That sounds accurate to me, I'll give it a shot when I get to building this. Hoping to have time to finish up the Theremin I've been slowly putting together as I've acquired the parts this weekend and then I'll probably tackle this next since I already have all the parts.
But now having an issue with the output. Its super low. I tried with a boost circuit, and also a basic preamp circuit (0 knobs) in front and its still quiet. Any ideas?
It is a quite noisy filter so you should get some oscillation at some settings, I believe at the end of the rotation. Sorry, forgot to check the schematic and the switching. I'll get home tomorrow and have a look but I do remember that the switch arrangement looked unconventional/odd)....
hi, I tested this again and Volume Knob worked ( Overall volume still low). I couldn't tell if the Resonance pot was doing anything. D1 and D2 dont light up to bright on the board (not sure if that influences anything)
It is possible that the schematic is buggy but couldn't spot any errors. I think I will compare it to other schematics if I can find any. Not sure if the LEDs should light up since they are part of the voltage reference network. Here is the schematic I'm working from. http://i756.photobucket.com/albums/xx206/storyboards27/Mobile%20Uploads/E9B94169-591E-4021-A7C4-D929F7F7BD6E_zpsdxarmfs2.jpeg
I built a Zvex SHO as a preamp and the pedal seems to work. I used a trimpot as i didnt want to drill a new hole. It works well but has a bit of Grit to the whole circuit. Im getting a friend to come and have a look and see if its the same as what his friend made. I cant seem to tell if the Rate Knob is doing anything though. Volume does what it should and Freq is kind of the amount of grit but cant tell what rate does.
I did notice a volume drop when plugged into the front of the amp so i tacked on a Zvex SHO before the board input to bring the volume up to unity. Thru fx loop it seemed ok
Yep. I had a friend who built this also and put a little boost circuit like the Zvex SHO before it. I used a trimpot in the boost circuit and set it so the pedal was at unity when engaged. That way i didnt have a knob that would be tweaked and need to adjust evetytime
Hey! Just built this, direct from the layout, no changes. I dont seem to have the volume drop issue others are having. Theres is a volume difference between the switch positions but neither are below unity. Im using a JRC13700 though i doubt that makes a difference. Anywho, another verication for you. Works great!
Can also confirm the LFO connects under(or straight to) lug 2 on the freq pot. Gives a real nice phaser/filter type effect. Works best with a 1M LDR. Tested with 0.2m,0.5m,1m,2m,5m and 10m.
Hi, halfway thru making this and I have a noob question: How do I wire the pots? I'm looking at the frequency and resonance pots for example: the Freq 1 and Resonance 1, I would've thought were grounds. And 2 goes to the middle legs of the pots? Except Volume 2 goes direct to the output jack, and then to the 2nd leg of the volume pot? Am I getting this right or am I way off? Thanks so much, your site is awesome!
This should answer most questions. In this case (and many others) the output of the effect doesn't come from the layout but volume pot lug 2. https://tagboardeffects.blogspot.com/2012/02/offboard-wiring.html
Thanks for the response. Does this mean I daisy-chain Volume pot lug 2 to lug 2 of frequency, resonance, and lfo? Also, what then are the off-board wires Resonance 1-3 and so on for then? Also, if lug 1 is ground, I still don't understand the point of Resonance 1.
No, no daisy chaining. Just take Anders' instructions at face-value. "Resonance 1" would connect to that pot's lug 1 etc. Your volume lug 2 becomes your effect output which is connected to your 3PDT switch. The link I added shows the Skreddy method which is pretty standard. I use it most often.
For the "switch" connections (this is another switch, not the foot switch) the DPDT lugs are numbered like this: 1 4 2 5 3 6 You jumper lugs 3 and 4 and that is your effect input. So that is connected to your foot switch input.
Wired everything up accordingly, and as tagboard effects required. All I'm left wondering is, what's the LED+ cable about? Did I miss something with the wiring of the 3pdt status LED or is this unrelated? Is it necessary?
It's connected to the CLR resistor on the board - it's just there to connect to the positive leg of the indicator LED so you don't have to use a resistor offboard. If you have pre-wired LEDs or just don't want to use it, you can just leave it out, no harm.
Thank you, very clean layout !
ReplyDeleteIs it possible to add CV input to this?
ReplyDeleteI have no idea really. But the schematic has an optional LFO input... might be a hint? It should be connected bellow Freq 2 connection at pad C17.
ReplyDeleteThat sounds accurate to me, I'll give it a shot when I get to building this. Hoping to have time to finish up the Theremin I've been slowly putting together as I've acquired the parts this weekend and then I'll probably tackle this next since I already have all the parts.
ReplyDeleteI have all the parts for this except the switch. Is the a way I could use a dpdt on off on?
ReplyDeleteI think you can but the middle position will be out of circuit.
DeleteJust wondering what leg i should solder the LED- to?
ReplyDeleteIt is the bypass LED so it should be soldered to the bypass switch.
DeleteThanks fuzzhead. Fixed the Switch issue.
DeleteBut now having an issue with the output. Its super low. I tried with a boost circuit, and also a basic preamp circuit (0 knobs) in front and its still quiet. Any ideas?
I'll take a closer look tonight...does the Resonance pot acts as it should?
DeleteHow is the Resonance Pot supposed to act?
DeleteIt is a quite noisy filter so you should get some oscillation at some settings, I believe at the end of the rotation.
