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Toneczar - Openhaus

PostPosted: 29 Oct 2009, 12:02
by abfackeln
Got this in over the weekend.... fun little pedal.

I was impressed with the build quality, and attention to details. All nuts secured with Loctite (the red stuff), so much so that I couldn't remove the nuts from the in/out jacks, and sheared the collar off of the mid switch, even after using some acetone to loosen them up. All pot leads from the board were braided, not just twisted - wire color coding consistent throughout the pedal and even denoted on the board. Overall the design of the pedal seemed to be well thought out. And all stuffed into a Hammond 1590S. Pedal runs on 18v only (no battery).

The controls - Vol, Gain, treb, mid and bass knobs. Phase, Mode and "mid" switches. The mid knob has a center detent. CCW from the center detent, the knob seems to act like a mid cut, and doesn't appear to be affected by the mid switch. CW from the detent, the mid switch alters the mid frequencies for pres, mid, and hi-mid settings.

The pictures - I included the part names in the topside photo, and they match up to the schematic and parts list.

The schematic - This is UNVERIFIED and a work in progress. I'm not known for my schematic abilities, so hopefully it's readable - I expect corrections will have to be made. All IC's and transistors were sanded down, and colored over with a permanent marker. I was able to "massage" one of the IC's, and could make out "OPA26_4AP", so I'm assuming all 4 IC's are the Burr Brown OPA2604AP. All transistors/orientation in the schematic are incorrect at this point, since I have no idea what they are - there's no way to identify them from looking at them, so I'm hoping some of the members here can help with identification by seeing where/how they are used in the schematic. Once we can determine likely values, I'll update the schematic. All resistors were verified with color bands and a DMM (although some DMM measurements didn't match up in-circuit).

Image

Image

Schematic removed by moderator (it was an older version)

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 29 Oct 2009, 12:08
by soulsonic
Wow, thanks! I didn't expect this one so soon. It's a fun surprise this morning.
:applause:

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 29 Oct 2009, 12:15
by soulsonic
Ok, it's a little jumbled, but it looks like what's happening is that the input stage is going into two cascaded Mu-Amp stages and then to a fairly standard tone control section.


oh, and it looks like the board is from ExpressPCB.

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 29 Oct 2009, 12:38
by borislavgajic
soulsonic wrote:Ok, it's a little jumbled, but it looks like what's happening is that the input stage is going into two cascaded Mu-Amp stages and then to a fairly standard tone control section.


oh, and it looks like the board is from ExpressPCB.



ExpressPCB....becouse of fonts? :thumbsup
I like how this pcb looks....very neat :block:

boris

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 29 Oct 2009, 13:49
by guiddruid
Q1 looks likely to be a linear regulator, not a transistor. Probably 15v?
If you use your meter on diode mode, you should be able to identify the base of each transistor. B-E and B-C should both measure as diodes, polarity of the diodes will tell you if you have a PNP or NPN. Forward voltage will tell you if it's a fancy germanium or not - seems unlikely, but hey...

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 29 Oct 2009, 14:01
by abfackeln
guiddruid wrote:Q1 looks likely to be a linear regulator, not a transistor. Probably 15v?

Likely so.... voltage drops to 15v (14.65v iirc) at the C3/C38 junction. Q1 is also a different size (physically) than the other transistors.

I'll try measuring the transistors this evening....... thanks for the tip.

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 29 Oct 2009, 14:41
by IvIark
Top man! :applause: [smilie=a_goodjob.gif]

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 29 Oct 2009, 16:47
by plugzzzz
will definitely build this one will wait till its verified

how about the dove???

abfackeln your the man!!!!!

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 29 Oct 2009, 17:17
by culturejam
Awwwww yeah. :horsey:

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 29 Oct 2009, 20:39
by SPeter
Thanks a lot abfackeln!
:applause:
Can't wait for verified schematic to build this one!
:D
:horsey:

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 30 Oct 2009, 01:54
by abfackeln
Attempted to measure the transistors..... not sure I have a complete handle on this - first time I've tried to identify unknown components in-circuit.

Here's what I've got (DMM set to diode test):

Q6 - NPN, forward voltage between B-C = 964mV, f.v. between B-E = 973mV. TO-98 package?

Q3, Q4 (metal cans) - NPN (Germanium?), foward voltage between B-C = 221mV, f.v. between B-E = 224mV

Can't get any sort of consistent read on Q2 or Q5.....

Figure Q1 is a voltage regulator like guiddruid suggested, likely a 78L15 or similar?

Maybe I just have no idea what I'm talking about.......


edit: kusi correctly noted that R30 is 1M, not 604R as denoted in the parts list.....

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 30 Oct 2009, 02:57
by soulsonic
been looking at this... it looks like Q3 & Q4 are arranged in a Fuzz Face sort of circuit with Q2 acting as an active load for Q3 in an SRPP sort of way. I'm thinking this helps with temperature stability.

Q5 & Q6 are most likely JFETs and they are arranged in an SRPP way as well.

Interesting!

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 30 Oct 2009, 05:54
by The Rotagilla
I just listened to one of the sound samples from the Toneczar site. While most likely not my cup o' tea, the pedal sounded pretty good. The guy's playing reminded me of early Satriani.

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 30 Oct 2009, 06:21
by perregrintuk
Awesome project, I'm so damend looking forward to the trace!

Thanks man!

Re: Toneczar Openhaus [gutshots and schematic]  [traced]

PostPosted: 30 Oct 2009, 12:20
by kusi
i made a redraw of the circuit for better-reading ;) thanks a lot for your work abfackeln!! :)

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 30 Oct 2009, 12:44
by guiddruid
Link missing from pins 4&2 of the expression pedal? :) Also guess that the LED is connected off-PCB to R18? Much easier to read now, thank you. Any chance you could add the component values to the schem? It makes it easier to read, imho.

Seems a little odd to me that the transistor (distortion?) stages are run from the raw +18V input... why not use the nicely filtered +15?

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 30 Oct 2009, 13:34
by abfackeln
guiddruid wrote:Link missing from pins 4&2 of the expression pedal? :) Also guess that the LED is connected off-PCB to R18? Much easier to read now, thank you. Any chance you could add the component values to the schem? It makes it easier to read, imho.

Seems a little odd to me that the transistor (distortion?) stages are run from the raw +18V input... why not use the nicely filtered +15?

Thanks for the redraw, kusi. I agree it's much easier to read.

As far as the transistors, they are run from the +15v - the confusion is likely from my half-ass schematic. The top side trace in the pcb pic is the +15v feed......

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 30 Oct 2009, 14:14
by cpm
wow
6 opamps for tone shapping, isn't that a little overkill?

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 30 Oct 2009, 19:42
by Whoismarykelly
Why was my post in this thread deleted?

What did you think of the request on the bottom of the pedal that asked people to not post photos of the PCB on the internet?

Re: Toneczar Openhaus [gutshots and schematic]

PostPosted: 30 Oct 2009, 20:08
by abfackeln
Whoismarykelly wrote:Why was my post in this thread deleted?

What did you think of the request on the bottom of the pedal that asked people to not post photos of the PCB on the internet?

It wasn't deleted - one of the mods moved it to the Big Catfight thread. And i posted my response over there.

What does it matter?