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“Getting the Message Through: A Branch History of the U.S. