Keio Synthesizer Traveler

[digi2t]

Alrighty then...

Seems me and the boys have gone on an obsure, weirdo, messed-up, wah-type effects spree of late. What do you know, I come across this is my travels;





Never heard of it, but info points to Jacques Singing Geisha as a modern day equivalent;



It's a pity, the Youtube video of the Geisha seems pretty cool, but personally, I don't think I would drop 300$ on this pedal (see EBay). Even if it is a "no longer in production - collectable - bla bla bla" pedal.

BUT WAIT!!!, a little more digging turns up this;
www.dirk-hendrik.com/temp/keio_synthesizer_traveler.pdf

So what say you, kind people? Has anyone ever had this sucker underfoot? Is it worth the time? Is a new vero in order here?

Let me know 

[theehman]

There's a thread at the "other" forum.

[digi2t]

Alright, here we go...

Vero layout;


and the schem;


WARNING!!! THE PINOUTS ON THE LAYOUT ARE NOT DRAWN USING THE ORIGINAL TRANSISTOR PINOUTS. I DREW IT FOR E-B-C, WHEREAS THE ORIGINALS ARE E-C-B. IF YOU DO USE ORIGINAL TRANNIES, WATCH YOU PINOUT!!!

I didn't feel like drawing in all the off board stuff. The schem is easy enough to follow.

Note that C10 is drawn as an electro in the schem, but no voltage is supplied. Might be a typo, although 0.33uF electros are available. I'm no EE, so I don't know what difference an electro, or a chicklet will make here. Use your own judgement.

According to the datasheet I found, the "r" suffix on the 2SC644R means an hFe of between 180 and 360. I might try some BC108's or 2N2905A's in here. A BC212 might do for the PNP. I've swapped out R8 and R31 for 10K trimmer for bias adjustment. All in all, could be an interesting platform.

If anyone puts one together before me, drop me a line. I'm between houses right now, so I'm limited to daydreaming vero's right now  . Enjoy!

[pinkjimiphoton]

you know i'm on this like white on rice, don't ya??


btw ehman...the "other" forum is down.

[digi2t]

UPDATE!!!

There seems to be some confusion over at the "other forum" regarding resistor values between the schematic, and this PCB layout;



Well, thanks to mig27, who not only has one for sale on Ebay at the moment, but provided a FANTASTIC gutshot, I may be able to clear up some points. According to the picture, I've changed the following on the vero;
-R13 and R14 are switched. In the wrong spots on the schematic.
-R1 is a 100K, NOT a 1M.
-R26 is a 2.2K, NOT a 47K.
The colors and positions seem to correspond to the picture.

Also, C10 seems to be a polarized cap, resin tantalum is my bet. Q5 doesn't look like it's a 2SC644R either, it doesn't resemble the others in the picture, so my hunch is that 2SC828 is correct.

Here is the gutshot;


Plus a bonus for the pots and wiring;


And, without further ado, the updated vero;


As always, if anyone gets this sucker together before me, let me know. This baby is high up on my "to do" list. Thanks again to mig27 

[pinkjimiphoton]

white on rice, bro....

soon as i can afford the parts i don't have yet, this puppy's on the big list of stuff to do asap!

thanks!!   

[digi2t]

No problemo. Just got a message from mig27, he may be able to provide some more nice gutshots. I also asked him if he could verify the tranny numbers as well.

Seems to be a righteous dude.

Stay tuned....

[oskar]

Thank you!

I met this guy some ten years ago who talked about this pedal. Back then I couldn't find anything in searches.
b.t.w. Keio later changed name to Korg.

[mig27]

Hey guys,

Keio Synth Traveler owner here.
Nice to see all this activity!
I'll take more gut shots later today and will post them here.

Actually I'm planning on cloning this thing for use in my modular synth, so I'm keen on giving you as much info as possible.

Stay tuned.


Michael

[digi2t]

Thanks Michael!!

I've also put all this info into the Gallery under "Dino's Stuff".

As I mentioned in the other thread, if you could get the numbers/letters off the transistors as well, that would be great.

I get the feeling, from looking at the circuit, that one could almost sub a lot of different circuits or transistors in the fuzz section. Almost tailor it to your liking. Lots of possibilities here 

Cheers,
Dino

[oskar]

Hey guys,

Keio Synth Traveler owner here.

Sounds man!

[digi2t]

Yo Michael!!!!

Important... could you also check the taper of the pedal pots (100K dual gang)? Are they audio, linear, reverse, what?

Thanks,
Dino

And maybe an audio clip for Oskar... he's starting to leave a puddle when he stops moving  .

[mig27]

Ok, will do

[mig27]

Ok guys, here come the pics.

Let's start with a 360° series, covering all angles of the PCB:















The pots:



Total view:



The dual gang pot is labelled YG30S A 100kOhm * 2

Transistors:



Oh, and I found the manual:





And in case you want you want to bid on my auction:
eBay item # 270808168627
Auction ends this Sunday.

Cheers, good luck with your cloning everyone!


Michael

[digi2t]

Michael, you rock man!!

The only way it would be better would be if I was right in your living room, looking at it myself.

The "536 FS" tranny may well be a 2SC536, the "F" denoting an hFe of 160-320 (according to the datasheet I found on the net). The dual gang is "A", so that's a Log pot. I think it's time to start breadboarding.

And that manual, is just killer!! We need a "rolling with laughter" smiley!!

Thanks a ton Michael!!
Dino

C'mon, everyone, give the man a hand!!  

[pinkjimiphoton]

righteous michael!

hey dino, did you try calling me a couple days ago? long story, but lately i've had some phone issues..

[digi2t]

Been doing some research.

Since 2SC644R's are real hard to come by, I've found that BC108's are a decent match. Like the 644's, the 108's also come in 3 flavors, no letter, B, and C. 108's without any letter are unsorted, could be anywhere between hFe 110-800

108= hFe 110-800
B= hFe 200-450
C= hFe 420-800

Since the 2SC644R is spec'd at 180-360, I figure BC108B should be just about right. Voltages and currents look right as well. I've used 108's and 109's in fuzz circuits, and they sound great. Not too hard to come by either. I tried digging up some BC239's but they're pretty pricey. They're a good match as well, but hard to come by.

In a pinch BC182/3/4, or BC549 should work as well

[digi2t]

Weirdness of weirdness!

Found one on sale on EBay, with gutshot posted. Check out the board;



as compared to;



AN INDUCTOR!... SERIOUSLY? WOW! I really wonder which version came first. The inductor version serial number is 720147, while mig27's (the vero version) is 720121. Korg made a change somewhere between here. A lot less wiring too. Crazy! Sent a message to the seller, maybe he can help decode it for us before it sells.

[pinkjimiphoton]

if it sounds like the singing geisha, it's gonna suck...that thing is atonal and unmusical...




you know...


PERFECT.

[digi2t]

DAMN!!!! Just saw a video of the Snarling Dogs Mold Spore Wah.

Blew my socks off at 50 paces man.

OUUUFFF!! On my wish list (or should I say scroll!)