Small valve mixing console

[ruffrecords]

Well, the chassis sits at ground (safety ground connected in the power supply/0V/signal ground) in my case, that's why I use these terms interchangeably.

Which is the root cause of the well documented "pin 1" problem. They serve different purposes and the way and where they are connected together is very important. This is not reflected in your schematic.

Cheers

Ian

 

[MidnightArrakis]

Which is the root cause of the well documented "pin 1" problem. They serve different purposes and the way and where they are connected together is very important. This is not reflected in your schematic.

[This is not reflected in your schematic] -- It may be helpful to the OP if you provided either a hand-sketch or a KiCAD-sketch of how things are supposed to be so he can more easily "see" and understand the concept you are attempting to convey. That way, he can then update his schematic and finally have his schematic "grounding scheme" drawn and implemented correctly. How about it?

Otherwise, he just might get caught up in a "Ground Loop" of constant schematic changes and updates!!! (Low-level humor intended).

/

 

[DaveP]

RCA Grounding Instructions

Any amplifier having two or more stages should be constructed with a straight-line layout so that maximum separation is provided between the signal input and output circuits and terminals.

Power-supply connections, particularly those carrying ac, should be isolated as far as possible from signal connections, especially from the input connection. Signal-carrying conductors, even when shielded, should not be cabled together with power-supply conductors.

Internal wiring for ac-operated tube heaters, switches, pilot-light sockets, and other devices, should be twisted and placed flat against the chassis.

All connections to the ground side of the circuit in each unit should be made to a common bus of heavy wire. This bus should be connected to the chassis only at the point of minimum signal voltage, i.e., at the signal-input terminal of the unit.
best
DaveP

 

[Estomagado]

That book is quite easy to find online, even sowter has parts of it somewhere on it's website.
Complete book
Sowter

OOOoh, I did download it before it vanishes.
Thank you!

 

[C.B. - Boudio]

Bootstrapped cathode followers and grounding updated. Is this more like it?

 

[MidnightArrakis]

Is this more like it?

[Is this more like it?] -- Assuming that your schematic is a KiCAD schematic, how about if you send me your KiCAD file in a PM?

P.S. -- Do you know that -- KiCAD 9.0 -- was just released on February 20th?

/

 

[DaveP]

Is this more like it?

Looking good, but don't forget to connect the grounds of the EC92's to the rest of the earth busbar.
best
DaveP

 

[C.B. - Boudio]

Looking good, but don't forget to connect the grounds of the EC92's to the rest of the earth busbar.
best
DaveP

They are connected (to the right of the left EC92).

 

[DaveP]

So they are, my mistake.
best
DaveP

 

[ruffrecords]

[This is not reflected in your schematic] -- It may be helpful to the OP if you provided either a hand-sketch or a KiCAD-sketch of how things are supposed to be so he can more easily "see" and understand the concept you are attempting to convey. That way, he can then update his schematic and finally have his schematic "grounding scheme" drawn and implemented correctly. How about it?

Otherwise, he just might get caught up in a "Ground Loop" of constant schematic changes and updates!!! (Low-level humor intended).

/

This is explained in detail in my Grounding 101 document which I have posted here numerous times.

Here it is again

Cheers

Ian

 

[MidnightArrakis]

This is explained in detail in my Grounding 101 document which I have posted here numerous times.

[This is explained in detail in my Grounding 101 document] -- GREAT!!! I figured that you would probably have some detailed document about "Grounding" somewhere on your website, which is why I made reference to you in my response!!! YA-A-A-YY!!!.....

In some distantly related news.....take a look at this 8-minute video that details a rather amazing "Panel Designer/Maker" program. This program has some features for creating rack-panels with XLR connectors, while also getting all of the graphics and text aligned and centered, that even my SolidWorks Premium program doesn't have!!! As an example, this video shows you a 1U and a 4U rack-panel with several XLR connectors placed on them, viewed from the front. When you flip the panel over and view it from the rear, the program even displays the XLR pin-numbers, so you don't end-up connecting the wiring up to the wrong pins!!! How cool is that???



>> I just might have to buy this program!!! You can even design complete 19" racks of equipment and include all of its wiring as well.

In addition, the company that has developed this software program is also based in your neck-of-the-woods, there in the UK!!!

/