Not completed Harrison 32C EQ PCB Designs

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Hi, I found months ago somewhere in the web schematics, non working Gerbers and a Layout of a 32C EQ of a Harrison Console. Does anyone know who designed them? I cannot find any informations? Does anyone know how to get the Gerbers working? The Layout and schematics look promising. Would be great if the Gerbers would work. But I have no experience in PCB designing...
Regards
>> HerbertR: Yer gonna need to re-output yer GERBER and N/C Drill files that are within your Post #1 ZIP file as they are fairly well HOSED!!! Here's just a very brief synopsis:

1) The -- SCALE -- between your GERBER files and your N/C Drill file is -- WAY OFF -- to be any good!!! As you can easily see in this screenshot that I got, your GERBER files are all scrunched down in the lower-left corner here. But, do you see those WHITE DOTS scattered around the rest of this screenshot??? >> THOSE << are your N/C Drill hits!!! More specifically, your GERBER files are set at -- 2.4 -- while your N/C Drill file is set at -- 2.7 -- so they don't match. Go back into your EAGLE PCB program and set both your GERBER and N/C Drill output file generation to be
-- 2.3 -- and you will be "GOOD TO GO"!!! Then, simply output all new GERBER and N/C Drill data files and ZIP them up for posting here.

And.....just in case you and/or any other members of this forum don't have any idea what these "numbers" (i.e., 2.3, 2.4, 2.7) mean, here's a quick explanation: the number to the LEFT of the "decimal point" refers to -- UP TO HOW LARGE -- a PCB or PCB-panel may be. In this case, the "2" means that a PCB can be -- UP TO -- 99-inches BY 99-inches in size. The number to the RIGHT of the "decimal point" refers to -- HOW FAR DOWN TO -- the resolution of the GERBER image will be. Again, in this case, the resolution of the GERBER files will go down to -- 0.001-inch (i.e., 1-mil) -- of resolution. SO!!!.....while you can certainly use other sets of numbers (i.e., 2.4 = 99-large X 0.0001-small [1/10th of 1/1,000ths!!!]).....there really is no need to use anything else other than 2.3 unless you're designing an aerospace PCB that is going into an orbital satellite!!!


1721503682660.png

2) As others have already pointed out, while your GERBER files contain the BOTTOM PASTEMASK, TOP & BOTTOM SOLDERMASK, TOP SILKSCREEN and BOARD-OUTLINE files, -- THERE ARE NO TOP & BOTTOM ROUTING LAYERS!!!

I will offer to you once again.....if you would like to send me your EAGLE PCB files, I will import them into my CADENCE/OrCAD PCB program and look things over for you. From there, I could go through your PCB output configuration settings and make sure that your GERBER and N/C Drill output files are setup correctly. And, if you wish, it would take me a couple of clicks to create the output files for you. From there, I can import them into the program I provided a link to earlier and check them out from that perspective as well. Or.....you can also do nothing and tell me to F*** OFF!!! Your call!!!

I've got an errand to run before the store closes, so I gotta go now!!!

/
 
Must complete the upper board... No spare time this period so i'm going very slow... Just assembled It to verify the mechanical part...
 

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Must complete the upper board... No spare time this period so i'm going very slow... Just assembled It to verify the mechanical part...
[Must complete the upper board] -- 1) It appears as though -- neither -- of the PCBs that are shown here to be mounted to the "Mounting Cube" are actually/truly -- parallel -- with the "Mounting Cube" and, 2) Is there a reason with why you aren't using a normal "Pan-Head" machine-screw to hold the PCBs to the "Mounting Cube"? "Flat-Head" machine-screws are used for countersunk holes in sheet-metal. 3) I had come across a really cool -- 222MB CAD ZIP-file -- that contains the most fantastic 3D CAD-models, even in color, of every type, size and shape of capacitor, diode, IC-chip, PCB-mount heatsink, resistor, transistor, etc. that I normally would have shared with you, but.....well.....you know!!!

1726455693241.png

/
 
everything is on axis! maybe the picture doesn't work because of the shadows... the board is inclined so it doesn't seem parallel... I used the screws I had, yesterday was Sunday! where to buy screws in the late afternoon? 3D models only serve me to understand the real dimensions, their purpose is only illustrative for me... what matters is the final result of which I am satisfied...
Hope to turn It on soon...
Anyway if you want to share your folder why not... It could shorten the timing for searching on line... And could also be useful for other people

Edit- the fixing screws between the cube and the panel were not well tightened... just screwed by hand so it seems off-axis
 
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Attached how I redrawn it...
input buffer -6dB to give headroom at filter section, after that section it is compensated to get nominal level at classB amp followed by crosscoupled balanced out
hope it's well done, if you find something wrong let me know so i can update it
as i turn it on and everything is as aspected according to simulation, i'll upload gerbers and front panel

best
 

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Attached how I redrawn it...
[Attached how I redrawn it] -- You can display and show your schematics as being -- larger -- if you use the "landscape" mode of your "paper" orientation instead of using the "portrait" mode. In addition, if you have a -- Margins -- setting, you can also set it to 0.50" (12.7mm) instead of the usual 1.00" (25.4mm).

By using both of these settings when creating a schematic PDF file, your schematic drawing will be much larger on the same sheet of "paper" and therefore.....much easier to read.

Just sayin'.....

/
 
Minimum HF range... And its shelving ....
The mids are fine too...
Very happy
I must update the PCB and schematic files cause i reverse wired the freq. Selection pots, and make a listening test as i can build a real psu and rack it to lunch-box so i can go to the studio to get a better check

Best

EDIT- used Bertom analyzer into Mixbus 32c daw to verify those slopes, in shelving mode i get more gain.... and it's what i setted into simulation to get a bit over 15dB at max..... instead the daw eq, if you set 6dB cut or boost, switching to shelving it is 7.3dB....
 

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a quick update....
had time to take the proto to the studio, it fits perfectly into the original API lunch-box, so mechanical is fine.
audio path is clean, and when engaged there's no signal difference when the eq is flat. Had some fun with vocals and drum....
I have to fix the gain when switched to Hi-shelv, which if you go over a certain amount I get oscillations and I hadn't noticed it in the simulation.
in any case the original schemo does not include the Hi-shelv...It's my variation
in the schematic i posted R57 in the upper board should be adjusted to get the right amount of gain when in shelv mode.

thanks for your attention

best
 

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