3D "AIR" EQ - "Night EQ" PCB's Complete!

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fazeka said:
Hey all,

I have a dead original Nightpro unit from the late 90s. I suspect it has corroded traces, some bad enough to cause a channel not to work. I think it's bad enough to where stopping the corrosion is too late... so thinking about having these PCBs cloned, wondering if anyone could help? I would like to have these cloned to use with the original pots and switches (and their positions, that line up with the front panel) of the original. Also, the footprint of the power supply and the interconnect between the two boards would mean it would be a simple drop in replacement into original cases. And I get to use the original switched mode power supply...

But I may be just dreaming at this point...  :eek:

If anyone can assist with this, please PM me. Thanks.

Otherwise, Peter, if you are reading this, do you happen to have an extra pair of PCBs lying around?  ???

Post pictures of your unit, and the bad traces.
It can and should be fixed.
No new need for new pcb's

Bad traces can be redone, corroded traces should be cleaned with Iso Alchool and them brushed and then thin them with solder.

After the fix, you should clean everything, all the tracves and then use some PCB varnish to seal the traces and prevent them from corroding in the future.


As your question about cloning, that has been done already, it's the reason why this thread exists.

If you don't want your unit, I have some 3D "AIR" EQ - "Night EQ"  pcb's , we can make a deal to exchange your unit for a cloned one.

Best regards
 
fazeka said:
2. I acquired this unit because it was original and because I suspected a simpler more straightforward fix at the component level. Moreover, if I wanted to build a clone, I would have by now and not bothered with this original.

Well you were asking for a clone. That's what's you u wrote
 
Just putting my eq together but the green psu is acting up.
I've confirmed all components.
I built 3 of these and all acting similar
23.67V
-14.74V
7.37V

.93V
-10V
9.71V

23.7V
-14.77V
7.31V

Thanks to anyone who has suggestions
 

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I noticed a low output from the bridge rectifier on the positive rail.
Although the datasheet is similar to the recommended BR64, I installed the BR310.  Should work?

I also noticed the schematic on the twin-x site differs from the overlay which is the actual circuit.
The circuit seems to have two additional 1N4007 highlighted in yellow.

Should these be excluded?
 

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But why do you want to use +48v on your PSU?
This EQ doesn't need it, unless you want to combine this EQ with some other preamp into a single case.

I would first try and take out all the components related to +48v, and then see what is going on with the rest of the supply.
Possible causes of malfunction could be wrong wiring on the AC input (maybe you've switched ground and one AC supply??)... then maybe wrong orientation of the bridge rectifier, some other diode or elecrolytic cap?
Inspect that.
In most cases it's something stupid.
Happens to all of us  ???

:)

Luka
 
Using one of the three power supplies for an access 312 preamp, therefore required the 48V

I stripped all components out of the 48V section, and it dropped the negative rail from -14.97V to  -11.41V and brought the positive rail from 7.53V to 11.41V.
Pulled every component until there was nothing left. Finally had +15V and -15V on the rectifier.

Every resistor was checked 10x as I spend the entire day at this, plus many hours last night.

The only thing that I question is the use of wima caps for the 100nF instead of electrolytics, (Which the overlay doesn't have a + or - marker, but the bom states electrolytics) the BR310 instead of the BR64 and the voltage regulators were KA317TU instead of LM317T.

I don't believe any of those things matter; as I've been over the data sheets.

I'm at a loss, and probably just going to use a JLM now.
 
Le Roux said:
Using one of the three power supplies for an access 312 preamp, therefore required the 48V

I stripped all components out of the 48V section, and it dropped the negative rail from -14.97V to  -11.41V and brought the positive rail from 7.53V to 11.41V.
Pulled every component until there was nothing left. Finally had +15V and -15V on the rectifier.

Every resistor was checked 10x as I spend the entire day at this, plus many hours last night.

The only thing that I question is the use of wima caps for the 100nF instead of electrolytics, (Which the overlay doesn't have a + or - marker, but the bom states electrolytics) the BR310 instead of the BR64 and the voltage regulators were KA317TU instead of LM317T.

I don't believe any of those things matter; as I've been over the data sheets.

I'm at a loss, and probably just going to use a JLM now.

Wait... Chill Out.. Let's take one step at a time

BR310 instead of the BR64

I don't know what it is the 310 or 64, you need a Bridge Rectifier rated 1 Amp or more, does your fit the Bill?
If so, move on

The only thing that I question is the use of wima caps for the 100nF instead of electrolytics,


That doesnt make a diference, move on


KA317TU instead of LM317T.


Same thing, move on

The circuit seems to have two additional 1N4007 highlighted in yellow.


