22 June 2022

Message Center Clocks

I love clocks and watches, and I've written about this in the past. I also love to research and read about the history of radio, particularly radio operations involving two way communications (as opposed to broadcast radio, which is one-way only). It's clear that radio and time are inseparable. Just about everything in radio revolves around time. Our formal nets start and end at defined times. Much of our software like WSJTX and JS8CALL is tightly time dependent. Modern military and, increasingly, commercial transceivers are dependent on accurate time signals to synchronize things like frequency hopping, automatic link establishment, and automated digital messaging operations. Time is everywhere in radio. Has been since Guglielmo Marconi first thought about commercializing his 'invention' back around 1900.

My earlier post was about radio room clocks, particularly those that call out the mandatory quiet periods at 15 and 45 minutes past the hour. These clocks were designed specifically for maritime radio room use - a reminder to the operator to cease transmission for a 3-minute period and just listen on 500 kHz for any distress calls.

But there was another use for clocks in conjunction with radios, a use that was somewhat more utilitarian but just as important - in military message centers.

First, let's define what a message center is. A message center is nothing more than one or more radios dedicated to transmitting and receiving message traffic. If you were in the military for any length of time, particularly if you worked a job that involved coordinating activities at a brigade or higher headquarters, you'll have heard the terms 'comms (communications) center' and 'message center'. A comms center is an over-arching communications environment that handles both direct voice communications and message traffic, while a message center is dedicated to handling just digital or voice message traffic - orders, reports, etc. When a commander wants to talk by voice to one of his subordinate commanders he goes to a comms center. When he needs to send a report to his higher headquarters he goes to a message center. The difference between the two was often very fuzzy, particularly at the lower battalion and company levels, where one or two radios were handling ALL voice communications and message traffic duties. But at higher command levels, with steadily increasing volumes of message traffic, a dedicated message center was usually required. 

And, of course, message centers needed clocks. Everything was coordinated by time. Radio message traffic needed to be time-stamped and logged with the time received or sent. Operators needed to know when to switch frequencies to handle message traffic on different nets. They needed to time-track when physical messages (paper copies) were received or handed off. Basically, everything in a message center revolved around time.

It was during WWII that the concept of a purpose-built message center clock took hold. There may be earlier designs, but if there are I have not seen them. My my guess is that prior to the WWII era militaries just used whatever cased clocks they could procure. But starting with the run-up to WWII (which, remember, started in Europe in 1938 - a full 3 years before the the Japanese bombed Pearl Harbor), a few militaries like the US and Germany started specifying designs for message center clocks. Let's start with the US. The Army took the smart and easy path, and asked manufacturers like Chelsea, Hamilton, and Lowe to make a variation of the maritime 'deck clocks' they had been making for years. The first clocks were brass cased, later switched to a phenolic (Bakelite?) housing to conserve a strategic metal that was in short supply. The movements in these clocks were fairly rugged, simple to service, and were already in volume production. All the US Army had to do to make them 'army' was to have the words 'Clock Message Center M1 (or M2)' stenciled on the face. The M1 models had 4" faces, the M2 models had 6" faces, and most seem to have come with a secondary 'zulu time' hour hand. The Army had them mounted in a clever flip-open wooden box, which made them easy to transport and set up.

Clock Message Center M1 (4" face) in a brass case. Brass was a strategic metal during
WWII and clock cases were quickly switched to a phenolic (Bakelite?) case

The far more common M2 message center clock (6" face) in a phenolic housing. 
The red hand is the 'zulu' or second time zone hand

These clocks were a commodity item, produced in the thousands. If they appear in period photos at all it's because the photographer was taking a picture of something else and the clock just happened to be in the shot. Here's one of the best known (and clearest) photos of a message center clock in use. This photo is interesting because it looks like the radio is being used in an early M2 or M3 Scout Car. Note the telegraph key strapped to the operator's leg, and the home made speaker box. I'd guess that this picture was taken either pre-war, or immediately after the US entered WWII. This is a great example of what a 'message center' looked like in small units during the war - a single radio, a single operator, a clipboard with some standard message forms, and a clock.

