New project: Eh Polyphase

[Zero the hero]

Hi folks, I posted a new complete project, the Electro-Harmonix Polyphase.
The layout and PCB have been done by Nelson, so... THANK YOU!
Nelson has built and verified the circuit  (please, tell me ifI forgot something in the article, I'll add any suggestion up!).

[nosamiam]

Thanks for your contribution!  Where would I find it?

[Dave_B]

Thanks for your contribution!  Where would I find it?

Allow me, Alex.   

Click on the oranges, nosamiam.

[jrc4558]

I said it before, and I'll say it again. AY KARAMBA!!! (c) Simpsons

[Marcos - Munky]

Wow, thanks a lot. Hope I can find the parts I'm missing to build this thing.

[Zero the hero]

Allow me, Alex.   

Click on the oranges, nosamiam.

   

[Ry]

What was used to create the PDF file?  All of the text appears as blocks to me.


Thx

[lowstar]

if i remember right, this was the layout that gave nelson headaches because of a ticking problem, did you overcome the obstacles ?

cheers,
lowstar

[Dave_B]

What was used to create the PDF file?  All of the text appears as blocks to me.

What reader are you using, Ry?  I was able to open it in Acrobat Reader V5 and V7.

[Ry]

I'm using the Preview function of OSx, which I thought was up to date.  I will have to look into acrobat.

thx!

[Zero the hero]

Ry, I had the same problem when using Preview (MacOsX 10.3.9 on Powerbook G3), but I solved opening the doc with Acrobat 5 (works with os9 too!).
I should add a couple of lines on the project page.

[Zero the hero]

if i remember right, this was the layout that gave nelson headaches because of a ticking problem, did you overcome the obstacles ?

cheers,
lowstar

We have to ask Nelson, since he built this circuit (at present time, I have no time!!!)

[lowstar]

goodie goodie 

[nelson]

if i remember right, this was the layout that gave nelson headaches because of a ticking problem, did you overcome the obstacles ?

cheers,
lowstar

It was an old layout that gave me ticking problems. This is the improved version with extensive decoupling, larger ground planes, changing of grounding scheme and putting v+ and ground traces between any adjacant signal and LFO traces.

I am confident this layout shouldnt tick. I havent built this particular layout, it was the old one I released to a few people. The layout will work though, as its just a tweak of the verified layout.

Anyway, Enjoy.

Please submit build reports.

Nelson

[nelson]

Alex

A regulated power supply isnt needed, it has an onboard 15v regulator.

all it needs is an 18v supply, I recommend an EH 18v power supply, bear in mind they are positive tip.


Other than that, the text is fine.

[nelson]

Suggestions for possible mods:

A depth pot could be added Leading from point C on the board wired as a voltage divider.

"univibing" the phase stages. 470pf, 4700pf and 0.001 caps replacing some of the 0.01uf caps.

Vibrato switch by lifting 27K mixing resistor. Or even a mix of wet/dry with a pot.


Sure there are more.

Any suggestions?

[RaceDriver205]

Cool, all you have to do now is work out why the Bad Stone layout doesnt work 

[nelson]

Cool, all you have to do now is work out why the Bad Stone layout doesnt work 

I had sweet FA to do with the Bad stone. Also, the layout works AFAIK many people have built it without problems, I know some people have problems with the LFO though.

Build this one instead 

Its the best phaser I have ever used.

[RaceDriver205]

Yeah, that oscillator hates my guts. (And i meant Zero should fix it)
This envelope control - does it alter the rate or depth of oscillation? How 'strong'/phsychedelic is the phasing?

[Zero the hero]

I've checked the BadStone layout everytime someone said that the LFO was not working.
And everything seemed ok...

Here's a sample of the Polyphase driven by a Rhodes:
http://www.fenderrhodes.com/cgi-bin/products-display?id=5