[BUILD] All things RackNeve

[Ilya]

Since there is sufficient amount of RackNeve kits floating around, I decided to open this official support thread. All build questions will be answered here.

Meanwhile, here're some useful links that will get the builder started:

Standalone units:

RackNeve 1073-type preamp and EQ building guide.

4-channel frame modules:

Our 4-channel frame system explained.

  1290 type mic preamp building guide.

  Passive 1073-type EQ building guide.

  1176-type compressor building guide.

  PYE-type compressor building guide.

  312-type mic preamp building guide.

Universal PSU building guide.

 

[WantsSweetRelease0091]

I bought the PCB boards off of RackNeve for the PYE Compressor, and I've noticed that there are some differences between the BOM and the shipped PCBs.  It looks like the BOM is for Revision 1.4 of the boards, and Revision 1.5 is what's being sold.  There are 2 resistor spots that are not mentioned on the BOM for revision 1.5 that I found.  What are the resistor values for Revision 1.5, locations Rm12 and Rm103.  Kinda stuck here.

 

[Ilya]

Welcome to the forum, WantsSweetRelease0091!

Rm12 is 200k, Rm103 is 47R.

Thanks for letting me know. I've updated the BOM with these missing resistors.

 

[WantsSweetRelease0091]

Awesome, thanks!  Are there other updates to the BOM across the revision?  I've already installed quite a few components and don't really want to continue without making sure values haven't changed for certain spots or anything.  If the whole BOM has been updated, could you upload a PDF for revision 1.5?  Or has the BOM on the site been completely updated?

 

[Ilya]

Awesome, thanks!  Are there other updates to the BOM across the revision?

The Rev 1.4 is an internal revision, it has never been released to the public. All BOMs for all projects are current. The way I work on projects makes significant changes in BOMs highly unlikely. The only exception is VR racking boards which have separate BOM for V3 and upward.
Looks like these components in PYE BOM were missed during creating of the page.

I'm not planning to make PDFs because this is just another place to correct in case there're some components substitution. And Mouser often stops carrying some components in favor of another. So keeping all those documents in sync will require a lot of time and effort. Currently all BOMs are online and will stay this way.

 

[mrclunk]

Planning on buying a couple of the Pye PCB's.
Whats the deal with the blocking oscillator transformer?
Will u be selling these or is there a standard part i can order for it?
thanks

 

[Ilya]

Planning on buying a couple of the Pye PCB's.
Whats the deal with the blocking oscillator transformer?
Will u be selling these or is there a standard part i can order for it?
thanks

Nothing complicated really. It's a small toroidal transformer with a couple of windings. Each winding is very short, so you can easily wind it yourself.

I'm not going to sell those, you'll have to wind your own. I provide all information regarding the core and winding structure in the guide.

 

[mrclunk]

Ok, great thanks Ilya.

 

[WantsSweetRelease0091]

Hey Ilya,

I'm still on the PYE build, and I'm running into some more problems:

1.  How are the boards mounted to the case?  Not just how are they mounted in terms of hardware needed, but also where in the case do I put the boards?

2.  The enclosures don't have any mounting holes.  Since I'm going to need to drill holes into the case, I'd like to know where EXACTLY to drill the holes.  The case is expensive and I don't want to freestyle the holes.  If it's possible, could you please upload a diagram or a picture of where to put the holes and the boards?

3.  Are there pictures of how to mount the boards onto each other?  I don't quite understand how to piece things together.

Thanks for all of your help.  I really appreciate it.

 

[Ilya]

I explain all metalwork in the "Enclosure preparation" step. There are drilling templates that aid in marking the holes location. These are A4 drawings outlining the exact location of 4 modules placeholders inside the case. Print out these PDFs (make sure you have NO scaling in your print dialog). Make sure that mouting holes on the paper align with the mounting holes on the module motherboard. If not - there're some issues with the printer scaling that you need to fix.
On the templates there's an outline of the enclosure lid. Cut out the template using these lines as a guide. What you'll end up is a piece of paper that represents the enclosure lid with modules mounting holes marked. Now you need to fix this template to the enclosure lid. I use a paper masking tape for that. Make sure to align the edges of the template and the actual lid. Also, there's a screw hole on the template near the edge - make sure it's aligned with the actual screw hole in the lid.
After fixing the template to the lid use a center punch to mark the holes. Now you can remove the template and drill the holes with 3mm drillbit. If you plan to install all modules I suggest that you drill all holes - this will make your life easier and you won't have to drill an enclosure with electronics in it or unmount everything to drill some new holes.

You can also check out the metalwork page in the RN73 guide. It uses different templates, but the procedure is the same:
https://www.rackneve.com/1073Guide_MET

Now, regarding modules placement. I place all signal processing modules to the left, and the PSU board goes to the right (this is if you look at the enclosure from the front).

I'm using threaded rivets instead of stand-offs, but they require a special tool to install. If you have that tool you'll need to enlarge the holes to 5mm so the rivets will fit. If you're going to use stand-offs, no more drilling is required. Just screw four 5mm stand-offs to the mounting holes and you're done. Since the stand-offs are so short, you'll need to use very short screws so there's some thread left for board mounting. Another option is to use a long screw so that it goes all the way through the stand-off. This way you can secure the board to this same screw with a nut. Yet another option is to use male/female stand-offs.

As for module stacking, this is explained in the "Assembling the module" step, the very first photo. Take the motherboard, screw it to the stand-offs. You'll need 2 screws and 2 15mm male/female stand-offs. The stand-offs go under the marked screws on the photo - you fix the motherboard with the male part of the stand-off, on top of it you have a hole for fixing a meter board.

Let me know if anything is not clear. I'll see if I can make some photos of the module.