Some have asked, why not rely on wrist watches? A good question. We have to remember that prior to WWII a good quality wrist watch was a fairly expensive consumer item. Not everyone owned one. This was almost half a century before the arrival of cheap but accurate quartz watches. In the 1930's and 40's all watches were hand assembled mechanical units that could cost a working man's weekly wage, or more. Plus, the US military can not compel soldiers to use their personal property for official purposes - which means they can't compel you to buy and use a wrist watch as part of your Army job. If your job requires a watch, they'll issue you one. However, it's cheaper to provide a single clock that's available for all to reference than hand out a bunch of wrist watches. Then there's the issue of time synchronization. All activity in a message center had to be referenced to a single time source. If everyone is using their own wrist watches, and each watch is off a minute or two in either direction (very common with mechanical watches) then how are you sure that Message A arrived before Message B? In wartime this matters, a lot.

The German Army took a similar approach. Called a 'funkuhren' (radio operator clock), it was a standardized clock specifically designed to be used in message and communications centers. However, their clocks were a bit different - they appear to be large pocket watch movements in a modified case with a larger mainspring, giving an 8-day runtime. The whole thing is mounted in a wooden case, and the movement can swing out for winding via a  knurled knob or stem on the rear. Actually a pretty good arrangement. since it doesn't require a winding key like the American clocks do. 

Evidently this design was so good that the Germans kept it in production after the war for issue to the new Bundeswehr communications units. I can't help but wonder if there's a warehouse full of these things somewhere in Germany, in unissued condition, waiting to be dumped out onto the collector market at reasonable prices. One can only hope...

Note the 'funkuhren' on the table in the lower left. This German soldier is running a Hellschreiber unit.
 You can still run Hellschreiber using digital mode software like Fldigi, and it's a lot of fun!

Note the 'funkuhren' on the table between the two radios

So we've looked at US and German message center clocks from WWII. What about the British, French, Japanese, Russians, Canadians, etc? Honestly, I don't know. I've never seen any write-ups or on-line discussions of message center or radio room clocks in use by other countries involved in the war. I can only guess each country had some sort of standardized timepiece they adopted.

Now let's push forward to today. As a MARS and SHARES member I run a small message center. So I need a message center clock, right? OK, it's just for looks and tradition, but to me it's important. I'm always trying to connect the past to the present, so we don't forget.

Chelsea, the US company that made the majority of message center clocks in WWII, is still making pretty good reproductions. Not exact replicas, but considering the cost of a good working Army surplus M1 or M2 clock, they are good enough. In a nod to modern times and cost, these clocks use battery powered quartz movements. They also still use the same phenolic cases that Chelsea started using in WWII, but now they are made of a more up-to-date glass reinforced plastic. Overall they are pretty good clocks, and have a place in even the most modern of ham radio shacks.

A modern (quartz) interpretation of the classic US Navy deck clock, which was adopted
by the US Army as 'Clock Message Center M2'

A modern Chelsea 'radio room' clock. I like this one for it's accurate quartz movement and 'zulu'
or second time zone hand

But I have to think that the Germans did a better job of it, particularly for smaller setups. The Chelsea M2-style clocks are big. Six inches may not sound like a lot, but when the clock is sitting only a few feet from your face, it's a bit imposing. The smaller 4" M1 message center clocks would be a better option, but nobody makes a replica, and originals are very hard to find. The smaller German 'funkuhren' clocks seem like they were better suited to small setups. Sadly, nobody makes a 'funkuhren' replica, and good working examples go for silly high prices. But the idea that a large(er) pocket watch format can serve as an ersatz message center clock has me intrigued. 

