Search found 3705 matches

by JR.
Sat Dec 26, 2009 8:05 pm
Forum: The Peabody Lounge
Topic: Texas White Chrsitmas
Replies: 3
Views: 7384

Re: Texas White Chrsitmas

I had a dusting in MS a few weeks ago, but it melted with the morning sun.

But then again it is winter.

JR
by JR.
Sat Dec 26, 2009 8:03 pm
Forum: Pro Audio Design
Topic: PSU design assistance needed
Replies: 35
Views: 52706

Re: PSU design assistance needed

Please read my post about the TS-1 PS

While that was dealing with a relatively high current 5V supply, powered from a higher voltage winding. If the 5V supply is low current, it doesn't really matter.

JR
by JR.
Sat Dec 26, 2009 10:09 am
Forum: The Peabody Lounge
Topic: Texas White Chrsitmas
Replies: 3
Views: 7384

Re: Texas White Chrsitmas

http://www.politico.com/news/stories/1108/15931.html Be on the lookout for a visit from Al... we got a ton of rain.. if it was snow, it would have been a significant accumulation. But I haven't seen more than a couple inches, if every snow was added together for the few decades I've lived here. I st...
by JR.
Sat Dec 26, 2009 9:32 am
Forum: Pro Audio Design
Topic: PSU design assistance needed
Replies: 35
Views: 52706

Re: PSU design assistance needed

Why the extra diode from regulator output to ground on each leg (D7 & D10)? The extra diodes may be over kill but they are to prevent latch up, during transient start up conditions. With some older regulators when one supply comes up first, the other can latch in a reverse bias and be damaged, ...
by JR.
Thu Dec 24, 2009 4:42 pm
Forum: Pro Audio Design
Topic: PSU design assistance needed
Replies: 35
Views: 52706

Re: PSU design assistance needed

Yup, the 120 or 130 ohm value doesn't matter much (its the ratios), but those spare diodes thrown in will muck up things, and it does matter which order they are in..

The fixed R generates a reference current, the current creates a voltage drop across the variable R.. get thee to an app note...

JR
by JR.
Thu Dec 24, 2009 10:42 am
Forum: Pro Audio Design
Topic: PSU design assistance needed
Replies: 35
Views: 52706

Re: PSU design assistance needed

Wayne- I didn't find my VR book in a quick search of several book shelfs... I have a pile of such stuff you might find interesting.. I'll talk to you off list about this, but I value what you are doing in archiving all this very good but obscure information, that served us so well when we were learn...
by JR.
Thu Dec 24, 2009 10:26 am
Forum: Pro Audio Design
Topic: PSU design assistance needed
Replies: 35
Views: 52706

Re: PSU design assistance needed

Thanx.. the trick PS is in the upper left hand corner.. IIRC I gave the 5V 3-terminal regulator it's own roughly 10V unregulated supply so it wouldn't drop out of regulation with ripple. A significant power savings from the nominal 20V unregulated. One perhaps unobvious part of that circuit, is that...
by JR.
Wed Dec 23, 2009 8:54 am
Forum: Pro Audio Design
Topic: PSU design assistance needed
Replies: 35
Views: 52706

Re: PSU design assistance needed

+1 that's a classic, was that the one with the green cover? I also vaguely remember a classic treatment in one of those old national books about heatsinks and thermal resistance relationships, junction to ambient, et al. Of course to add a little esoterica to the mundane. In my TS-1, which I think h...
by JR.
Mon Dec 21, 2009 4:13 pm
Forum: The Peabody Lounge
Topic: The Mad Tea Party: free xmas single
Replies: 1
Views: 5459

Re: The Mad Tea Party: free xmas single

Merry Christmas...

FWIW I preferred the "cold outside track"

Not quite ready for prime time, but they be songs there...

JR
by JR.
Thu Dec 17, 2009 10:46 am
Forum: Pro Audio Design
Topic: Sum bus theory and practice
Replies: 37
Views: 55215

Re: Sum bus theory and practice

I'm using Safari, and no it doesn't jump to page 4. It just opens to page 1. Funny to see that old paper written by Larry Blakely.. He was a marketing type and OK technical writer, but not an engineer...(I guess a recording engineer, but not design engineer). They say the BP of SVF is only 6dB/oct w...