 

[WantsSweetRelease0091]

For the grounding, do you use the star ground or the earth ground, or both, to connect to the IEC?  Also, what is the best way to connect the Power Transformer to the IEC, power switch, and to the PCB boards?

How do I use the pair of 20V connectors on the main board, and also do I connect anything to the 16V power spot on the main board? 

Also, how should I link the meter baords together (doing a stereo build.)  Do i just connect the two headers? 

Just trying to figure out the wiring.  Thanks again for all your help so far!

 

[Ilya]

I connect grounds at the board (chassis GND and audio GND, I do this on all boards) and connect this juction to the IEC ground. I do this IEC connection either from every board or just from one board (I listen to the amount of output noise and decide what's better). As for the power transformer, I suggest that you look at the RN73 PSU wiring, the very first couple of steps:
https://www.rackneve.com/1073Guide_PSU
Now, you can't connect the power transformer directly to the module. You need to take an otput of the PSU module and connect it to any of the 20VDC connectors (they are in parallel). Make sure the polarity is correct. You can take power to the second module from the 20VDC|| header.

16V header is an output from power regulator at the module board. You can use it to check if it works correctly.

For linking you connect "LINK" on the board to the "LINK" on the front panel PCB where the link switch is. And connect "LINK->" headers at the link switch PCBs between the modules. The first pin goes to the first pin, second to the second.

Initially there was a question about the 555 oscillator, This board has 3 pads (hexagonal) that align with the same pads on the module PCB. You stuff that board and solder it to these pads. You can use component leads as connecting wires. Make sure there's some room between the boards so they don't short. And you don't need to populate the discrete oscillator section of course.

 

[WantsSweetRelease0091]

I'm looking at this picture to try and figure out exactly what to do, and I'm still a little confused.  What are the wires that are going underneath the board? 

Also, we are wiring in 110V.  How would you wire to the power switch in parallel?  Is that what is done in the posted picture? 

If we're doing a 2 unit module, do we use just one of the 20V outputs to power the modules?  Is there a more detailed schematic for the 4-channel power module?

EDIT:  OK, so the power is connected, and power seems to be passing through fine.  The board that the power is directly plugged into seems to be working fine, but the board that is connected via the 20V connector has one input light on and four gain reduction lights on.  Plus, touching one of the resistors on the Meter Driver board causes more gain.  I haven't tried passing audio through yet. 

Are there any considerations going forward?  I'm new to making outboard gear, so any help on diagnosing the issues would be great. 

 

[WantsSweetRelease0091]

Also, I just got to thinking that some of the wires may be causing the problem, like a connection isn't working somewhere.  Could bad molex cables be the problem?  I'm new to troubleshooting things like this and could use all the help I could get.  So far all your help has been great and has gotten me past quite a few issues!

 

[Ilya]

I'm looking at this picture to try and figure out exactly what to do, and I'm still a little confused.  What are the wires that are going underneath the board? 

Also, we are wiring in 110V.  How would you wire to the power switch in parallel?  Is that what is done in the posted picture? 

Please refer to the attached picture for mains wiring directions. On the photo you mention the unit is wired for 220V, but this is irrelevant. Wiring going back and forth is actually wires from IEC inlet to the power on switch on the front panel and back to the transformer.

If we're doing a 2 unit module, do we use just one of the 20V outputs to power the modules?  Is there a more detailed schematic for the 4-channel power module?

You can find the PSU board schematic here:
https://www.rackneve.com/uPSU_Guide_RefDocs

Please check that you have V1.x version of the PSU board. If you stuffed the "V1" section, you need to connect the output from "V1_DC" header to the modues 20VDC connector (check the polarity!). You also need to connect the PYE modules ground to chassis. For powering the second module connect it to the 20VDC|| as I outlined earlier.

EDIT:  OK, so the power is connected, and power seems to be passing through fine.  The board that the power is directly plugged into seems to be working fine, but the board that is connected via the 20V connector has one input light on and four gain reduction lights on.  Plus, touching one of the resistors on the Meter Driver board causes more gain.  I haven't tried passing audio through yet. 

Are there any considerations going forward?  I'm new to making outboard gear, so any help on diagnosing the issues would be great.

Try listening to the output of the modules and see if there's any difference. If there is, the meter board is probably fine and it's the module that's faulty. If not, than you should check your meter board for errors. Molex connectors are quite reliable and I've never had any issues with them. If you doubt your connection you can check the continuity with the DMM. Make sure the unit is powered off completely! You should measure close to 0 ohms resistance.

If you find that one of the modules works fine and another is not working properly, you have a reference to compare to. Measure voltages at transistor and compare them between the modules. Let me know if there are significant differences.

 

[WantsSweetRelease0091]

Could the meter problem be an IC chip issue?  One of the IC chips is broken on one of the meter boards, and to test if it was an IC chip issues I was swapping the IC chips from the working board into the other, and that's when one of the IC chips failed.  So now, unfortunately, I don't have a reference module.  I'm asking because I'm thinking of ordering all new ICs, but if that's not a likely solution I'd rather just get the one that I need for sure.  It was the Um52 IC chip that failed.  It smells like it burned out.

 

[Ilya]

Um52 acts as a buffer and precision rectifier. If it fails than it will affect the signal level indication. Did you socket ICs? if no I recommend getting some extra ICs because you can easily damage them during desoldering. If yes, change Um52 and see if it solves your problem.

Did you test the audio path?

 

[WantsSweetRelease0091]

I haven't tested the audio path yet.  Is that possible without the IC chip in?

 

[Ilya]

I haven't tested the audio path yet.  Is that possible without the IC chip in?

Absolutely. You can test the module without the meter board just fine. You won't have any indication, but compressor should work fine.

 

[Ilya]

Announcing plans for the following year:

https://www.rackneve.com/RackNeve_2018_year_plan