My grandfather's Illinois Bunn Special pocket watch in front of a 6" Chelsea radio room clock

And I think I've spied my solution, courtesy of Seiko. It's the Seiko SNE370 wrist watch. It's not as large as a pocket watch, but at 43mm it's it's plenty big enough. It's got a clean, uncluttered face with a 24 hour inner ring, and it's got an accurate quartz movement. I can do without the day/date readout, and I'd love a second hour hand (a 'zulu' hand or, as it's called in the watch world, a GMT hand), but you can't have everything. One problem though... it's out of production. Aaarrrgggghhhh! I can't catch a break.

Seiko SNE370 Solar.
Do me a favor - keep your eye out for one!

W8BYH out

18 June 2022

Decisions, Decisons

The XYL and I are beginning preparations for a week long camping trip later this summer. Of course radio will be part of the adventure. The question is, which radio(s)? If I look at the goals I have for this trip (beyond campsite setup and tear-down, meal prep, entertaining the XYL, walking the dogs, entertaining the dogs, feeding the dogs, general camper maintenance, shopping, talking with camper neighbors, sightseeing, etc, - those of you who camp know what's involved), the things I want to do with radio include:

  • chasing DX
  • POTA activations
  • Winlink
  • MARS
  • testing & playing with ALE (Ion2G)
Of course the IC-705 is in the mix. It's become my default camping radio. It can easily handle the DX, POTA, Winlink and JS8CALL duties, but at a low TX level (max 10 watts). 

But for MARS and ALE I'll need a different rig. I've got a number of MARS modded radios - IC-7300, Yaesu FT-991A, IC-7100, IC-7200, even my Elecraft KX2(!), but only two are suitable for ALE operations - the IC-7300 and the IC-7200. Both of these radios bypass the band relays when scanning in 'split' mode. This means as the radio scans from band-to-band while running ALE you don't hear the 'clack-clack-clack' of the mechanical band filters switching in and out. The 7300 does this out-of-the-box, and my 7200 has the 'quiet scan' mod which achieves the same result. 

IC-7300. The all-around champ in my radio stable

IC-7200. Not as capable as the 7300, but a good bit more rugged

Almost as important as the radio is the antenna selection. The campsite is a bit cramped, with 'neighbors' close-by. I won't have space to string a 120' end-fed, or even an 80' dipole. I always have a Chameleon end-fed EMCOMM II with me, just in case, but for high power HF I'm likely going go have to rely on a vertical. Problem is, most modern campsites are awash in RF hash generated by any number of consumer devices that campers bring along, from LED light strings to portable generators. A vertical is precisely the wrong type of antenna to use in that environment - they attract electronic noise and hash like a magnet attracts iron filings. I have a magnetic loop, which is electronically quiet - mainly because it's so narrow banded - but it's only good up to 25 watts on sideband, even less on digital.
Vertical HF - occupies relatively little real estate, but attracts interfering RF
like a magnet

Mag loop antenna - quiet and effective, but can only handle 25 watts

I guess I've got some testing and planning ahead of me. Oh dear, how will I manage? 

W8BYH out

04 June 2022

Situational Awareness Map Updates (June 2022)

 As many of my readers know, I publish and maintain the Georgia ARES Situational Awareness Map. This map is a project that goes all the way back to 2016, when Georgia ARES was looking to improve the quality of repeater data in the state. At first the map was just a front-end to a project called the Georgia ARES Repeater Database Initiative. The repeater database initiative was seen as a way to get repeater owners to submit and update their own data, thereby improving the overall accuracy and reliability of repeater information. The map was created simply to show repeater distribution across Georgia, but was very quickly added to and improved. By 2019 the map had moved far beyond its original purpose, and had morphed into a situation awareness tool.

As with any web-based product or site, changes happen with regularity. New data layers become available, old data layers are pulled off-line. The development platform itself changes over time; the technology base that the map is built on undergoes revisions and updates. New capabilities are added, performance improvements are introduced and security vulnerabilities are fixed. I'm lucky in that the technology platform I use - ESRI's ArcGIS Online - is updated quarterly and they are always bringing new capabilities and features to the web mapping environment. The Situational Awareness Map has undergone at least three major changes in five years, as ESRI has updated the underlying platform. It's the latest change that I'll be discussing here.

