Introducing the "One Chip Chorus"!

[rhcp_schipper]

Install a trimpot. Season to taste.

You mean a voltage divider trimpot, or in place of that 330k resistor?

[oldschoolanalog]

Trimpot set up as a variable resistor in place of the 330k resistor.

[Jumbosize]

I have a quick newbie question for reading the circuit: Does the "Vr" get connected to the +9V?

[pinkjimiphoton]

yes.

[artifus]

yes.

sorry jimi, not familiar with this circuit, but doesn't vr normally refer to reference voltage, usually 4.5v in 9v pedals?

*apologies if i'm wrong - just don't wanna lead a noob astray*

http://www.datasheetcatalog.org/datasheet/PrincetonTechnologyCorporation/mXyzsyzt.pdf

[pinkjimiphoton]

i thought that was vb that was the half voltage arti...

i may be wrong, and probably am, knowing me.

looking at the vero on page one of this thread, r8 and r9 connect via a jumper to 9v b+

i thought i may have been mistaken, so i went back to look to be sure...

if that's a mistake on the vero, it may explain why i can't get my build to work....which is weird, cuz i DID get it to work like a 1 slap delay.

please check page one of the thread, i really have a hard time trusting my eyes lately.


EDIT: i just checked the vero and the schematic, and it's indeed referencing the full 9v as shown on the vero, at least...

[artifus]

cool. as i said, i'm not familiar with the circuit - i just saw the question 'should i connect vr to 9v' and responded. i'll try and keep my noob mouth shut in future. apologies for any confusion, folks.

[pinkjimiphoton]

no, bro, please don't ... i believe you are actually right, the confusion may be in the nomenclature used...

pretty sure vr is voltage reference, and vb is bias voltage...

hopefully one of the rockstar guys who know what's what will be able to set us ALL straight.

[Jumbosize]

Well I actually found a successful solution that is different from what both of you two were saying haha. I read in one of the earlier posts that you are just supposed to connect the two Vr points together, not connect them to the 9v or anywhere else. I did this and it worked like a charm. I guess I'm a little confused as many of the layouts made by others depict this done otherwise but hey, it works. I'm not gonna question it.

[Earthscum]

I haven't played with this in awhile and dug it out (and my unpopulated PCB). Jeezzuss!!! Between ONE build of this and ONE build of the Harmonic Energizer, I used a total of 15x 10uF electros. 

[Vardok]

Hi everyone!!!

Anybody try the Mad bean layout to see if it works with the extra knob?

Joel

[anchovie]

...and after over a year since designing it, I finally built my own vero layout! Changed R3 to 470k.

Many thanks to all who verified it!

[Ark Angel HFB]

Ok orders the part I need with enough chips to try a few.

Will keep you guys posted. ^_^

[Ark Angel HFB]

Ok so I  made the circuit... Really  messed up the board by making the cuts as if I was facing the strips... basically had to flip the circuit around not a big deal...

what is a big deal is, I wired my power wrong and got the whole tip negative thing wrong... just got confused on which lug in the dc jack was tip and what not....

Anyway... I plunged it in like this and got no sound. The I realized my mistake and flipped things around, and it now passes sound... but there are some problems...

Getting the pulsing sound that repeats at a steady rate.... Think this means the LFO is working.... problem is I'm not really hearing any chorus... it is almost like I have my normal sound with an added buzz plus the LFO pulsing thing... I've tried another chip and get the same results so now I just need to know...

Did I screw anything up with the Frist power inversion and if not what is the problem.

[anchovie]

First thing to do would be to measure voltages on all the pins of the chip and regulator.

[Ark Angel HFB]

Regulator
p1 16+
p2 0
p3 4.8

Chip (I don't know the numbering so I'm doing it as if you count down one side of the chip then the other... starting from the side with the dot on it as pin 1.)
1 4.87
2 2.22 to 2.68
3 0
4 0.25
5 1.3
6 2.26 (jumps around a bit)
7 2.26 (jumps around a bit)
8 2.26 (jumps around a bit)

9 2.30 (jumps around a bit)
10 3
11 .19 to 4.80
12 2.38 (jumps around a bit)
13 2.80 (jumps around a bit) (Modulated single present.)
14 2.40 (jumps around a bit)
15 2.4 to 2.6
16 2 to 3

Let me start by saying that since the circuit pass signal without being plunged in... that means that the dry signal line is working....

I probed all pins and from 13 I'm getting a modulated signal. However the sound is rather harsh and there is some background hiss and crackle. Turning VR1 does effect the signal I'm getting from here but over all it seems to have no bass and sounds thin and bad...

However I hear no effect when it is plugged in and I take my sound from (B20).

I think what I'm hearing from pin 13 is the signal 100% wet, and the hiss/crackle is the 2.8vDC that is on that pin.

So it would seem the regulator and the chip are working, The dry signal line is working, but that something is wrong with the wet signal line... so starting from (H10-H20)... i need to check every component that carries the wet signal to the output jack and see what the problem is....

or is there something off in my voltage reading I provided???

[Perrow]

Chip (I don't know the numbering so I'm doing it as if you count down one side of the chip then the other... starting from the side with the dot on it as pin 1.)

[Ark Angel HFB]

Chip Reading now that I know the pin out... Thank you btw.
1: 4.87+
2: 2.22+ to 2.68+
3: 0
4: 0.25+
5: 1.3+
6: 2.26+ (jumps around a bit)
7: 2.26+ (jumps around a bit)
8: 2.26+ (jumps around a bit)

16: 2.30+ (jumps around a bit)
15: 3+
14: 0.19+ to 4.80+
13: 2.38+ (jumps around a bit)
12: 2.80+ (jumps around a bit) (Modulated single present.)
11: 2.40+ (jumps around a bit)
10: 2.4+ to 2.6+
9: 2+ to 3+

[Ark Angel HFB]

Ok I got mine working correctly...

Guess it helps when you don't forget to put R13 on the board... >_>

Honestly I love the sound but it seems to freeze up if left on and I don't play for a while... will have to see if I can fix this or it still isn't useful...

Side note... the sound is rather nice and very organic sounding... it doesn't sound digital or bad in anyway... a real winning pedal... if I can fix the freeze up problem...

[Ark Angel HFB]

How would I go about brightening this circuit up without making it too thin... or the volume be below unity?

It sounds really nice but it is a a bit too dark...

I Ideas?

I was thinking maybe another stage with a simple boost circuit? or what?