1176 Plosives: looking for Rev A schematic or high res internal shots

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Thanks
I have changed the 3 resistors
and the unit it's more controllable...
In nuke mode must be more light with input and attach pot...

I have used attack pot with off switch
from hairball connection but I don't understand pad 22 where is connected,
is connected to the ground?
Ciao :)
 
ilfungo said:
Thanks
I have changed the 3 resistors
and the unit it's more controllable...
In nuke mode must be more light with input and attach pot...

I have used attack pot with off switch
from hairball connection but I don't understand pad 22 where is connected,
is connected to the ground?
Ciao :)

Look at Here is there some conversation about the wiring...
Hope it helps...
Cheers,

Eddie :)
 
Hi all,
I'm in the same boat as Stagefright13 (I already finished my pair of blue strips and love 'em). I have no interest in the slam mode, i am intrigued by the r46 mod. i would prefer if the threshold were higher (particularly for 1:4), but would this resister swap mean that i would have to completely re-calibrate? I had some difficulties calibrating and i would prefer not to go down that road again for a while.
thanks in advance for any insight.
 
Well I have 3 Mono Rev D's and a stereo one, And 1 rev A. And don't use nuke on any of them LOL. You can really slam a track with the rev A or D. They are both so fast already. But both sound different. So glad I have both. But if ya want to use Nuke the best way is with parallel compression. Otherwise it is just an effect like a guitar pedal kinda.

And I was in Brooklyn last week and they had 2 1176's but no rev A's so could not try the nuke on one.

So glad people are working on this tho. I will consider messing with mine when it get's cold out and I have time. :)

But realistically it works fine just as it is. Actually more than fine. The albums are in stores LOL!

I'm sticking with Mako's original setup using the JBL Pro schematic. And probably less noise due to Mako's ground plane setup on his board.

John
 
ethervalve said:
Hi all,
I'm in the same boat as Stagefright13 (I already finished my pair of blue strips and love 'em). I have no interest in the slam mode, i am intrigued by the r46 mod. i would prefer if the threshold were higher (particularly for 1:4), but would this resister swap mean that i would have to completely re-calibrate? I had some difficulties calibrating and i would prefer not to go down that road again for a while.
thanks in advance for any insight.

This doesn't require recalibrating, all it does is lower the gain of the sidechain amp.
 
Thanks for the great investigative work Rob!
I performed the mod and it works great. I no longer have to trim down signals for a more manageable threshold. I'd recommend the 22k resistor for r46 for anyone out there building a blue stripe.
 
Ok guys, after comparing the various schematics (original 1176, rev A and Mako's rev A) I came across a bunch of values that should be the ones used on the real Blue Stripe. Of course those have not been checked with a real unit, so, please if you own an original rev A Blue Stripe check the values and report back !!!

I did this as an experiment, you don't need to change anything if you followed Mako's BOM, in fact his revision sounds really good as it is !
And well, Mako, thank you very much for the rev A !!!! A great board, an easy build, just lovely !

I've got the values comparing the Rev A schematic to the one used by Mako (Original 1176) which are the ones between parenthesis.

R6 = 2.2M (560k)
R7 = 2.2M (560k)
C6 = REMOVE (33pF across R16)
C6a = ADD 68pF across R7)
R11 = 9.1k suggested by Ed Anderson (10k)
R12 = 2.2k (1k)
R16 = 100k (47k)
R17 = 4.7k (8.2k)
C9 = 6.8uF (47uF)
R30 = 150k (120k)
C11 = 10pF (47pF)
Rx14 = REMOVE (820k)
Cx6 = JUMPER (6.8uF)
R76 = 10k (8.2k)
R54 = 1.2k (470r)
C27 = 0.012uF (0.022uF)

Ratio Board
=======

R22 = 47k (56k)
R19 = 68k (130k) NOTE: If you're using the great Hairball PCBs R19 is marked as R8 on the documentation
R78 = 47k (NOT PRESENT) NOTE: R78 is marked as R10 on Hairball PCBs
R64 = 2.2k (1.2k)

LINE AMP MOD
=========
This mod adds a resistor (3.9k) in series with a capacitor (1000pF) and it should be connected from the (-) of C9 to the junction of WHTRED - R32. Take a look at the picture.

1176%20Rev%20A%20Line%20Amp%20mod.jpg






 
Interesting...

I've been doing some research here as well.

Neeno said:
I've got the values comparing the Rev A schematic to the one used by Mako (Original 1176) which are the ones between parenthesis.

Some additional notes that I found.

There's two versions of the limiter using the 2 FET pre-amp.

