Phonic Taxidermist question

Jaytee · September 19, 2016, 04:42:54 PM

Doesn't seem to be a specified place for discussion on this, so I figure here is as good as anywhere.

Anyway, I fucked up when ordering parts and got 47ohm instead of 4.7ohm for R33 (third thing on the parts list, off to a bad start, eh?). I have some 10ohm resistors handy, can anyone wager a guess if this would be ok, or should I place another parts order?

Circuitbenders · September 20, 2016, 02:08:19 AM

I'm not 100% sure why R33 is there, but its on all the datasheets so i guess its important. It might be something to do with protecting the RAM on startup, in which case i guess 10ohm might well work fine.
You can always change it for a 4R7 if the delay is behaving strangely.

Jaytee · September 20, 2016, 04:23:39 PM

Thanks for the quick response. It didn't seem like a particular value-sensitive part to me either, but figured I'd ask just in case I was missing something obvious (which happens a lot). Soldered in the 10R, still working through the rest of the BOM. Hopefully I can test things out later this week, I'll report back whenever I do.

Jaytee · September 20, 2016, 05:40:43 PM

Ok, last time I ever order parts at midnight. I ended up getting a dual pot with detent because I wasn't paying attention. I could tell immediately that this would drive me nuts, and upon careful disassembly, I couldn't see an easy way to remove the detent. So what's one more Tayda order? I threw in some 4R7 resistors since I may as well just do it right.

Ah well. Excited to finally get this thing finished, whenever parts decide to arrive! I think I'm going to install it in a Casio SK-8 that's getting the semi-modular treatment.

Circuitbenders · September 21, 2016, 12:56:28 AM

A centre detent pot would be very annoying on the distort knob.

Theres a whole thread about the Phonic Taxidermist on the Muffwigglers site
https://www.muffwiggler.com/forum/viewtopic.php?t=159940

davelybob · February 14, 2017, 10:25:42 PM

Quote from: Circuitbenders on September 21, 2016, 12:56:28 AM
A centre detent pot would be very annoying on the distort knob.

Center detent pots are effing annoying on pretty much everything. Screwed up and bought those for 1) the LTC on my SA-21, 2) like half the pots on my 4ms Stereo Paneur build. Dumb dumb dumb.

BTW, never did get my Taxidermist working. You can hear the effect on the output, but I can't get any input into it. I know I messed up one of the solder pads on the line inputs, straight up melted it off the board (probably should find a smaller wattage soldering iron), but now I've got the jack going to the mic inputs and no signal is getting through there either. One of the caps I got (can't remember off the top of my head at work if it was C1 or C15) didn't fit very well, pretty much had to shoehorn it into the holes, but I have replacements so I guess I am going to try that first, if that doesn't fix it, I'm thinking I should look at the LM358 right there, does that sound about right? Or do you have any other pointers?

boneless · January 14, 2019, 07:33:02 PM

Hope you've got your PT working by now...

LOL! 2 years on and I'm finally getting round to building mine!

Firstly a power supply question:

I'm putting it in my eurorack so should I bother with the voltage regulator to take 12V does to 9V? I'm assuming my Bastl marton case provides 'clean and stable' power, but I've never checked.

And secondly for R27 I only have 16k. I could kludge 10K+5K in series, or use 16K.

It looks like R27 goes to ground from the LM358, but being a being an-electronic-dunderhead, I've no idea what using a different value here will make.

Thanks electronic-nerd-friends!

boneless · January 18, 2019, 02:38:37 PM

All built with a 15k Resistor and 9v voltage regulator. (see above post)

Delays work fine and sound gritty and good. I don't seem to have any audible frequency chopping though. I can hear it has an subtle effect on the delays, but not on the main voice.

Distortion seems to work fine, and delay and feedback. Frequency pot doesn't seem to do much. I'm guessing that should sweep the 4 bands of chopping?

I might do a demo to see if folk think it's normal...

In the meantime anyone any ideas on where to look on the PCB.

It was a nice clean build apart from the 5v regulator. I accidentally put the 9v one in and couldn't desolder one of the legs out so had to sit it on top. Looks awful, but the power LED lights, so I guess 5v must be getting through. And looking at the schematic, that doesn't seem to effect the chopping circuit.

Thanks!

and

I freaking hate it when it don't work first time!

marilynchaisson · February 05, 2019, 01:46:53 PM

You said the following, "You can hear the effect on the output, but I can't get any input into it. " However, I am not sure what you mean and how this works:)