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Ham Radio in China -- Interesting info from 高倧伟 David Cowhig

βœ‡SolderSmoke Daily News
By: Bill Meara
27 May 2024 at 16:29

Chinese Radio Licenses and Operating Certificates

David Cowhig (aka WA1LBP,Β  aka Gao Da Wei) was Hambassdor for 73 Magazine on Okinawa when I held a similar "position" on the island of Hispaniola.Β  David is a real Asia hand, and is fluent in both Mandarin and Japanese.Β  Β He is uiniquely sitated to provide info on ham radio in China.Β  In a recent post he provides this info, and describes how we may soon be hearing from ham Taikonauts in space:Β Β 

https://gaodawei.wordpress.com/2024/05/22/2024-ham-radio-in-china-soon-chinese-hams-in-space/

Thanks David!Β 

CuriousMarc Looks at Phase-Locked Loops (PLL)

βœ‡SolderSmoke Daily News
By: Bill Meara
15 May 2024 at 12:48

I really like Marc's (AL6JV) videos. It is great fun and very educational to watch him and his team troubleshoot some of the old gear they work on.Β  There is also a lot of humor.Β 

In this video Marc delves into the circuitry of the Phase-Locked Loop.Β  I didn't know that the PLL circuitry has its origins in the space program.Β  NASA needed a circuit that would permit very narrow band reception of a signal that was undergoing the kind of Doppler shift that spacecraft produce.Β  Β Viola! Enter the PLL.Β  Far beyond Apollo, PLL circuits started to show up in ordinary radio gear.Β  The General Electric (and JC Penny!) CB transceivers that we rescued from 11 meter infamy used PLL as the frequency determining circuit.Β 

Marc gives a really good explanation of how the PLL circuit works.Β  Thanks Marc.Β 

However, Marc gives an incorrect pronuniation of "kludge" (it should sound like fudge).Β  But he is a computer guy and is originally from France, so all is forgiven.Β  He also redeems himself by making fun of the inaccuracies that appear in what he calls "data shites."Β 

Deep Space Station 43 -- Canberra, Australia

βœ‡SolderSmoke Daily News
By: Bill Meara
19 April 2024 at 09:52

Β 

https://spectrum.ieee.org/apollo-era-antenna-voyager-2

From the IEEE article:Β 

The dish’s manufacturer took great pains to ensure that its surface had no bumps or rough spots. The smoother the dish surface, the better it is at focusing incident waves onto the signal detector so there’s a higher signal-to-noise ratio.

DSS-43 boasts a pointing accuracy of 0.005 degrees (18 arc seconds)β€”which is important for ensuring that it is pointed directly at the receiver on a distant spacecraft. Voyager 2 broadcasts using a 23-watt radio. But by the time the signals traverse the multibillion-kilometer distance from the heliopause to Earth, their power has faded to a level 20 billion times weaker than what is needed to run a digital watch. Capturing every bit of the incident signals is crucial to gathering useful information from the transmissions.

The antenna has a transmitter capable of 400 kilowatts, with a beam width of 0.0038 degrees. Without the 1987 upgrade, signals sent from DSS-43 to a spacecraft venturing outside the solar system likely never would reach their target.


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