Hi All,

For this moths FX-X Submission over at DIYstompboxes.com, I've gutted a broken Radio/Alarm Clock and have been experimenting with
the TA7613 that it contained. (an on-chip AM/FM radio with class-B power amp section)
Right now, it directly drives an 8Ohm speaker load, hand am still figuring out how to get it down to signal level. Tacking on a regular master volume drastically changes the way the effect sounds which is not cool.

Any suggestions in adding mastervolume are greatly appreciated!
Schem as below, TA7613 Datasheet found at:
http://www.anyplace.nl/pics/diy/TA7613AP%20datasheet.pdf

Oh yeah... It sounds quite unique!!! the distorion is BIG and a little sizzling but controlled. (very AM/FM'y :^)
Turning "beep" al the way up makes it a nasty oscillating fuzz with "bucket" acting as a kind of gate.
The cool thing is the gate (bucket) is VERY controlled and sensitive which is maybe why the volume controls
I've tried dont work. (because of the network "bucket"->"beep"->ground in the schem)

Cheers!

really cool stuff colin!
I'll be building a PU again in the near future as part of a bigger multi noisemaker design, and this looks just like what I was thinking about.
I'm currently working on an improved LM567 based noisemaker
(a revised "noise 567" hemmo circuit)
And just yesterday I wondered how I could wire it into a PU...  
Anyway, thanks for keeping the PU up to date!

Just wanted to let you know I subbed the 47k resistor+5k lin. pot with a 50k log pot and I think it's an improvement on all accounts.
The more "starved" tones can be brought up to "band cutting" volume levels, as well as strange but pleasant alleterations in the circuits behavior...
setting "gate" down and turning up the "starve" pot fully somehow gives an extreme gated effect where only attack is getting through in a good way.
(varies with type of  input though, didn't work that well on turntables...)
Also the distortion is brighter at low levels and "darkens" as volume increases. interesting stuff... I've toyed around with the PU and brought it to various musicians (noise related music & some expirimental DJ's) for testing/opinions and they agreed the 50k pot was an improvement.
Personal tastes apply though, since most people I hang out with tend to like Fender Blenders, Moog Ringmodulators, Oscillating Digitech PDS loopers, etc...

I'll probably make a footcontrolled version with selection knob for either starve/freq/feedback mix to be foot controlled.

Thanks for such a wonderfull design Colin!

LOL Solarpower! would be cool if it ran off the stage lights...
Kinda like a powersupply version of a Photocoupler.

just finished building a mosfet booster for my telecaster.
measures 3x8 holes and packs some serious punch!
Finally something small enough to put in my teley's belly...  




I don't know why but I just love to work in tight spaces...

Well last night I put in a 500k log pot and bypassed the 47k resistor, not only was it uncontroleabley loud...    , but my bypass led would stay on all the time too.
(I used the 2n3904 with a resistor to light the led.)
I just replaced the 500k pot for a 25k lin and brought the resistor down to 15k, works good so far. Goes loud a bit too quickly, hence the liniar versus log taper, so I'll have to order a 50k log anyway and see how that works.
I'm not aiming for fidelty by the way, that's why I wanted a bit more output so the "starved" distortions could be brought up to band cutting volumes.
Anyway, I'm happy now!
I am thinking of building another one with some "improvements"... I want to have a seperate output volume control for the "osc" switch as well as mayebe a boost in front..

you mean audio as in logaritmic or as in value?
like a 50k log or 500k log... I'm not that bright obviously...  
I'm poking around in my SK-1 at the moment...

Say Colin, if I lower the 47k resistor at the output to say 30k and use a 10k pot for volume, would it increase volume output?
I mean It's no problem building a boost after it, but I recon this would be a far more simple way of getting more output volume if it works like i think it does...

