ODS Eyelet Boards

[martin manning]

Sounds like Tony has some on the way.

[martin manning]

Added rectifier board with bipolar supply for SSS CF driver tube to first post.

[Raoul Duke]

Might be a silly question - but after scrolling through and reading this thread half a dozen times I was wondering if the main board layout on page 3 of the bigger attachment was actual size to transfer to board material when printed out?
Apologies if I missed it - but I don't think I did?

Thanks and regards!
RD

[Guy77]

Might be a silly question - but after scrolling through and reading this thread half a dozen times I was wondering if the main board layout on page 3 of the bigger attachment was actual size to transfer to board material when printed out?
Apologies if I missed it - but I don't think I did?

Thanks and regards!
RD

If it helps any I printed out that same preamp board on the 3rd pg and I scaled it to 8.5 in by 3in and it worked great for me. So my actual preamp boards measures 8.5in x 3in. I attached a pic of one in a 19x8x2.5in chassis that I am building now.

20230927_171445.jpg

G

[martin manning]

Should be actual size. I thought I had listed the board and mounting bolt centers, plus the eyelet count there but I guess not. When I get home (in a few days) I’ll check and add those dimensions to the drawing.

[Raoul Duke]

Thank you both for the info, very much appreciated!

[martin manning]

The ODS boards .pdf has been updated to consolidate the several files that were in the first post. The preamp board is now shown populated with components for both the 4th/5th Gen and 2nd Gen ODS circuits. The all-axial capacitor eyelet board patterns are the same as the original set posted here, which are available pre-made in the For Sale/Trade section from Amplified Nation.

[dbharris]

That is great Martin, thank you! This thread should really be a sticky.

For the 2nd Gen layout, compared to the sticky layout in the files section I noticed a couple differences with respect to the phase inverter. The plate resistors in the layout are 47K and 51K and the bias resistors are 100K.

-Dan

[martin manning]

Thanks Dan, I can change the output grid leaks. Showing the components is mostly about how to get the 2nd Gen circuit on the same board. I did adjust the PI plate loads down to compensate for the presence of the trimmer, though. Comments are welcome, of course.

[martin manning]

Made a few changes to the axial-radial power supply board conversion drawing for clarity. The purpose of that is to show how a pre-made axial cap board is converted to the "Precision" style PS using only a hand drill.

[Raoul Duke]

This is pretty impressive!
The detail and explanations are really easy to follow and very well done.
Even a feller with no electronics background can make sense of it all.

Thanks Martin!

[martin manning]

Last iteration. Same PS board design for axial or radial filters, and axial or snap-in reservoir. The pre-made PS board works for all. Snap-in caps are offset to make room for 30 mm diameter cans. This opens more options and allows for larger capacitance if desired (some ODS had 2x 300u).

[martin manning]

Added a document showing component layouts for several generations of ODS using the same preamp board. The document was created by JBorders, and is posted elsewhere on the site, but added here for easy reference. Also moved B+2 & 3 ground eyelet on the main power supply board.

[martin manning]

Another ODS board .pdf update:

- The voltage doubler relay power supply board is now shown using the same hole pattern as the original FWB board. The board sold by Amp Nation, which matches the FWB board here, can be configured as a doubler in this way.

- The all-radial cap version of the relay power supply with board-mounted regulator has been reworked so that it can also be configured as either a FWB or as a voltage doubler.

- The main filter board shows a conversion to either partial radial (Precision-style PS) or all-radial caps. I've sent a note to Taylor suggesting he could punch the extra holes in the board he is offering to accommodate either axial or radial cap configurations without any rework.

- A Bluesmaster preamp board configuration has been added showing HRM connections.

- Relay connections for 2nd Gen "Level" MV have been added.

[pfarrell]

Amazing work Martin—Thank you!