Pro Audio Design Forum

Heres' the LM317/337 regulator board schematic we sold for the Picos. They are no longer available but it may help you out: http://www.proaudiodesignforum.com/PicoComp/PCB-Kits/Documents/PSU/PSU_Documents.htm I had forgotten that there were links to Sam Groener's PSU calculator spreadsheet and to th...

We estimate it's been about 52 years since the last white Christmas...

Thanks John! I'm archiving some physical databooks for our member crazynightowl as well. I think I have the VR handbook. Let me see which edition I have...

BTW The National Audio Handbook edition I have is 1977. I think I have an earlier one as well.

John - The NSC Audio Handbook I have is the series with the dark blue bottom and - IIRC - a tan color bar at the top. Unfortunately the NSC books of that era were printed on newsprint and they haven't aged well. I'm not sure where we discussed the TS-1 but I do have the sch here: http://www.proaudio...

This is a very good reference for you to start with. It should be on everyone's virtual bookshelf:

http://www.proaudiodesignforum.com/imag ... Design.pdf

National Semiconductor Audio Handbook Chapter 6 Power Supply Design

For now, jump here: viewtopic.php?f=6&t=26&p=101

And here: http://www.ka-electronics.com/Images/pd ... pdf#page=4

JR - What browser do you use? Do the pdf page arguments work in Safari?

Paul - Use a "derived" filter so that they re-combine properly. The old NSC audio handbook has a discussion on that in active speaker crossovers. We should probably start a thread on that.

Wayne

An assumption definitaly not to make is to assume that the carbon comp resistors really are the correct value in 2010.

I just threw out a bunch of 5% carbon comps that were off in the 20-30% range. Others from the same period, depending on value manufacturer etc., were spot on.

Doug - What John said. Old school electrolytic caps had the outer metal case connected to ground, new school caps not so much. You might still want to determine which terminal. + or -, is the outer wrap even though the can floats. (I think you'll find it to usually be the - terminal.) I found large ...

I had wondered about eliminating the coupling caps. I think "might" might have been the wiggle word. I suppose you could say that the virtual ground needs to be "virtual" at DC too.