DeleteSorry, forgot to check the schematic and the switching. I'll get home tomorrow and have a look but I do remember that the switch arrangement looked unconventional/odd)....
hi, I tested this again and Volume Knob worked ( Overall volume still low). I couldn't tell if the Resonance pot was doing anything. D1 and D2 dont light up to bright on the board (not sure if that influences anything)
DeleteIt is possible that the schematic is buggy but couldn't spot any errors. I think I will compare it to other schematics if I can find any. Not sure if the LEDs should light up since they are part of the voltage reference network.
DeleteHere is the schematic I'm working from.
http://i756.photobucket.com/albums/xx206/storyboards27/Mobile%20Uploads/E9B94169-591E-4021-A7C4-D929F7F7BD6E_zpsdxarmfs2.jpeg
I built a Zvex SHO as a preamp and the pedal seems to work. I used a trimpot as i didnt want to drill a new hole. It works well but has a bit of Grit to the whole circuit. Im getting a friend to come and have a look and see if its the same as what his friend made. I cant seem to tell if the Rate Knob is doing anything though. Volume does what it should and Freq is kind of the amount of grit but cant tell what rate does.
ReplyDeleteResonance not rate haha long morning :/
DeleteThis comment has been removed by the author.
DeleteIC Voltages are:
Delete1 - 1.25
2 - 0.01
3 - 2.91
4 - 3.06
5 - 3.28
6 - 0
7 - 3.05
8 - 1.99
9 - 1.99
10 - 3.07
11 - 9.11
12 - 3.07
13 - 3.06
14 - 2.99
15 - 0
16 - 1.25
Can I also confirm the wiring for the DPDT switch. Is it
ReplyDelete1 2
3 4
5 6
Or
1 4
2 5
3 6
Thanks
And which legs engage with part of the circuit?
DeleteI have had another look at this and realised i didnt full make a Cut where needed. I rectified this and The pedal works so I'd say its Verified.
ReplyDeleteFinally! :-)
DeleteThank a lot, tagged.
I did notice a volume drop when plugged into the front of the amp so i tacked on a Zvex SHO before the board input to bring the volume up to unity. Thru fx loop it seemed ok
DeleteHello, same problem with low volume...
DeleteThe solution is only to use a preamp before the Filter ?
Yep. I had a friend who built this also and put a little boost circuit like the Zvex SHO before it. I used a trimpot in the boost circuit and set it so the pedal was at unity when engaged. That way i didnt have a knob that would be tweaked and need to adjust evetytime
DeleteHey! Just built this, direct from the layout, no changes.
ReplyDeleteI dont seem to have the volume drop issue others are having. Theres is a volume difference between the switch positions but neither are below unity. Im using a JRC13700 though i doubt that makes a difference.
Anywho, another verication for you. Works great!
Can also confirm the LFO connects under(or straight to) lug 2 on the freq pot. Gives a real nice phaser/filter type effect. Works best with a 1M LDR. Tested with 0.2m,0.5m,1m,2m,5m and 10m.
ReplyDeleteHi, halfway thru making this and I have a noob question: How do I wire the pots? I'm looking at the frequency and resonance pots for example: the Freq 1 and Resonance 1, I would've thought were grounds. And 2 goes to the middle legs of the pots? Except Volume 2 goes direct to the output jack, and then to the 2nd leg of the volume pot? Am I getting this right or am I way off? Thanks so much, your site is awesome!
ReplyDeleteIf there is also a good resource for this, let me know...all the offboard wiring tutorials I've found address everything but this it seems.
DeleteThis should answer most questions. In this case (and many others) the output of the effect doesn't come from the layout but volume pot lug 2. https://tagboardeffects.blogspot.com/2012/02/offboard-wiring.html
DeleteThanks for the response. Does this mean I daisy-chain Volume pot lug 2 to lug 2 of frequency, resonance, and lfo? Also, what then are the off-board wires Resonance 1-3 and so on for then? Also, if lug 1 is ground, I still don't understand the point of Resonance 1.
DeleteNo, no daisy chaining. Just take Anders' instructions at face-value. "Resonance 1" would connect to that pot's lug 1 etc. Your volume lug 2 becomes your effect output which is connected to your 3PDT switch. The link I added shows the Skreddy method which is pretty standard. I use it most often.
DeleteFor the "switch" connections (this is another switch, not the foot switch) the DPDT lugs are numbered like this:
1 4
2 5
3 6
You jumper lugs 3 and 4 and that is your effect input. So that is connected to your foot switch input.
I get why I've been so confused, I never saw a 3PDT switch anywhere in there and thus didn't know it had one...shoot.
DeleteThis will probably make everything (including your link) make a lot more sense.
DeleteYou could use a DPDT switch for the bypass switch but you wouldn't have a status LED. I'd suggest getting some 3PDT switches.
DeleteWired everything up accordingly, and as tagboard effects required. All I'm left wondering is, what's the LED+ cable about? Did I miss something with the wiring of the 3pdt status LED or is this unrelated? Is it necessary?
ReplyDeleteIt's connected to the CLR resistor on the board - it's just there to connect to the positive leg of the indicator LED so you don't have to use a resistor offboard. If you have pre-wired LEDs or just don't want to use it, you can just leave it out, no harm.
DeleteMany thanks!
DeleteAnother verified build! thanks for all the help!
ReplyDelete