Blimey, I'll need another mortgage. 😱
I could buy a set of valves for that price. (Er, have done)😉
I could buy a set of valves for that price. (Er, have done)😉
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yay! An excuse for a Kindle purchase rolled into the deal! Woohoo! Christmas is certainly here...
Newnes uses Elsevier Direct for international distribution. They still show it as unpublished. I did find a UK source when I looked around yesterday but I can't find it now. I will just wait for Amazon.
Morgan emailed me about two years ago asking if he could include some PowerDrive information. I have no idea if it made the cut though.
Paper or Kindle.......I don't want to get my wifes Kindle too close to the workbench due to the probability of it getting broken. On the other hand the paper copy of the third edition started losing pages within a few months. My original 1973 edition RCA tube manual is in better shape.
From what hes told me, yes, Power Drive is in there. I chided him a bit about dismissing AB2 in the 3rd edition and apparently he took me seriously.
Now that you have introduced Morgan to AB2, do you think you can get screen drive into the 5th edition?
I have the third edition and "Building Valve Amplifiers" by Morgan Jones. Are there any other books a newbee like me should read?
You have the "Building Valve Amplifiers", there is also one called "Valve Amplifiers" by the same author.
Let's hope for better/more binding glue this time around.
Heyraz: "Valve Amplifiers" is where most of the theory is. "Building Valve Amplifiers" is the construction tips and methods sidekick book.
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It ought to be, dammit. It's a very interesting approach toward efficiency. First one I ever saw was the Audionics from the '70s.
Darn, something must be going on, cannot find any availability on ebay or amazon. That ebay seller is listed as 'This seller is currently away, and is not processing orders at this time. You can add this item to your watch list to purchase later'.
😡
The official release date in Jan 4 in the US. None have been seen for sale here. They seem to be available off and on in the UK, but you are even further from the source than I am......
Screen drive implies that the audio drive signal is applied to G2 instead of G1. You won't find it in tube books, and it is sill relatively experimental. There have been a few commercially made screen drive amps (Berning comes to mind).
Screen drive has the major advantage of high efficiency. This can be exploited to get big power out of small tubes. The disadvantage is that very large drive voltages are required with grid current being drawn. It is easy to over dissipate the screen causing a fireball inside the tube.
Here is the schematic for an experiment I made several years ago. It is also at the bottom of this page:
6AV5GA testing
Search through the "tube sale at AES" thread. Some screen drive experiments there sucked 125 watts out of a pair of 98 cent tubes for a while until I tried to get more blowing the screen grid out of the tube.
Screen drive has the major advantage of high efficiency. This can be exploited to get big power out of small tubes. The disadvantage is that very large drive voltages are required with grid current being drawn. It is easy to over dissipate the screen causing a fireball inside the tube.
Here is the schematic for an experiment I made several years ago. It is also at the bottom of this page:
6AV5GA testing
Search through the "tube sale at AES" thread. Some screen drive experiments there sucked 125 watts out of a pair of 98 cent tubes for a while until I tried to get more blowing the screen grid out of the tube.
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