We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations. Always consult with the appropriate authorities if you have questions concerning what is permissible in your locale.

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Topics - ThaDood

Pages: 1 2 3 4 [5] 6 7 8 9 10 11 12 13 ... 42
61
https://blog.vinu.co.in/2018/03/ultrasonic-audio-transmitter-and.html?m=1     I know... Folks are going to tell me that the US Navy has been doing this for decades for underwater COMM's. However, I've wanted to do this over land. The last time that I did was nearly 25 years ago, and that project went up in smoke, literally. In theory, ultrasonic sound waves, (US), would propagate very much like RF microwaves, except any flat surfaces would reflect them, not just metal. That also means that rough and porous surfaces would be just as absorbent and attenuating. Still, the idea of putting US transducers, on solid satellite dishes, and bouncing signals to someone off of water towers, buildings, VERT mountain peaks, and even airplanes, just sounds like a fascinating concept to me. One other factor is the lag time of US from point 'A' to point 'B'. That, can be calculated. And, elevation... US will travel further at sea level's 14.7psig, than at a high elevation. Also in theory, rain scatter is possible with US, as it is with RF 10GHz, and above. Anyone will to try this project?

62
Huh? / Amateur Radio and a High School FM Station? Sure!!!!
« on: February 20, 2025, 1923 UTC »
https://www.radioworld.com/news-and-business/kent-county-md-high-school-students-command-the-hf-bands    Boomer, alerted me to this RW rip. Wow... Pretty hefty power for a school station on the FM-side.  https://radio-locator.com/cgi-bin/finder?sr=Y&s=C&call=WKhs&nav=home  Man... Wish that we had stuff like this when I was in high school. It was proposed, but all the faculty wanted was the ability to try and get grant $$$$'s. (Um, yeah...)
(Hey Chris!!!! Can you get either this FM station, or ever heard the HAM stations?)

UPDATE 3/4/2025:  Huh... Looks like ARN #2470 covered that as well for the 2/28/2025 release. https://www.arnewsline.org/

63
https://archive.org/search?query=collection%3A73-magazine&sort=-publicdate    One of the best MAG's, in my opinion, for INFO in Amateur Radio, and electronics, was Wayne Green's, 73. As a teen, I had a leaving B.O.C.E.S. electrical instructor give me a whole box of these in 1985. (I still have them.) Going through these is what started my education in electronics, radio, & antenna, theories. I still enjoy thumbing through these, albeit it is kind of sad to see advertised all the companies that are now gone today. Say what you want about Wayne Green, but he knew his stuff. And, if he didn't, he knew the people who did.  Enjoy!!!!

64
Huh? / A legit FM station on 87.7MHz? Really??? Franken FM?
« on: February 17, 2025, 1825 UTC »
https://radioinsight.com/headlines/292226/core-radio-group-launches-87-7-the-vibe-atlanta/     Interesting, if this FREQ is really true. A nice, clean, FREQ to be on, but just how many FM receivers in the USA can actually receive this? I-duh-know... It caught my attention. Am I missing something? In theory, you should be able to listen to this on an analog, NTSC TV, with mechanical TV channel tuner. Albeit, the audio maybe loud and distorted, with TV audio deviation being +/-25kHz, to FM BC's +/-75kHz. 
UPDATE: This could explain it, a Franken-FM.   https://en.wikipedia.org/wiki/Channel_6_radio_stations_in_the_United_States


65
Huh? / New Options for Pirates and LPFM? Another RW rip.
« on: February 14, 2025, 1743 UTC »
https://www.radioworld.com/columns-and-views/new-options-for-pirates-and-lpfm     Actual, stumbled on this one on my own. (Oooooooooooooo...)

