Bild: Ein Eichelhäher hat sich ein Erdnuss geschnappt.
Ihr habet es sicher in der Zeitung gelesen oder im Radio gehört. Nachdem massenweise Pager explodiert sind, explodierten einen Tag später nun viele Handfunkgeräte im Libanon.
Dazu einige Details, die vielleicht nicht in eurer Zeitung stehen. Es handelte sich bei den Geräten um ICOM IC-V82. Dass diese Geräte von Icom stammen ist eher unwahrscheinlich. Die Fabrikation des IC-V82 wurde im Oktober 2014 eingestellt.
Doch von ICOM, wie auch von anderen Markengeräten, gibt es Kopien aus China. Ein Beispiel dafür ist der FT-7900R aus China. Das Gerät ist ein 2m/70cm FM-Mobiltransceiver mit 50W Leistung. Er ist auf Ebay und anderswo für ca. 170 $ zu haben. Ein Schnäppchen auf den ersten Blick.
Doch der FT-7900R wird schon lange nicht mehr von Yaesu, Japan fabriziert. Die Geräte sind Kopien aus China. Ob sie die ursprünglichen Spezifikationen des Originals einhalten, ist fraglich. Auf jeden Fall sind es Kopien der amerikanischen Version (R) und nicht etwa FT-7900E. Hände weg, auch wenn sie kaum explodieren dürften.
Icom IC-V82 handheld transceivers designed for amateur radio use have been identified as the latest device to deliver deadly explosions targeting members of Hezbollah. The identification of Icom radios follows an initial attack on members of Hezbollah in which pager devices were used to deliver deadly explosions.
Icom is investigating the reports of its radios being used in these attacks while Icom sales reps believe the radios identified are knock-offs. Icom is expected to release its findings on its website. The IC-V82 was discontinued in 2014.
The WinLink training will start on September 23 at 8:00 PM CT. You will need to be prepared prior to the start of training.
To be prepared you will need the following setup
o A computer with WinLink installed (no radio required) and dual monitors. One monitor for the A/V conference and the second for your WinLink session. OR o A computer with WinLink Installed (no radio required) and either a second computer/laptop or tablet. The first computer will run WinLink while the second computer/laptop/tablet will be used for the A/V conference.
o Internet access on both devices.
The WinLink training will take 3 to 4 one hour sessions.
I will send a Winlink message to everyone by 6:30 PM on the day of the training with the A/V conference link.
If you know other that want to attend have them send an email to WG5GK@winlink.org. (Don’t forget the //WL2K in the subject line) I have 5 slots available.
Beginning January 1st, Radio Society of Great Britain (RSGB) will no longer offer paper based amateur radio licensing exams except for special educational needs. Already, 97% of all amateur license exams are conducted online remotely or within a club space. Additional costs and effort around paper based exams were cited as reasons to move to an all digital format. Key dates:
Paper exams continue until December 13
November 29 is the last day to book a paper exam
Paper exams will no longer be available beginning January 1
Today I received my copy of the RSGB RadCom. One large UK dealer has most of the advertising space. I have no idea what this must cost, but it must be a lot. If this major dealer decided to stop advertising, or advertised far less, it would have a major impact on the RSGB and the remaining UK radio magazine available on newsstands.
Without this one dealer, I suspect RadCom would have to shrink in size and the one remaining magazine radio amateurs could buy in newsagents would enter terminal decline.
We have a very busy history society in our village. Tonight was the first meeting of the season and was on Fen Skating which is in decline as a result of global warming.
On Wednesday the Nickel Belt Net celebrates its 6th Anniversary on the 40m band. If the band conditions allow check in with them on Wednesday afternoon and give them a hearty “Congrats” for a job well done.
1494 2030 Coast FM via relay. SINPO 34433. 1629 2020 Radio Bluebird. SINPO 44433. 1638 2013 Radio Eigen Risico. SINPO 34433. 1665 2007 Radio Wilskracht. SINPO 44433. 5020 1650 Radio JVG. SINPO 34433. 5030 2000 Deltracks. SINPO 44433. 5880 2036 Radio Rock Revolution. SINPO 34433. 6205 1823 Laser Hot Hits. SINPO 54444. 6290 1725 Radio Ronalisa (pres). SINPO 34333. Relay of Dutch MW station 6300 1809 Radio Boomerang. SINPO 54444. 6925 1730 "Radio 6925". SINPO 54444. No real ID but in pirate chat as this. Later on 6880
FastRadioBurst 23 here with news of what the Imaginary Stations crew are up to. This Sunday coming on 22nd September 2024 there’s another episode of Skybird Radio International via the services of Shortwave Gold. The show which features an across the board selection from around this musical globe of ours will be broadcast at 0900/1300 […]
Dr. James Breakall, WA3FET, Receives Major Award from the RCA
Wednesday, September 18, 2024 - 11:59
Wednesday, September 18, 2024 - 11:27
Submitted 14 hours 43 min ago by af8a.
