- I’m calling CQ for a good graphic artist who might design an appropriate logo for ZedNet. Maybe something with… lightning bolts against ones and zeros. I dunno. I’m not creative that way.
- Regarding ZedNet and DMR operation, I refer to you THIS.
- I created a page for the List of YOUR callsigns. HERE Chime in or drop me a note if your call doesn’t appear in the list.
Today I went to a weekly gathering of local hams at a bar/restaurant just up the block from the National Museum of Mustard. Yes, really.
One of the members of the assembly, also my local Elmer, brought a little gizmo.
No, this is not a counteragency to UNCLE.
This is mode of communication that uses very weak signals to create propagation reports. Weak Signal Propagation Reporter.
The idea is this. The gizmo intermittently transmits a very weak signal, about 200 mW that includes location, call sign, etc. Receivers around the world participating in WSPR, which detect and read the signal, some 30 dB below the noise line, then report the contact with information about signal strength etc. to a central network which can be accessed on the internet. Thus, you are able to look up your call sign and see how your antenna is functioning, learn about propagation, etc. The gizmo, below, is just a transmitter. It runs off a little powerbank, such that you might haul around to give your phone a little juice during the day. The Elmer just put that and this into a ziplock to protect it from the elements and let it do it’s thing.
It is, in effect, a beacon.
This is nifty technology, developed by K1JT, a Noble Prize winner in Physics, the guy who also developed FT8. It is highly dependent on the use of a very accurate clock, because part of the way that signals are detected and read require a high degree of synchronization.
Of course some people’s minds immediately go to clandestine, super-secret communications connecting various shady people doing who knows what. But, in the meantime, this is very spiffy.
In the picture below, you do NOT see a WSPR device, though they can indeed by constructed from a Raspberry-Pi. This is my little hotspot for ZedNet (DMR), in the window of my Roman apartment last week.
I wanted to see how from what distance I could reach it and communicate with my little handheld transceiver.
As it turns out, given that streets are narrow and wall of buildings are super thick in Rome, I was able to get quite a distance before I lost the hotspot using the Hi power setting. On an amusing note, when I emerged from a narrow way into a wider spot where cars were parked, when I keyed to TX, all the car alarms nearby went off. So much for stealth!
Meanwhile, I used the ZedNet quite a bit from Rome. Hey you hams! If you get into DMR, contact ZedNet! I also used it from GITMO. Very cool.
In any event, today I made contact with stations operation on a Special Event Day. It is Museum Ship Weekend. Today I contacted, inter alia, USS Intrepid, Mew Jersey, and Wisconsin. I visited Wisconsin the last time I was in Norfolk. HERE It is one of the amazing WWII battleships that is still able to be brought back into service.
I was told by N4WIS, operating on USS Wisconsin, that on 30m they are using the ship’s original equipment! I think around 1.144. On 20m, they have a wire sloping down to the guns. From the site: ” Our station is located on the 03 level aft of the bridge with 2 transceivers. One antenna is a ships 35 foot whip on the port side aft and the other is a Carolina Windom 80 from the yard arm forward to the top of 16″ gun turret #2.”
BB-64’s main battery had nine 16 inch (406 mm) guns, which could hurl 2,700 lb (1,200 kg) around 24 miles (39 km). As a backup she had twenty 5 inch (127 mm) guns in ten turrets which could hit targets 9 miles (14 km) away.
Not exactly WSPR!