The map has been moved to a new environment called Experience Builder. Experience Builder is a highly configurable web mapping environment that gives the developer a wide variety of tools and options to pick from, without having to write any code. While I could have hung on to the older development environment for a while longer (it will be decremented over time), there is capability in Experience Builder that I've been waiting years for ESRI to introduce. So, over to Experience Builder we go!

I have also decided to close down the associated Georgia ARES Repeater Database initiative. It's had a good run, but participation has fallen off and it's no longer worth the effort to keep it going. For repeater data I now rely on Repeaterbook.com. The owner of Repeaterbook.com, Garrett Dow, KD6KPC, has been extremely gracious in giving me permission to include his repeater data in the map at no charge. 

I'm also broadening the focus of the map. Until this update the Situational Awareness Map was entirely Georgia-focused; it was as though Georgia was an island unto itself. However, we are often directly influenced by what happens in other states, particularly when it comes to weather. Some ARES ECs, particularly those that serve counties that border other states, have asked that I extend coverage into these neighbor states. That process was started with this update, and I now make county and repeater data available for Alabama, Florida, Tennessee, North Carolina and South Carolina.

The map also takes advantage of a new feature I call 'layer groups'. In the old map, there was no way to group related data layers (say, 70 cm, 1.5 meter and 2 meter repeaters) under a single heading. This resulted in an overly long and complex data layer listing that was difficult to navigate. The new layer grouping feature makes finding data layer much easier, and provides a cleaner, simpler layout. 

Expandable and collapsible layer groups
 makes navigating data layers much easier

Other enhanced features or new data in the map includes:

  • The ability to generate elevation profiles - line of sight between two points - directly in the Situational Awareness Map. The capability is available in the function 'widget' bar at the bottom of the map (the line of blue circles). In the past this capability was only available in a separate application, but I've been able to incorporate the feature directly into the map
  • Georgia repeater coverage heat mapping (under the Repeater Planning Coverage layer group). This layer provides repeater density-based heat mapping to help evaluate repeater coverage 
  • Under the Situational Awareness Infrastructure layer group, I've added Georgia Dams (Safe Dam Program) managed by GDOT, and I've re-added Beach Webcams. The camera layer is what I'll call 'fickle' - these are cameras installed and maintained by commercial activities like resorts and hotels. Camera feed availability can be spotty, particularly during hurricanes or coastal storms. If the camera feed is up and operating, great. If not, well...
  • Under the Transportation layer group, I've added GDOT 511 Events - a point layer of major traffic issues, mainly related to long-term construction activities. I've also brought in a more up-to-date GDOT traffic camera feed - GDOT 511 Cameras
  • Under the Hurricane / Tropical Storm Response & Management layer group, I've added the national data layers for the NOAA Storm Surge (SLOSH) Data. SLOSH stands for Sea, Lake, and Overland Surges from hurricanes and storms. These layers help visualize coastal areas that will be inundated in each of the five hurricane categories 
  • Under the Grids layer, I've added the Georgia State Patrol GSP Aviation SAR Grid. This grid divides the state up into roughly 16 x 19 mile grid squares used to coordinate aerial search & rescue activities
That's it for the major updates. As I mentioned earlier, this Georgia map will be taking on a larger regional focus over time. Recently I was contacted by the Maryland Section Emergency Coordinator to see if the Georgia Situational Awareness Map functionality could be extended to the mid-Atlantic states. The project is in the works, and has the support and involvement of ARES leadership from Maryland, Delaware, DC, Pennsylvania, New Jersey, Virginia and West Virginia.

The point here is that if you are an ARES or EMCOMM leader in one of Georgia's neighboring states - Alabama, Florida, Tennessee, North or South Carolina, now would be an opportune time to ask about a situational awareness map specific to your state. Just drop me a line at w8byh@arrl.net.

W8BYH out