LM723 replacement

[moamps]

Tube HT supply. Rough smoothed 300V dc input. 250V at up to  300mA regulated very low noise output. By very low noise I mean ripple in the micro volts (on the order of 90dB ripple attenuation).

Maybe the HT power supply from  SSL 4000 for plasma displays is a good candidate to start with.

 

[ruffrecords]

Oh geez, yet another part in the latest 3rd Edition of "The Art of Electronics" dies. The others I was looking for from the book were JFETs.

The chapter on power supplies just happens to be available as the "sample chapter" and the guys seem to like this venerable part:
https://artofelectronics.net/wp-content/uploads/2016/02/AoE3_chapter9.pdf

The "Power One" and other open-frame linear supplies all seem to use this part, it seems a good idea to stock up just for repair/replacement use.

Yes, the international Power 250V at 100mA linear power supply uses one (and a 2N3055 pass transistor). If only they did a 300mA version I would be a happy bunny.

I forgot about AoE. It came out after left uni so my standard textbook was Alley & Atwood which still had some sections on tubes.

Thanks for the link - the LR8 based HT supply is very interesting. Looks ideal. I was just wondering if an LR8 could be beefed up and there it is in H&H.

Cheers

Ian

 

[PRR]

> my standard textbook was Alley & Atwood which still had some sections on tubes.

2nd edition:  https://archive.org/details/ElectronicEngineering

Chapter 1 is "Electron Ballistics"

A good introductory or refresher book.

Later editions:
https://www.amazon.com/Electronic-Engineering-Charles-L-Alley/dp/0471024503

 

[ruffrecords]

> my standard textbook was Alley & Atwood which still had some sections on tubes.

2nd edition:  https://archive.org/details/ElectronicEngineering

Second Edition is what I have on my bookshelf. I purchased it in 1970 for £3.10

Chapter 1 is "Electron Ballistics"

A good introductory or refresher book.

The last chapter, on power supplies, includes the curves for the 5U4

Cheers

Ian

 

[PRR]

While it is clearly based on Schade, this book's re-draw of cap-input rectifier curves is much easier to use.

I have added blue numbers for higher impedances, and highlighted several typical ripple goals. 5% is always a good choice. You find 1% on those hi-fi amps with soup-can caps. You find 15% on huge affordable guitar amplifiers, especially older jobs.