Serial #101-125, original version, no revisions labeled on the schematic and
Serial # 125-216 which is labeled REV A on the schematic and appears to be
the version which you are pulling your changes from.

Mako implemented the pre-amp as detailed in the unlabeled, original schematic and
I'm assuming that the guys at Universal found this pre-amp to be slightly unruly and
made the changes in the REV A version of the limiter.

The Gain Control Amplifier is modeled after the REV D version of the limiter and
I have found detailed some changes there as well as some changes to the ATTACK
pot values.

Perhaps we should pool the info at this point to get to a true REV A version.

Mark
 
Great work Mark !
Please post the XLS file !
If you don't have a hosting service, send it to me by email and I'll publish it.
 
Hi, I just remembered that I had some original schematics laying around here
from the time I got my 2 used Bluestripes in 1982. BTW I STILL HAVE THEM .
javascript:void(0);
Here some informations about the pushbotton resistor values.

Effective serial No.125 subsequent  Date: 2/20/67 -R 10743

R21=56k ,R20=56K , R19=68K ,R78=47K , R61=470 ,R62=470 , R63=1.5K R64 =2.2K
R58=120 ,R22=47K

Effective Serial No.217 subsequent  Date: 6/20/1967 -R 10743 (present circuit Serial 293)

R21=56K, R20=56k , R19=68K, R78=56K , R61=470, R62=560, R63=1.5K R64=1.5K
R58=150 , R22=47K

Hope this helps:.!! I´ll make some highres pictures next days and post them here.

cheers

 
la-2a said:
Here some informations about the pushbotton resistor values.

Hope this helps:.!! I´ll make some highres pictures next days and post them here.

cheers

Awesome,

Are these ratio values from your copy of the schematic, or your actual units?

If you could also include some pics of the mainboard to verify against that would be a big help.

Mark
 
Great job La-2a...
And it's also great that you still have the original schematics, and well, of course the real units.
So you own an original 1176 and a rev A.

You're the one that can really help us getting a real rev A clone.
Now, it would be just great to have some high resolution pictures and if possible also a good scan of the schematics, since the ones we all own are almost unreadable at some spots.

Thank you for your help in advance.
I think we're all looking forward to hearing from you.

Cheers
 
Neeno said:
...
Now, it would be just great to have some high resolution pictures...

Page one of this very thread has some pretty clear photos of the internals of my original bluestripe, someone could check these resistor values against the various schematics...   ;)  :

EDIT:  Here is what I think the resistor values are:

Top left  rear  row: 1k, 560k, 1M, 22k, 6k8
2nd left rear row: 27k,  2.2M,  68k,  82Ω
3rd left center row: 3.9M, 2.2M, 270Ω, 1k8 , 910


Front left center clusters:
row 1: 3k9, 1k5, 680Ω
row 2: 10k (vertical) , 1k5,  1k (R44) , 4k7,
row 3,4:   1k5, 8k2,  2M7 (R74)

RIght top row: 82k, 1M2, 8k2, 560Ω
Right center row: 2M7, 10k, 150k
Bottom right row:  2M7, 1k5, 27k, 18Ω
index.php

 
Hi zmix !
Thank you for the pictures, I tried to track the pcb from the circuit, but it is pretty difficult.
In fact the pcb traces aren't really visibile, and the perspective doesn't help really.

If only I could have a chance to have a bluestripe for a day or two I'll do it of course.

In any case thank you very much for posting them, since we could easily identify almost all the caps and some of the resistors.
 
zmix said:
Neeno said:
...
Now, it would be just great to have some high resolution pictures...

Page one of this very thread has some pretty clear photos of the internals of my original bluestripe, someone could check these resistor values against the various schematics...   ;)  

Thanks for those!

I did check your photo's against the schemo. It turns out that yours is a REV B which doesn't have the dual FET pre-amp.

The info, we're looking for pertains to the earlier versions with serials under #216. A truly rare beast, but it looks like we might be getting closer.  8)

Mark
 
Biasrocks said:
zmix said:
Neeno said:
...
Now, it would be just great to have some high resolution pictures...

Page one of this very thread has some pretty clear photos of the internals of my original bluestripe, someone could check these resistor values against the various schematics...   ;)  

Thanks for those!

I did check your photo's against the schemo. It turns out that yours is a REV B which doesn't have the dual FET pre-amp.

The info, we're looking for pertains to the earlier versions with serials under #216. A truly rare beast, but it looks like we might be getting closer.  8)

Mark

I am aware that mine is a rev B, but Are you sure that the Rev B didn't have the dual FET? My schemo shows it, and  q4 is socketed, as are the other FETs....
 
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