The AM Forum

Hi Guy's, I'm looking for an on line site where I may be able to find high power public address systems that employed 810's 813's 811A type tubes or a book source for same. All schematics on other high power tubes are also welcome.


Thanks Terry

Here's a basic schematic for a 304TL audio amplifier:
http://www.alumrocktech.com/drawings/schematic-1bit.shtml

and more info:
http://www.alumrocktech.com/amplifier.shtml

 Here is a site with the Riders PA Manual online.
http://www.theused.com/resource/resource.php?curPage=0
 Look at the Altec and RCA Amplifiers. There are also some others of interest but those two have a couple of big ones.

Bill, KB3DKS in 1 Land

Hi Terry,

I have found some interesting tube schematics here:

http://www.freeinfosociety.com/electronics/schempage.php?cat=1

http://www.schematicheaven.com/hifi.htm

http://www.drtube.com/audioamp.htm

I have not looked too deeply into this list of links, but it might be fun to browse for high power audio schematics. It looks like quite a collection of stuff:

http://www.educypedia.be/electronics/tubesamplifiers.htm

73,

Rob W1AEX

And you can have one ready to use for a mere $85,000 !!!

I remember the audio amp used at one of the old drive-in picture shows, where they had a little speaker for every car.  The amplifier used a pair of 805's in class B, and the output transformer was about the size of a 300 watt modulation transformer.

The audio sounded extremely crappy, about on par with slopbucket.  But I don't think that really mattered because most people who came to the drive-in didn't pay much attention to the show anyway.