Congratulations to long-time HamSCI member Jim Breakall, WA3FET, on receiving the Dr. Ulrich Rohde Award for Innovation in Applied Radio Science and Engineering from the Radio Club of America (RCA).
Established in 2023, this award recognizes significant contributions to innovation in applied radio science and engineering in the wireless industry to inspire future generations of wireless professionals.
'Dr. Jim' received B.S. and M.S. degrees in Electrical Engineering from Penn State University and a Ph.D. in Electrical Engineering and Applied Physics from Case Western Reserve University, Cleveland, Ohio. He has over 50 years of experience in numerical electromagnetics and antennas. He was a Project Engineer at the Lawrence Livermore National Laboratory (LLNL-Livermore, CA), and an Associate Professor at the Naval Postgraduate School (NPGS-Monterey, CA). He is currently a Professor Emeritus of Electrical Engineering at Penn State.
He began his career as a graduate student at the Arecibo Observatory in Puerto Rico, working on antenna analysis and radar probing of the ionosphere. At LLNL, he and his group worked on the development of the Numerical Electromagnetics Code (NEC), the first sophisticated antenna modeling program. Other significant projects that he has worked on were the designs of the HAARP facility in Alaska, both HF facilities at Arecibo, and the Kinstar low profile AM broadcast antenna. Dr. Breakall (electrical) and HamSCI member/supporter Tim Duffy, K3LR, (mechanical) designed the very popular Ham Radio Skyhawk Yagi antenna, and Dr. Breakall is the inventor of the Optimized Wideband Antenna (OWA).
Dr. Breakall is a member of several IEEE societies, Eta Kappa Nu, International Union of Radio Science Commission B, and the IEEE Wave Propagation and Standards Committee. He has been an editor for several journals. He is a frequent speaker at the Dayton Hamvention Antenna Forum.
He received the RCA Sarnoff Citation and is a Life Fellow of IEEE and a RCA Fellow. He serves as an RCA director and as the Co-Chairman and later Chairman of the RCA Technical Symposiums. He also serves on the RCA Scholarship Committee, Education Committee and Awards Committee, and Innovation Council.
I’ve been toying with the idea of putting together a small radio kit based on my (tr)SDX or something similar, so I’ve been looking at small paddles to go with it. Browsing through eBay recently, I came across several listings for the QU-21C paddles. They were inexpensive, so I thought I’d order them and give them a shot.
These paddles are nothing new; they’ve been around for a few years. (I’m definitely no early adopter.) The QU-21C paddles are made in China and mine are marked with the brand name, Magic Rabbit. From other reviews I have seen, there may be other manufacturers. So, the quality and packaging may vary. I paid about $24 USD from a seller (iDrone) that ships from the U.S., but you can find them listed for less than $20, if you don’t mind waiting for a shipment from China.
Opening the package, I found the paddles are even smaller than I expected. The base is approximately .98 inch by .98 inch (25mm x 25mm) and 1 inch (26mm) tall. The overall length, including the paddles, is 1.9 inches (48.5mm). On my kitchen scale, the paddles weighed in at 1.25 ounces (34 grams). The paddles appear to be 3-D printed, but the quality is pretty good. The base of the paddles is magnetic, which is one feature that first drew my attention.
Magic Rabbit QU-21C paddles with the rubber pad attached to the magnet. The pad looks a little ragged around the edges, because I applied it, removed it, and then decided to put it back on. I messed it up a little in the process.
The package I received included:
Paddles with a magnet attached to the bottom
3-ft cable with 3.5mm stereo plugs on each end
Hex wrench for adjusting contact spacing
Two adhesive metal discs
Adhesive rubber pad
Plastic storage case that holds everything
Some of the accessories that came with it. The cable is inside the clear plastic storage box. The adhesive discs can be applied anywhere, so you can use the attach the paddles magnetically.
