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Messages - redhat

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61
FM DX Loggings / Good E-skip opening this evening 4-16-2020 0000z+
« on: April 16, 2020, 0240 UTC »
For fear of incrimination I will not list calls, but did observe many FM signals this afternoon, some of which overpowered LP rimshots.  I verified 4 stations, all around the 1K mile mark as heard on the factory radio in the mobile unit in a parking lot on a hill.  I alerted a friend of mine to the action, but have yet to hear back on his listening session.  He did note some activity last night, but signals were too weak to demod.  As expected, condx returned to normal around sunset.

+-RH

62
The RF Workbench / Re: Simplest Tx
« on: April 12, 2020, 2301 UTC »
Quote
And oh look: I just noticed that the Cree SiC device has an internal 26 Ohm gate resistance already. Gate resistance that high is not inherent in SiC technology; they added some resistance to the device inside the package. I'll give you one guess as to why they did that. This reinforces my point. Adding more externally would help protect (given the caveats above) but obviously the need is reduced in this case. I still don't like the idea of blowing up the internal gate resistor and wrecking the whole device when I could have done something about it.

I don't think this is quite true.  The gate resistance is usually caused by the lossy-ness of the semiconductor material and the very fine binding wires used to connect the die to the outside world.  You'll notice on most datasheets this is derived by measuring the AC resistance of the junction at a known frequency and amplitude.  The larger the die and its gate structure, the larger the parasitic gate capacity, and the higher the gate AC resistance.  This is dependent on which silicon technology and topology is being used, obviously.

I can't speak with any authority on other technologies, but the metalization of the gate structure in SiC is one of the reasons for the higher gate resistance than comparable Si devices.

+-RH

63
Equipment / Re: Loop or Longwire?
« on: April 03, 2020, 0147 UTC »
*Cue Chris Smolinski...

A loop AFAIK will have lower noise than a long wire, although lower overall sensitivity.

+-RH

64
Huh? / Re: Slow boat from Sweden?
« on: March 31, 2020, 0119 UTC »
I got a similar result trying to order toner cartridges for my printer...yikes!

+-RH

65
I got one of those Greek C-QUAM transmitters recently and will be doing a youtube video on it soon with partial stereo proof-of-performance measurements.  Its based largely on the Chris Cuff design.

+-RH

66
Huh? / Re: Corona Virus panic buying...
« on: March 26, 2020, 0529 UTC »
Good to know the stupidity does not exist just in the US.  I blame social media and all the sheep that follow it...but I could be wrong, or simply jaded.

+-RH

67
General Radio Discussion / Re: Radio during and post pandemic
« on: March 20, 2020, 1549 UTC »
I've heard similar things here, as well as some folks in public radio working from home.  It should be mentioned that a lot of air shifts are being voice tracked (pre-recorded) these days anyway.
+-RH

68
General Radio Discussion / Re: Coronavirus Update Jingle Package
« on: March 17, 2020, 1817 UTC »
Now if we could just get them to do one for the beer report....wait they just did!

+-RH

69
Amateur Radio / Re: Thoughts on HF verticals
« on: March 17, 2020, 1708 UTC »
Most HF verticals (multi band) are substitute dummy loads, careful consideration and lots of time spent reading reviews on them are required before parting with your hard earned money. 

Lossy traps are an issue, some have ground radials (a bit better performance wise) which require some space in your back yard.

Butternut, Diamond and Cushcraft seem to be the key players in this field, personally, I don't have much time for them. 

See what the "leading" DXpeditions use and go from there... 8)

Monoband verticals have been very good to me.  I've never seen a multiband vertical that worked well, however.

+-RH

70
MW Loggings / Keep your ears open this week.
« on: March 17, 2020, 0836 UTC »
Under a declared national emergency, some stations may elect to run non directional at daytime power during overnights.  I'm hearing some of this now.

+-RH

71
Huh? / Re: Al, you being our expert...
« on: March 16, 2020, 2208 UTC »
Quote
No, they do not have knees. In fact, they do not even have legs; their pelvis rests directly on their feet, which accounts for the odd waddling motion when they walk on land.

Must make for some very cold fiddlybits in that climate...

+-RH

72
General Radio Discussion / Re: No More Political Posts, Please
« on: March 16, 2020, 1923 UTC »
Agreed.  Your daily dose of paranoia can be found elsewhere.  This is where I come to escape.

+-RH

73
Huh? / Re: Charleston Hamfest CANCELLED this SAT March 14TH!!!!
« on: March 13, 2020, 0929 UTC »
I would expect to see similar events cancelled in the coming weeks and months.

+-RH

74
This was a hypothetical idea of placing a transmitter off grid and using 4G to get an audio stream, process, and transmit the program material.  An arduino certainly does not have the horsepower to do that.

+-RH

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