Now can we just get on with building something cool.

No offense though.  We cool? 

So Brad .... since you know so so much about how to do this right .... where's your layout/BOM/instructions for us to build from?

O I C .... it costs $160 bucks and all we get to do is solder in the connections ... thanks I guess ... all that other etching and parts soldering looks to hard for me

[RedHouse]

No Derringer sorry, I don't have a public wah-shell vibe (freebie) project for ya, never offered a layout or etched and drilled boards for my Vibe-Baby because my customers are musicians (not the DIY community) say what you like but it doesn't make much sense to hand etch/drill (120 odd holes) then a guy expects to buy it for $12 (and feels slighted if you don't offer) oh sure I might some day when I do some fab house runs but for now and what with the economy down, the Forum-Vibe is my only freebie offering, did you have a vibe project layout to offer-up?.

Anyway, it's all good and yes I can feel the love, kum-by-ya, and peace out.   

[Derringer]

what I implied, but didn't ask as clearly as I should have is "where is your wah-shell-vibe PCB transfer"

I don't have a public wah-shell vibe (freebie) project

thank you for the forumvibe

but ...

I can feel the love, kum-by-ya, and peace out.  

and I'm done

[Brymus]

OK back from Rat Shack
I have everything now except the 78L15  (they had a 7812 I picked up)
The dual 100k from RS wont work for the treadle but will for testing.

Anyway band practice next,maybe tonight I can start populating the board.

For the discreet darlingtons ,I am a little confused ...
Do I use a 2N3904 and 2N5088 together or two 5088's together ?
Does it make a difference ?