John Curl's Blowtorch preamplifier part II

[FrankWW]

Originally Posted by bcarso

How wonderful! Do we know the dramatis personae?

Johnny Wayne, Frank Schuster and Sylvia Lennick

50 years since she said, 'Julie, don't go!' - thestar.com

Wayne and Shuster - Wikipedia, the free encyclopedia

[bcarso]

Originally Posted by FrankWW

Johnny Wayne, Frank Schuster and Sylvia Lennick

50 years since she said, 'Julie, don't go!' - thestar.com

Wayne and Shuster - Wikipedia, the free encyclopedia

Excellent! Thank you. I must have seen that the first time it was on network TV. A long time ago, indeed.

Clearly, it made an inedible impression on my young mind.

[john curl]

Everyone, could we go back to audio design? I realize that some don't think it very useful or important, but it is the reason for the length and attendance on this thread.
In my world, today, I have several assignments:
One is to replace 2SK389's with 2SK170's or LSK 170's. This requires some sort of matching scheme to get good offsets, that is a 'piece of cake'.
The next is to troubleshoot a serious phono stage design with about 50 jfets per channel, sorry I can't get into detail about that.
Third, is to design an op amp containing headphone amp of high quality. We can talk about that, and WHY I did it the way I did.
Any questions?

[PMA]

Originally Posted by simon7000

Actually Ramona caused a bit of a stir when it was first tested. It seems the transmitter bounced off the Ionosphere and was picked up on all sorts of gear in the U.S. leading folks to wonder if it was some sort of deliberate jamming or electronic warfare!

It was completely passive system, with no transmitter. There is some description in

http://www.raf.mod.uk/rafcms/mediafi...86AD92DC17.pdf

article "Silent Trackers: The Spectre of Passive Surveillance in the Information Age"

[Bonsai]

"Third, is to design an op amp containing headphone amp of high quality. We can talk about that, and WHY I did it the way I did"

I'd just come clean and say if you are after top quality its really a no brainer.

[DF96]

I remember the surprise when the Serbs shot down a US stealth bomber. At the time it was said that they were using passive radar based on broadcast transmitters. A stealth bomber may be 'invisible', but it is still opaque.

Underestimating your enemy seems to be a standard military tactic. Are people taught to think in straight lines at staff college, or is it that the armed forces only recruit unimaginative people?

[PMA]

Originally Posted by DF96

Underestimating your enemy seems to be a standard military tactic.

Not only military tactic - this thread is a real proof. I would not speak about 'enemy' in this thread, but actually underestimating of potential competition or of different design approach is a standard tactic here, rather than open unprejudiced discussion. And for this reason it lost any attractiveness regarding audio design.

[VladimirK]

Originally Posted by john curl

The next is to troubleshoot a serious phono stage design with about 50 jfets per channel, sorry I can't get into detail about that.
Third, is to design an op amp containing headphone amp of high quality. We can talk about that, and WHY I did it the way I did.
Any questions?

Do you plan to make phono stage integrated with high quality headamp?
That would be new, a system including no digits, only vinyl and high-quality low-wattage analog schematics.

[john curl]

I have been making phono preamps for the last few years. However, I can only talk in general about the designs, because they are not even released yet.
I feel a little differently about the headphone design, because it is a Honda and not a Porsche.

[simon7000]

Originally Posted by PMA

It was completely passive system, with no transmitter. There is some description in

http://www.raf.mod.uk/rafcms/mediafi...86AD92DC17.pdf

article "Silent Trackers: The Spectre of Passive Surveillance in the Information Age"

Apparently either during development they used a simulation of US AWACS or there was some other source. At the time it was called in the U.S. "Mocking Bird" and thought to Soviet over the horizon radar.