66
Huh? / The History of UHF TV in America?
« on: February 11, 2025, 2105 UTC »
Being one who's worked for a UHF TV station, for like 7 years, I can appreciate this site.    https://uhfhistory.com/index.html

67
Equipment / Stripped-down Nextel-like HT's? Well, at least intriguing.
« on: February 06, 2025, 2002 UTC »
https://rapidradios.com/?view=abconvert-index-WU8xc6vs   I've heard about these advertised on C2C AM, and I've had friends ask me just how would these work? My guess was right, they won't work in a totally dead cell area. There are like a stripped-down version of how Nextel made their cell flip-phones with that Walkie-Talkie function. That said, they do seem to offer a VHF / UHF HT.  https://rapidradios.com/products/my-emergency-radio-emergency-vhf-uhf-radio  Doesn't seem to be much INFO on these, but must be like Beofangs? (Speculating here...) Still, intriguing...

68
Huh? / More RW rips on AM Boosters and AM Noise Levels? Um, yeah...
« on: February 05, 2025, 1816 UTC »
I don't subscribe to Radio World, but apparently Boomer does. And, when he find interesting stuff e-mailed to him, he has a tendency to share those. What's nice about that is it filters down to mainly the most interesting articles, like this one on AM Sync Boosters.  https://www.radioworld.com/tech-and-gear/synchronous-ams-long-and-tortuous-history    BTW, on-FREQ Boosters have also been used on FM, but I don't hear about their use today anymore. Mainly, just the litter of off-FREQ translators.
The other article is a 'know-schytt Sherlock' conclusion that pretty much most of us would come to upon AM noise.   https://www.radioworld.com/news-and-business/nrsc-releases-details-of-am-band-rf-noise-study  This big difference, someone got paid to do this study, and we didn't.   

69
Since the 1990's, I've been advised to put 151.625MHz FM in my scanners, since that FREQ seems to have lots of various activity. Indeed, it does. So much so, it's surprised me that the FCC didn't make it one of the license-free MURS Band channels. The MURS Channels were taken from those licensed VHF High Band color-dot FREQ's back around 2002, but Red Dot FREQ 151.625MHz, wasn't one of them. Here, in WV, I know that the tower workers are working in the middle of the night, on that now empty 600ft TV tower a mile behind me. When I would hear them on 151.625MHz, super strong signal, sure enough, I would see LED flash lights going up & down that tower. More recently, I hear a lot of mobile traffic from RT. 64. I even heard what sounded like Japanese spoken on there. Now, I have to question, is this still even a licensed VHF FREQ in the USA?   https://forums.radioreference.com/threads/itinerant-freq-151-625.307176/       So, what do y'all hear on that FREQ?

70
Propagation / Letter: Sporadic E Affects TV Signals, Too? An RW rip...
« on: February 02, 2025, 1709 UTC »
Boomer, alerted me to this RW article.    https://www.radioworld.com/global/letter-sporadic-e-affects-tv-signals-too       I miss TV Sporadic "E" DX'ing, but can still do it on FM. Plus, Tropo DX can still be had on VHF High Band and UHF TV Channels. When you hear a band opening, like distant 162MHz Weather Stations, do a re-scan on your TV off-air, with an antenna. It might surprise you of just what you might see, and how far.

71
http://www.gbppr.net/scanner/dsp40/index.html   I bought one of these at a hamfest, in the late 1990's, for $5.00. I couldn't turn that down, since the components themselves are at least worth that. As with everyone else who has tried one, the results are not that impressive, but my take is that it's great for taking out HET's when someone tunes-up on the FREQ that you want to QSO on. Anyway, after sitting in a bin for like 20-some years, it was time to take yet another look at this unit, and see if there were any modifications to be done with it. Apparently so... I'm going to try these.

72
http://www.gbppr.net/lpfm/Low_Power_Radio_Broadcasting.pdf    Don't know why link is listed as LPFM, it's more LPAM, and then some. This dude knew his stuff, so download this, while ya can. Lots of good INFO on "How-to's!" in here.

