Orange squeezer vltgs (GGG vs. Torchy's vero layout)

Started by analog kid, October 13, 2005, 04:38:31 PM

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analog kid

 A couple of questions here. First I just built the stripboard layout for the O.S  that  by torchy.  After firing it up and taking vltgs I notice some things that make me curious about this layout vs. others.... I used the search function to see if any threads referred to differences in orientation of  IC , etc.. between the PCB and strip layouts and found nothing.  My point?
-The voltages at the GGG project state IC pins 3 and 4 should be at 0 vlt.
Where the strip layout has  pins 4 and 5 tied together at ground so  OF COURSE this is where I get my 0vlts. NOT at 3 and 4. 
So I am wondering if the IC  is somehow oriented differently in Torcy's layout I have the schematic and am going to try and look for differences but thought someone would  KNOW already if this is the case
Another reason I worry of this is.. (but it may be a mistake somewhere as well) is that GGG shows Pin 8 at batt vlts , of course, and Pins 6 and 7  around 4.5vlt With Pins 1 and 2 at above 8 volts 
BUT...... on "MY" strip O.S. I am getting the Pin 8 batt.vlg  although Pins 1/2 and 6/7 are almost exactly reverse of the GGG vltgs.!( I have 4.4v on 1/2 and 8.3v on 6/7) 
   obviously I should state that the crkt is functioning volume and trim works normal but I can't tell if the squeezing is present as it should be? I DID however use J201's. But if the voltages are this wrong it would'nt be right.
Main question: Are the voltages on the GGG site Correct?? (pins 3 and 4 Zero Volts.) that wouldn't seem to be possible since pin 3 IS connected based on the schems I've seen. And if correct would they differ at all from the stripboard vers.?
See the man with the stage fright, just standing up there to give it all his might..

spudulike

GGG uses one half of the dual op-amp, the strip layout uses the other half. Probably just for a simpler layout on stripboard ?

analog kid

Ok great! You do know that for sure then? I only ask because the Orientation is the same as far as 1/8 goes. Meaning Pin 8 still holds +9v, so I guess this would be the same regardless of which half of the opamp is employed in use in the crkt.  (?)
SO , with my voltages , STRIPBOARD Layout, being as following... would you say that the circuit is functioning as properly as it should?
Battery 8.5v
IC
Pin 1  4.58
Pin 2  4.58
Pin 3  4.48
Pin 4  0
Pin 5  0
Pin 6  7.86
Pin 7  7.86
Pin 8  8.45v
  if it matters to know there is no continuity between 1/2/3 they are wired correct
Q1 D
    S
    G
Q2 D   (0-.880v)
     S  (0-1.1v)
     G 0
These are depending on the trimpot setting. When set at highest compression the drop between D( .470v)and S (.448v) is very small.  When pot is up CW the drop between D and S becomes a little larger. ie; 1.1v / .880v   
This tranny bothers me. and as i said I used J201s as all my 5457's are in use
See the man with the stage fright, just standing up there to give it all his might..

analog kid

Can anyone relate to these vltgs in the context of the stripboard layout?? :icon_neutral:
See the man with the stage fright, just standing up there to give it all his might..

MartyMart

Pin 8 is always 9v on a dual o/a
Pin 4 is always ground on a dual o/a
So, 1-2-3  and 5-6-7 are interchangeable, as they are equal "halfs" :D
( inverting input, non inverting input and output )

If your circuit seems to work fine then no worries, I have a build from
that layout and it works a treat, its even inside an old "OS" original case !!
Sorry I can't get to the voltages right now  !
J201 should work OK instead of the 5457, does it go from "off" to "compressing"
to "overloading" as you slowly raise the trimmer ?
The only "bummer" is that I have about 3mm of movement which adjusts the
amount of compression - that's not much !!

Marty.
"Success is the ability to go from one failure to another with no loss of enthusiasm"
My Website www.martinlister.com

cab42

Quote from: analog kid on October 14, 2005, 02:03:24 AM
Can anyone relate to these vltgs in the context of the stripboard layout?? :icon_neutral:

There are some voltages in the build instructions on GGG. Just remember to into account that it's the other half of the opamp that's used in the vero layout (see marty's post).

I build the vero version a while ago. It behaves as expected, but I simply can't hear any difference between effect and bypassed sound.

But now that I have your readings I will try to dig mine out and compare.

Regards
Carsten
  • SUPPORTER
"Rick, your work is almost disgusting, it's so beautiful.  Meaning: it's so darned pretty that when I look at my own stuff, it makes me want to puke my guts out."
Ripthorn

analog kid

SORRY I took so long to respond to the help you guys offered, Got hung up on other builds and neglected to check the post. ! I got some of the new Plastics Paint (orange) to paint the gnx little black plst box I am sticking this in. Not even a stomp , just a 3PDT Toggle.
Anyway..
"does it go from OFF to COMPRESSION to Overload as you turn the trimmer?"
  Well yes and no. It goes from EXTREMELY LOW volume at fully ccw but still audible with amp/effect volume up a bit, then kicks into normal'ish volume level and what little pumping/breathing that I can hear does seem to be at it's max here, then into too hot of a signal after that. So I thought this was working ok except for the off trimpot position still showing some signal and not dead off (?)

cab42 said  "I build the vero version a while ago. It behaves as expected, but I simply can't hear any difference between effect and bypassed sound."
This is also the problem I have with my build I have to judge by voltages being correct with examples to know mine is NORMAL, because I've never heard/played a proper working real O.S. before. Only on records. And being that I hear very little difference between on and bypass aside from a Volume control of course and only the SLIGHTEST amount of compressed thump  as I pluck strings  mostly on the low E and A. So I don't know if this amouont of comp is normal.  I
ALSO  I can't tell if the tranny voltages look within reason with examples? are they ok.  And as far as the IC  from the dual to single versions , what you are saying is whatever vltgs got on pins 1 2 3  with a dual amp , should be the same voltages but on 5 6 7 when a single  op amp is used / and a likewise 'flip' with  5 6 7  being 1 2 3 on the single.  Correct? :icon_confused:


See the man with the stage fright, just standing up there to give it all his might..

cab42

Quote from: analog kid on October 22, 2005, 03:53:29 PM

ALSO  I can't tell if the tranny voltages look within reason with examples? are they ok.  And as far as the IC  from the dual to single versions , what you are saying is whatever vltgs got on pins 1 2 3  with a dual amp , should be the same voltages but on 5 6 7 when a single  op amp is used / and a likewise 'flip' with  5 6 7  being 1 2 3 on the single.  Correct? :icon_confused:

Answering from memory (I'm on work and don't have time to check) it's not a question of single/dual opamp. Both in the verolayout (from Torchy) and in the GGG version a 4558 is used, which is a dual opamp, but only half of it is used in the O.S. And the GGG layout uses the other half compared to the vero I used.

I have seen a dual O.S layout, that uses both half's of a dual opamp (also a 4558) to get two O.S. in series.

Wow, think that I should answer a question on Opamp pinout. Now I just hope it's correct  :icon_wink:

I'll try to dig out my O.S. and check it. I really want to finish it. I just really don't know what to expect. I have never tried a compressor before!

Regards

Carsten
  • SUPPORTER
"Rick, your work is almost disgusting, it's so beautiful.  Meaning: it's so darned pretty that when I look at my own stuff, it makes me want to puke my guts out."
Ripthorn