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Messages - Charlie_Dont_Surf

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61
Latin American Pirate / Re: UNID 6935 AM 0015 UTC 3 Nov 2023
« on: November 03, 2023, 0033 UTC »
I'm hearing some light modulation.

AD149? I'm in the middle of three other things and I don't feel like hunting around South American SDRs to check.

I can see something around 6940 KHz as well, which might be Zeppelin Radio from Greece. (I'm lazy about that too.) If so, propagation seems favorable tonight.

0040 - Male announcement between songs but unable to understand or even tell which language.
0100 - Phil Collins
0130 - Off, after Pink Floyd, "Hey You"

62
2300 - Strong carrier (S9+10) on the Vermont SDR but audio is incredibly weak. Just enough to perceive music but that that's about it.
2321 - I can tell they are playing "Eminence Front" at the moment but audio is still barely perceptible.
2348 - I had to step away for the last 25 minutes or so. Yes, modulation is a lot better, but seems to vary with time. Here's a spec plot from one of the moments of strong modulation, which shows a good level with sidebands ~ -25 to -30 dBc, which is perfect.



2349 - ID. I can hear some distortion and that tells me that the op has turned things up to about the point where you want to stop.  :D
2354 - Audio is weak again.
0003 - ID then into Motown ?
0011 - Rainbow, Stone Cold. Audio is still weak, probably comparable to 2321 UTC.
0023 - SSTV
0025 - TX off.

63
North American Shortwave Pirate / Re: UNID 7320 AM 0311 UTC 1 NOV 2023
« on: November 01, 2023, 0327 UTC »
Similar to Rob Rich, 7315 (not sure what it is, but it is transmitting in Arabic) is just destroying 7320 on the Vermont SDR. In SAU mode with PBT manipulated, I can hear classical music but that's about it.

64
General Radio Discussion / Re: The Myth of the War of the Worlds Panic
« on: November 01, 2023, 0304 UTC »
My father was 21 years old at the time. He said that he did not hear the broadcast either but remembers hearing about it the day after. He said that it wasn't like there were people running through the streets or anything close to that where he lived.

At the same time, I question the authors closing:
Quote
But the myth also persists because it so perfectly captures our unease with the media’s power over our lives. “The ‘panic broadcast’ may be as much a function of fantasy as fact,” writes Northwestern’s Jeffrey Sconce in Haunted Media, suggesting that the panic myth is a function of simple displacement: It’s not the Martians invading Earth that we fear, he argues; it’s ABC, CBS, and NBC invading and colonizing our consciousness that truly frightens us. To Sconce, the panic plays a “symbolic function” for American culture—we retell the story because we need a cautionary tale about the power of media. And that need has hardly abated: Just as radio was the new medium of the 1930s, opening up exciting new channels of communication, today the Internet provides us with both the promise of a dynamic communicative future and dystopian fears of a new form of mind control; lost privacy; and attacks from scary, mysterious forces. This is the fear that animates our fantasy of panicked hordes—both then and now.

I'm going to suggest that a lot of the dumb, false, hysterical crap that gets passed around on Facebook is a similar form of manipulation to a population that is willing to believe anything. One look at Snopes.com and Factcheck.org will show you how much of it there is. And I'm quite sure that there are more people being sucked in for this junk than ever got panicked in 1938. Just count reposts as some indication.

65
Huh? / Candy
« on: November 01, 2023, 0234 UTC »
WILL SOMEONE PLEASE COME OVER AND EAT ALL THE LEFTOVER CANDY?

That is all.

66
Huh? / Re: I hate Whisper ham radio
« on: November 01, 2023, 0234 UTC »
but the difference is that these are all "preemptable"

Oh, very nice. What did you have to do to make this work?

67
Love Scratchmoney's SDR, except tonight because it's "off the air".  :(  Much bummers.

Cool quad loop antenna. I want to build one like that.

68
0215 (approximately) - caught the end of an Iron Maiden song.
0219 - WREC IDs. Into Van Halen.
0226 - P.J. Sparks (Sparx?) on the mic, inviting us to "stay tuned for the next 40 minutes or so."

