photonic juergulator rev 1

[pinkjimiphoton]

hey my friends,
i just wanted to hip you to a quick revision on the juergulator. i finally have a couple days off to mess with the circuit some.
i think i've improved on it... all the same sounds are in it, but it gets a bit more now.
here's the deets... swap out the 50k harmonics pot for a 10k... now the harmonics pot will be more useful, instead of all bunched up near the top, and you'll gain a little more balls. also, it lowers the input impedance significantly and makes the juerg way more friendly to guitar knob tweaking, like a fuzzface.
next up, take the "tweak" (or as i call it now, the "focus") pot and bump it up from 500k to 1 meg. you can go to TWO megs if you want to probably. this will make it much more obvious... almost like a tone or attack control... still subtle, but definitely more noticeable.
you can also try raising the percolate value to 250 or 500k most likely, tho i haven't tried yet.
this one i just finished is built to miro's excellent layout on tagboardeffects.
miro, i can't thank you enough.. really really groovy layout!!
i guess this makes it juergulator rev. 1 if you make the changes.
all pots linear
again, pnp ge russian mn25b, this one's hfe is 62
and a bc547, this time an hfe of 580.
i think we can call it done.
rock on, my brothers and sisters of diy
talk soon
peace
pink jimi photon
ReplyDelete

all the layout , schem demos etc are here.
i had someone trade me a mid 70's epiphone crestwood for the one in the video, this stupid little dano hodad does not do justice to the sound of it.
if you like percs, try this thing out. i think you'll be surprised.



http://www.diystompboxes.com/smfforum/index.php?topic=102861.msg932469#msg932469

miro's layout

http://tagboardeffects.blogspot.com/2013/09/pink-jimi-photons-photonic-juergulator.html

[jdub]

Dude, you are awesome 

[pinkjimiphoton]

all i can say is wait'll you hear this $#i7.

seriously. it's surprising the hell out of me. just boxed the first "official" one, gonna put it to trial by fire at enforced recreation, live on stage tonite.



you can dial in the harmonics/octave with the percolate control, and adjust the contour and slipperyness with the focus control.
the focus adds more high end harmonics as you turn it up.

video to come soon.

[GGBB]

If it sounds better than the original, it must be incredible.

The Guitar FX vero adds a 10K resistor from the Harm pot pin1 to ground and you're changing the pot to 10K, so is that 10K resistor a bad idea now?

Also, you have a 47R and a 100K in series from power in - probably don't need the 47R right?

[pinkjimiphoton]

If it sounds better than the original, it must be incredible.

The Guitar FX vero adds a 10K resistor from the Harm pot pin1 to ground and you're changing the pot to 10K, so is that 10K resistor a bad idea now?

nope, it's good... that just makes it so you can't turn the volume all the way down... or you could omit it. i don't think it would matter much. gives it a load of 20k i guess like that.  i'd imagine tho you could omit it completely.

Also, you have a 47R and a 100K in series from power in - probably don't need the 47R right?

yah, i guess you could leave it out. it's really only there to help quiet the power supply a little. pretty negligible effect i'd imagine. when originally done, this had the 47r resistor in series with the b+ to help smooth the ripple a little, then it had a reverse biased 1n4001 to ground in parallel with a 100u cap, a 560p cap, and then another 1n4001 in series for overvoltage/reverse polarity protection.  you can add it or subtract at will. i generally add that stuff anyways if i'm gonna be running off a wart. that one stupid little resistor can make a huge diff in noise sometimes.

remember, i'm a hack. i take the 10,000 monkeys approach, i'm sure there's stuff that could be improved on this. i mean, i found some huge improvements on it just this morning. so if it doesn't seem necessary, it probably isn't. 47r is pretty negligible and i don't think it adds any mojo whatsoever.

fwiw, the 47u cap is an electro, the rest are chicklets or ceramic. no real difference in tone that i've noticed, maybe just a touch more upper harmonic ring with ceramic. all the resistors are 1/4 watt carbon comp. i think the 470k was a metal film. that's it, no mojo really.

for authentic jimi photon vibe, use an ultraclear blue led with a 10k clr on the + side, and another 10k between switch and ground. no pops, no led noise that way.

seriously thinking about adding the transmission control from my transmission overdrive to this thing to play with the octaves more. i bet it would sound hip to be able to pan between the ge clipper and maybe some led's or bat41's.


[/quote]

[GGBB]

Thanks Jimi.  This is on my list for sure.  I have redrawn the schematic and am almost done with a PCB layout - will post them soon.

[pinkjimiphoton]

thank YOU gord!!!

took it out last nite put it thru it's paces...

the other guitarist took it home to try... he's bringing it back tonite

one of the bass players WANTS IT...

i think you'll diggit!!

[GGBB]

Here are the goods.  I added a power protection/filtering section and a status LED - if there's anybody who doesn't want it then just leave it out or jumper it where necessary.  Pots are board mounted.  Extra grounds and two LED connections depending on how you orient the board and where you want your LED.  Board size is 2.2"x1.7" so it will fit in a 1590B. 

EDIT: You can flip the board vertically and mount the pots component side with the solder side facing down if you like - that's the way I intend to do it.

Schematic:


Layout:


PCB Transfer (300DPI):


NONE of this is verified - use at your own risk - please post problems here and I will correct them.

[pinkjimiphoton]

looks awesome gord!!

[Jdansti]

Nice!  It's on the list!  Thanks!

[Vallhagen]

Brilliant job GGBB.

Just a question: Do you really need both D3 and D4?

***

I played with it a bit during last weekend, and got me a pcb design as well. Doublesided and unverified yet. If its ok (Jimi?) and you like me to, I gladly share it here. Might not be necessary though, with Gords great job done:)

I am still lookin forward very much to build this up!