Those are protection Diodes, leave them and move on





 
Troubleshooting of the PSU:

- What transformer are you using, whats the secondaries voltages?

- Did you properly connected the transformer secondaries to the PSU?

- Do you have the Bridge Rectifier properly installed?

- What AC voltage do you have at the BR input?

- What DC voltage do you have at the BR output?

- Measure and post the voltages you have at each regulator input and output

- take pictures of the setup, pcbs and transformer and connections

If you are feeding the 317 regulators input with +15V you wont be able to regulate the output to +15V,
you need at least 1.2V more at the input than at the ouput. In reality just to be safe I would have at least 17V minimum at the input if I wanted to regulate the output to 15V

 
Yup. You're right.  :) And I guess I overreacted earlier... it wasn't really bad at all!

There were only a few traces that needed a touch-up. Then as you say I cleaned the boards with iso alcohol and did a recap as a few caps were open and all is well again. Great sounding EQ! I can see why these are in demand!

Thanks,
Chris

Whoops said:
Post pictures of your unit, and the bad traces.
It can and should be fixed.
No new need for new pcb's

Bad traces can be redone, corroded traces should be cleaned with Iso Alchool and them brushed and then thin them with solder.

After the fix, you should clean everything, all the tracves and then use some PCB varnish to seal the traces and prevent them from corroding in the future.

As your question about cloning, that has been done already, it's the reason why this thread exists.

If you don't want your unit, I have some 3D "AIR" EQ - "Night EQ"  pcb's , we can make a deal to exchange your unit for a cloned one.

Best regards
 
dlmorley said:
Is this project still live? Are PCB's available?
Thx!

It is your first post, so you should read the forum rules first:

6. Use the search function (thoroughly) before posting.  It is quite possible your question may have already been answered by knowledgeable members that have been generous with their time.  A tremendous wealth of knowledge is actively updated and compiled in the "Meta" threads--take advantage of them.

 

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Hi guys, I'm wiring up the lorlin switch and I'm not sure how to do it. Already did a search but I didn't find anything.

B 2 3 4 5 6 is pretty obvious
A also but where do I connect the 2-6 on the pcb?

Kind regards,

Peter
 
choolder said:
A also but where do I connect the 2-6 on the pcb?
"a" and "2-6" are 5mm apart, located close between the 2500Hz and HI-SHELF level pots.
"2-6" is a piece of shorting wire, soldered to the pins 2,3,4,5 and 6 of the "a" section of the lorlin type switch with the other end of the wire connecting to this "2-6" spot on pcb.
 
So I have an ORIGINAL of this unit on the way ... the big 2u, blackface unit ...1/4dB stepped dual concentric switches , linear power supply, transformer balanced outputs.. . I am excited to scope it out.

I also have the original manual for the Eq3 (not 3d) if anyone wants to see it.

Specs from original manual :
input impedance - 20k Ohm
Output impedance - 50 Ohm
Headroom : +25dbm
max phase shift : 30 degrees (one control set max, all others set flat)
musical phase shift : 10 degrees  (controls adjusted for average musical compensation)
+/- 0.5db : 10Hz-125kHz
+/- 3dB : 7Hz & 330Khz



I do have a question ... has any one swapped the 5532/5543 opamps in these? Given the way this circuit works, (band split summing) what would be a good fit? Their socketed, so would seem an easy way to experiment with the tone

I'm thinking of modding the air-band on these with a switch to add the select frequencies (like the Eq3d/EQ4). I used to have those schematics from a prior build, but I seem to have lost them ... does anyone have the section for the air-band freq selector? I'm thinking just adding a 6-pole switch to the front of the stock unit would be easy.

I'll update with more info next week ... Those grayhill dual concentric switches cost a pretty penny!! So I'm excited for the 1/4db control this will offer


(also to the poster a few pages back ... the unit is correct with only -4dB cut, and +15dB boost ... that's the way it's built).
 
Check the wiring first, you don't know who might have messed around with the unit before. If it everything works properly and both channels sound the same maybe it's just pin2 and pin3 that are swapped.

I
 
Yup .. input was swapped. working perfectly now.  -- Attached is the filter board + knobs. (Grayhill series 71) pic --

They *really* didn't want people getting into this thing! .. I had to chip out  a bit of concrete or epoxy two screws had been filled with, and also had to slot a stripped bolt with the dremel to get it out.

But inside it's built like  tank!  Big whooping transformers on the outputs, sealed switches, thick traces, IC's had the labels scrapped off and aren't socketed. It's a very nice sound on program ... I'm going to hang onto it for awhile and compare it against my (original) Sontec 430b, and Bettermaker as far as the 'air' shelf goes .... all 3x are known to be excellent.
 

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