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VHF/UHF noise source


 

This issue of QST is available here:
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John?? VE3CXB


 

Being an old HP uW SE, the 346 A noise source is 10 MHz to 18 GHz. You get that range for a mere $4000 but it is flat!

Dan Kahn
On Sunday, November 24, 2024 at 03:36:18 PM EST, wn4isx via groups.io <wn4isx@...> wrote:


Thank you!?
Several years ago the ARRL made Disney look like "let all our movies and cartoons be free."
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Remember when Disney went after daycares across the nation for showing VHS tapes of Disney cartoons?
My wife's nephew and niece daycare received one of the "you owe us a gazillion dollars."
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The ARRL went bonkers when someone released some of their 1950s handbooks in ?1990?.
I wonder how Internet Archive avoids serious copyright issues.
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I'd hate to be a popular author because dealing with copyright and the Internet would be whack a mole.
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It is better to use a LM317 or 338 instead of a variable resistor to control the light bulb.
And a 12V VW cabin bulb offers higher frequency noise output. A straight filament is better then a coiled filament.
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There are better VHF/UHF noise sources like commercial noise diodes which are rather expensive.
There are also "noise vacuum tubes." I have two in route, I have some doubts but I'll give them a try.
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BTW, I just saw a review of the new Cad CTS. One option is a 6 speed manual trans!
Dan K
On Sunday, November 24, 2024 at 05:08:30 PM EST, wn4isx via groups.io <wn4isx@...> wrote:


Oh sure, I'll pick one up after I snag a Lotus standard shift car. [There are very few standards being made today.]?
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Right after an air force transport jet drops a ton or so of gold in our backyard.
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Though 18GHz is slightly above my frequencies of interest.
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Although I did get to play with an analog Ku satellite uplink/downlink, I sent a 1kHz sine wave derived from a crystal controlled oscillator, converted the square wave to a nice, low distortion sine wave.
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I fed the input to the TX and output of the RX into X/Y of a scope. The Lissajous Figure showed a slight constant change in phase. I have a Betacam (not home Beta, professional video) tape with uplink audio in one channel, downlink in the other and the image of the scope on video. I don't have access to a Betacam VCR so the data is all but lost. Such is life.
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?But a 18GHz noise source....a bit beyond my needs and clearly beyond my means.
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