Cheers

[pinkjimiphoton]

hi bengt, yah, you need the diodes...they're what makes the octaves happen, take 'em out and it's a jerkulator.
i didn't experiment with using silicon, so no idea if more ubiquitous diodes will work well or not, tho i imagine it may be a wee bit louder without them.

i would love to see your layout, too, so please feel free to post away bro!! it's an honor to be able to give something to the community and have the community give something back.

i hope to day in between doc appointments and crap i can video the juerg so you guys can hear it.

did you build this as posted, bengt, or did you try the updates?

[GGBB]

Just a question: Do you really need both D3 and D4?

No - that's the power protection stuff I added.  D3 protects from reverse polarity and D4 protects from over voltage - and I just realized I typoed on that one - should be 1N4739.  I would normally leave out D4 myself, but for those who want extra security I added a place for D4.  You can jumper D3 as well if you don't care about that stuff at all.

[pinkjimiphoton]

whoa, my bad, sorry!!

yah, i usually just use 1n4001's there, 4739 is a better choice. i didn't add them or anything like that on this build, i've found with percs sometimes they don't seem to run right with too much filtering on the power. it's such a weird ass circuit..

[GGBB]

As Jimi said you can also use 1N4001/2/3/... - at D3 for series reverse protection, or jumper D3 and put one at D4 for parallel reverse protection.

[Vallhagen]

i would love to see your layout, too, so please feel free to post away bro!! it's an honor to be able to give something to the community and have the community give something back.

Awrite, here we go:)

As said, this is NOT verified yet. Basically its like your original post Jimi, a small 100p cap added, and I also skipped the two resistors around the Tweak pot.

And as you see, I go with my routine, and use an 1N4001 for pwr polarity protection.

Complete EAGLE project, packed file:
https://dl.dropboxusercontent.com/u/10190945/juergulator/juergulator_Vallhagen_1.rar

High resolution Schematic:
https://dl.dropboxusercontent.com/u/10190945/juergulator/juergulatorSCH300_1.png

Lower resolution schematic:

Board Layout (this is, if wanted, easily tweakable to a onesided layout):


Cheers!

[Vallhagen]

Just a question: Do you really need both D3 and D4?

No - that's the power protection stuff I added.  D3 protects from reverse polarity and D4 protects from over voltage - and I just realized I typoed on that one - should be 1N4739.  I would normally leave out D4 myself, but for those who want extra security I added a place for D4.  You can jumper D3 as well if you don't care about that stuff at all.

Thanx for clearing that out:)

[pinkjimiphoton]

i would love to see your layout, too, so please feel free to post away bro!! it's an honor to be able to give something to the community and have the community give something back.

Awrite, here we go:)

As said, this is NOT verified yet. Basically its like your original post Jimi, a small 100p cap added, and I also skipped the two resistors around the Tweak pot.

And as you see, I go with my routine, and use an 1N4001 for pwr polarity protection.

Complete EAGLE project, packed file:
https://dl.dropboxusercontent.com/u/10190945/juergulator/juergulator_Vallhagen_1.rar

High resolution Schematic:
https://dl.dropboxusercontent.com/u/10190945/juergulator/juergulatorSCH300_1.png

Lower resolution schematic:

Board Layout (this is, if wanted, easily tweakable to a onesided layout):


Cheers!

bengt, you REALLY need the two resistors around the tweak pot. the tweak pot doesn't make a lot of difference without them. seriously. nite and day, bro... you wanna add them back in. definitely. and use the revision values. 1 meg for the tweak pot is a HUGE diff, without them resistors tho, the tweak pot doesn't really do sh*t.

looks great tho!!

EDIT: you need the two resistors, or go to a 2meg pot. the resistors also are important for setting the range of the second gain stage, and prevent you from getting too high or low... too high, and it becomes unstable, too low, and it could become unuseable.

the harmonic pot in this needs to be 10k, not 100

the tweak/focus pot needs to be 1m for best results. i tried a shit load of different value pots, and these two changes are literally HUGE tonally.

i mean, you can build it however you choose, but you won't get the same sound out of it as shown. i started with the 1 meg with no resistors... it's not even the same animal without them on the focus control. try it on the breadboard, i believe you'll find them worthy of inclusion.

the harmonic pot at 10k lets the guitar and fuzz interact way better than any perc/jerk i've tried. huge difference, and the harmonics pot actually works over most of it's range instead of being all bunched up in the last 1/8th turn.

not trying to be a bitch.... just want you guys to try it as envisioned before ya leave stuff out thinking it's unimportant.

by all means, if ya don't like it do what ya choose... but it won't sound the same, that i can 100% guarantee.

[pinkjimiphoton]

also, you may wanna re-visit the pots with the wipers tied to pin 3. i did do that, and it sounded and worked far better as a simple 2 connection variable resistor (particularly on the focus control)

[pinkjimiphoton]

this thing keeps surprising the hell out of me.
i thought it could use a little more volume. i found q2 doesn't matter much.
but q1 sure seems to. and against what i thought would be logical, it is louder/gainier/more distorted the LOWER the hfe of the transistor..
i tried a whole bunch of 'em, the one i stuck with has a gain of maybe 40. much better.

q2 i ended up putting on a switch, one side is the stock with the bc547, the other side an AC176.

MAN... i'm sold. the two are very similar, yet worlds apart.. as expected, the ac is fuzzier sounding, and the bc a bit more strident.
the octave response is different, as is the response of the focus control. with the si, it's almost like a tone control in a way...but with the ge, it's like...
kinda.... controls the sustain, bloom and character of the fuzz.

tomorrow when gineen goes out, i'll shoot some video. i think you guys will approve.

peace