My first impression was that the contact spacing seemed a little wider than I like. I used the supplied hex wrench and adjusted the spacing until the contacts were completely closed. Then, I backed off a little.
I prefer a light spring tension on my paddles, but the spring in these paddles seems stiffer than I’m used to. Unfortunately, there’s no adjustment for that. So, I’ll just have to get used to using a little more force than my other paddles.
I’m not sold on the magnetic base, though. The square magnet is fairly strong, but it’s highly polished. So, the paddles sometimes have a tendency to slide when I’m sending. I applied the rubber pad that comes with it, but that seemed to offer only minimal improvement. For now, I just hold them in one hand while sending with the other.
I’ve actually thought about trying to remove the magnet altogether, since it appears to be glued on. At least, it wouldn’t be attracting every ferrous object that comes near it. But, for now, I’m just thinking about it.
The QU-21C paddles during a recent activation, along with my trusty Palm Mini paddles.
I had a chance to use the QU-21C paddles on a recent park activation. It didn’t take long to get used to them, and I had no issues with them at all. The paddles keyed reliably, without missing a single dit or dah.
Even with my spring tension and magnet gripes, I’m pretty happy with these paddles. These cheap paddles look like worthy candidates for field use. We’ll see how well they hold up over time.
A Failure To Communicate! Those ominous 4 words have appeared in reports such as the 9/11 Commission Report, or in describing 20M Band Conditions and then extending even to an equipment breakd0wn. In short, these issues are the causal factors of a failure to communicate and not so much inside the communications itself.
The inside the communications factor can be seen in the current political environment where it is suggested that immigrants are eating your pets. It is clear the pet eating comments are to grab the headlines and not so much to identify any problem. The solution to that is November 5th.
I also believe those 4 words were used in a Paul Newman movie ~ Cool Hand Luke.
There is yet another aspect in the assumptions we individually make and then ask for something based on a not so clear assumed condition. I received another email last week that simply said send me the code. I wrote back that unless the person identified the specific project I was at a loss as to what to send as it was a failure to communicate. I have not heard back.
Without making an issue, the several requests for send me the unidentified code came from offshore where English is not the primary language. So that may be a factor but that is not an excuse!
The new phrase might be: If You Want Stuff You Have To Know Stuff. The knowing may be as simple as identifying specifically what you want.
Rated #1 on Sherwood Engineering's list
This raises a question (back on to the Techie Stuff). The question of the day involves gain distribution in a homebrew receiver and where should the gain stages be applied. This borders on how big is big?
But as we well know everyone wants a specific number if only to argue -- that is too big or too small. For the one or two sharp shooters in the blog readers set, your ears should perk up as you ready an argumentative response.
There are neat terms like MDS (minimum discernable signal) where you can quantify that a particular topology can copy a weak signal with the weakest identified as MDS.
Too much gain at certain parts of the signal train can cause a lot of noise to be amplified and carried along with the signal. This is especially true in front end RF Amplifier stages. Several commercial designs simply have no RF amplifier stages. This tends to work well below 20M but when you get beyond 17M -- the receiver almost sounds like it is on life support. No Noise BUT No Signals.
So, by picking a reasonable level of RF amplification walks the thin line of boosting the incoming signal without overly boosting the noise. A gain of say 5 to 10dB for the RF Amp would be a starting place.
But external noise is not the only noise as there is noise internally generated within the receiver itself. This drives what you use and how you use it. Running stages Class A would likely result in a different outcome than from those running in other classes of operation.
Analog Devices has an exhaustive paper on noise in a receiver and can be seen here.
Intermediate stage gain must consider that you want to assure you are not hitting the Crystal Filter with a sledgehammer. W7ZOI has often used a Pad after the post mixer amplifier so you are not really banging the crystal filter with signal. It also helps if you limit the bandwidth of the signals being applied to the filter especially those coming from the Balanced Modulator in a transmitter configuration.
A chance to make up for signal deficit lies with the audio amp stage. Not any old stage like a LM386, but a well-designed stage that delivers a significant amount of stage gain without a lot of noise in the side car is the goal. A homebrew audio amp using multiple gain stages is certainly a choice.
So, what is a number for overall stage gain? Such a number is a trap unless you also consider a clean sound coming out of the speaker. To hedge my answer the overall stage gain should be that required to copy weak signals while minimizing internal and external noise at the band of operation. Old wives' tales often suggested 100dB.
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