69
The RF Workbench / Re: NCP driver sucks
« on: November 01, 2023, 0047 UTC »
Yes, the NCP81074 does indeed suck for our purposes. I'm not planning to use it ever again.

It is simply not suitable for use at >6 MHz on anything with a Qg >~8 nC; you will blow the NCP81074. The reasons are:
1) The NCP81074 runs a high supply current at these frequencies, which dramatically increases its power dissipation.
2) It does not have an exposed paddle (called an "EPAD" in industry lingo) under its "belly" to allow you solder it to the PCB and get the heat out, which is absolutely necessary. (Most heat will come out of the belly since that is where the silicon die is attached to the package leadframe. Adding a heatsink to the top is not going to help much.)

You can get it to work and stay alive at lower Vdd (< 9 V) depending upon the transistor but then you can't drive many LDMOS, GaN and especially SiC transistors) to full on (lowest Rds_on), because the Qg needed to get the gate up to ~12 V far exceeds what the driver can deliver and not burn up. The demands upon the gate driver to source current (and thus dissipate heat) are significantly higher at 12 V than 6 V for example. Then when modulation of the final FET is added to the mix, the current demands at the gate increase again too. The NCP81074 can drive 4-6 A but it can't dissipate the heat that this causes when trying to do this at 6+ MHz, 50% duty cycle, Vdd = 12 V.

Keep in mind that the NCP is not characterized to work beyond 2 MHz. Obviously you can try it - we all do this - but understand that you may suffer unpredictable performance. Every time I have blown one of these up and soldered a new one down, I get a somewhat different supply current than the previous during operation. This tells me everything I need to know. You don't know what you are going to get the next time and the next time, etc, because you are working in conditions that are marginal and unintended for the chip. You likely won't see this at < 2 MHz because that is where it is spec'ed and intended to operate.

Instead, I have been using the Renesas ISL89163 dual driver or the TI UCC27614. Both have EPADs, can drive 6+ A and are plenty fast. (The ISL89163 can be paralleled for ~12A, the UCC27614 can do 10 A.) I haven't explored the TI chip much but I had the ISL89163 running at 18 MHz on a 28 nC gate Transphorm Cascode FET the other day and it looked like I still had extra pulse width to spare, i.e., the edges weren't so rounded that the pulse was horribly distorted. No self-destruction so far. 8) The ISL89163 has roughly half the supply current of the NCP81074 at the same frequency. Of course, these aren't spec'ed to operate at 6-7 MHz either, but so far I have not seen the same limitations as the NCP81074.

TI does make a FET driver that is intended to be used up to 50 MHz for LIDAR (LMG1025-Q1) but it can't go above 5 V.

70
Had to move to 4195

OK. Sounding good on the Vermont SDR. Reception is actually better than 6880.  8)
At some point I will put up my antenna in my yard and turn on the radio behind me. I'm still working this afternoon and sunset isn't for another hour or so.

71
Carrier lost at 2335 UTC.

72
Signal is quite loud on the K1VL SDR in Vermont at the moment, S9+ / SINPO 53554 because someone is sending CW ("CQ de..", etc.) underneath with what sounds like an older TX and a bit of hum.

2159: TX off.

73
2113 - Open carrier at the moment. Might be a difficult place to be given the expected QRM on both sides, unless they are just "holding their spot" for future use.

2212 (approximately) - programming starts in earnest with some laughter, etc.
2233 - Wellsville address given, said to be broadcasting from Salem, MA. Announcer has a distinct Massachusetts accent, for authenticity.
2240 - An audio story about the The House of Usher.
2245 - TX off, after witch cackling.

74
0130 - It's dusk and I can just barely detect a carrier out here at home. Listening on the Northern Utah SDR, SINPO 24222 / S7 with slight auroral flutter.
0134 - "Goodnight on behalf of Radio Halloween"
0136 - Ghostbusters
0139 - TX Off

75
Huh? / Re: I hate Whisper ham radio
« on: October 28, 2023, 0101 UTC »
"Don't hate the mode; hate the software"

WSPR is useful for trying out antenna changes and for checking out propagation paths. Having said, I do find it to be a drag that so many kiwi SDR channels are taken up with daemons.

Maybe after Halloween we can chase all the demons (and daemons) away....

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