73
Well, I can't afford to get an Icom IC-705, but those that have, have asked me how to do a MARS MOD to that rig. Not done so to that rig myself, (Yet...), I did a Startpage Search on the subject, and the most descriptive one that I've come upon is this one.  https://www.prc-77.com/2024/04/mars-modding-ic-705.html   The dude who wrote this does also mention MODS.DK, my original 'go-to' on MOD's, but I like how he meticulously lays it all out. So, will it work? I leave y'all with that responsibility on that one, as I pass the INFO on it, but I can not vow that this will actually work. (There, my disclaimer.) The newest rig that I've MARS'ed it, the Xiegu G90 SDR. So easy there, an SMT diode, with an arrow pointing to it. All my other rigs are older ones, with MARS done, for opening up the 60M, 5 Channel, Amateur Band. Well, except my Kenwood TS-2000X, AES did the MOD, but didn't tell me. Oh BTW, if you do successfully do the MARS MOD on the IC-705, there's a possibility that the auto-tuner may not work well on MARS FREQ's. I say that, since the TS-2000X's auto-tuner gets confused on 60M, wanting to toggle from 75M and 40M. The same with the companion auto-tuner for the TS-50S, the AT-50. Pure speculation on my part here, but it can't be bad speculation. Good luck!!!!

UPDATE:  Not confirmed, but apparently, those that have the Japanese Version of the IC-705 have to do a different procedure. Can anyone confirm this? 

74
https://www.qsl.net/kp4md/henry_30a02.htm      Try #2 to post this, and not have Firefox crash and Windows update at the same time. Anyway... I bought one of these 'lil VHF commercial High Band amp at a Horseheads, NY Mini-Fest, back in the late 1990's for like $20.00, when the fest was at end and vendors were doing last minute close-outs. Hey, the parts were worth at least that. However, I've yet to power up and put RF to it to see if it even works, and to also see what FREQ it was tuned-up to. So, in a storage bin it's sat in for like +25 years. I did try a search for this amp over 20 years ago on-line, and could find nothing about this amp, at the time. Well, a few weeks ago, while searching for something completely different, that preceding link came up. (Well, COOL!!!) Not only that, but apparently, Henry Radio is still around today.  https://www.henryradio.com/  Anyway, back to that Henry 30A02 Amp, it looks very straight forward and has a nice filtering section. Better, than like Ramsey, or Mirage, amps do. So, if you have one of these amps, and an RF spurious HT, like those early Beofangs, this would be an ideal amp to use on it. Anyway, good INFO, I believe. 

75
https://archive.org/details/ye-poor-mans-am-carrier-current-coupler-10-5-2024-experimental       Experimental Medium Wave Band Carrier-Current Coupling Unit for Broadcasting via FCC Part 15 Rules permissibly. I have had very limited time to work on this project, therefore, I am leaving it to the Open-Source DIY'ers out there to go ahead and run with this. There is no physical, electrical, connection from a transmitter's RF Output to the power lines, but it is all LC, (Inductively & Capacitively.), done to couple Radio Frequency signal to the AC power line. This will help alleviate the hazards and fear of electrical AC shock. That said, care and safety still needs to be observed. Power levels tested were as low as 2 milliwatts. VSWR stayed below 1.5:1 from 530kHz to 1710kHz. However, best coupling effectiveness seemed to be around 1200kHz. One possible problem with this method of coupling is that there is little, to no, Harmonic Suppression. Therefore, it is suggested to use a well filtered transmitter with this method of Experimental Coupling. Components are all listed on the crudely drawn schematic, and should be readily available. Try this and permissibly broadcast around your neighborhood, or just up and down the street. Ranges will very with power lines locations. You may get a few hundred feet, or even a few thousand. Go to it, and good luck!
BTW, while you are there, on Archive, check out the whole page for schematics, interviews, construction projects, manuals, etc., download and use. https://archive.org/details/@thadood   That page is growing, when I have time to add to it.

Pages: 1 2 3 4 [5] 6 7 8 9 10 11 12 13 ... 42
HFUnderground Mug
HFUnderground Mug
by MitchellTimeDesigns