Since I work in Hollands biggest Music store I brought the PU down to the shop for a spin... I happen to have quite a few noise lovers as collegues and  the PU (peehew! pun intended) got extensively abused! based on a little hour of playing with it at fairly loud volume since I've build it I do have some ideas as to what I'm going to modify.
First I'm going to put a booster after it (i.o.w. active volume stage) I found out that some off the "starved settings" could use a boost afterwards to get them to stand out. Second I'm going to put a secondary volume control on the "osc" footswitch so that, when oscilation is achieved it switches to a second volume pot so you can match relative output level with your "normal gain" sound. I think it can be quite usefull into tapping into some more potential...

Anyway, get back to that! :^)

Hmmm I hadn't thought of using IC based cicuit bends yet... is that difficult
(i'm still basically a noob in designing circuits from scratch) but I'm willing to learn!

I totally took the SK-1 apart to see where I can make room for certain components.
I've allready started poking around a bit, found some interesting points but nothing too special...

Allright, here's the deal..

I'm finally getting geared up to seriously circuit bend my SK-1.
I plan to document anything interesting and try out various ideas
wich is why I made this thread.
First are there any good bends that any of you are willing to share?
(pointed out specifically on the PCB)
Second, I want to look at some less obvious bending methods if possible,
I've allready bought a six position 2 pole rotary switch to re-rout certain bend-points as well as photo resistors (possibly used as a "mod wheel" setup with a led) some pot's, switches, etc...

I'm interested in discussing possible use of Capacitors/led's/diodes/etc.. in the bend circuits, experience with multipoint bends (3 or more connections) as well as encorporating one or some effects into the design (namely a fuzz and possibly a cheap delay...) I'll be moving the speaker outside of the enclosure so it will have a decent amount of room available.
(I'd like to keep everything onboard)


Let's get wild!

Well, I finally boxed it up this evening... pics are at: http://http://www.anyplace.nl/pu
No soundclips yet, but it sounds absolutely fantastic!  
I'm really perfectly happy with how it sounds at the moment, It goes plenty Loud, even with my tele. (although I haven't tried it live yet)
So I think I'll leave the buffers/boosters for a while and see if it holds up.
I only need to change out the osc. footswitch, I put in Alpha's but one of them was a momentary so I've put a a blue 3PDT in it for now.
The normal overdrive sounds are great with my telecaster, good note definition and clear yet dirty... A bit like the expandora overdrive (not exactly, but it comes close enough) Got some pretty wild synthy sounds out of it allready, I especially like it starved to death...

I also have a Fuzz factory a Foxx Tone Machine (also homebrew) a Zoom Ultra Fuzz Russian Big Muff etc... and this one definatly sits on it's own!
Watch out for the ever expanding Fuzzy Army of doom!
(a friend of mine and I are thinking about starting a band with only fuzzes as effects)

Anyway, Thanks Colin! great box, should have build it long ago allready!
Now on to finally circuit bending that damn SK-1 that's been lying around for ages... Mayebe I'll build a second PU and stick it in!
I've been thinking about putting some extra circuits into the SK-1 anyway, got some cool idea's? (I'll start a new topic soon in the circuit bend erea.)

Hmmm, any other booster/buffer that would achieve simillar results as a microamp without the parts count?
I've got a LPB2 laying around anyway so I'll just stick it in front/end and see if I like the results..

( forgot to mention, whythisreason? = any on GG forum)

I don't know if I've got enough room for two MXr Micro-amps
on this board, besides I've got the parts for an LPB2 in abundance.
How would one be wired in for the gain part though?
Just stick it in place between the 1st and 8th pin on the LM386?
I'll post a follow up later, got some visitors...

PS: got a Zoom G7.1 to review for a magazine, cool stuff!

I've just finished up a PU as well!...

It fired up 1st time so the schematic is O.k.
Wicked sounds! so much good settings to chooce from.
I made some clips wich I will post later. (as well as pics)
I am thinking of building a booster (LPB2) in front of it,
so I can beef up the tele.
Or would a normal buffer work better?
I've build it on 15X15 holes prefboard with some room to spare...  
Mayebe I'll add a photo resistor control to the "freq" pot!
Any ideas for the volume stage? better yet, Colin... would you have some usefull stuff on what's in that "mega" PU that I wear on my T-shirt...

Anyway, I'll post some stuff when I get to it.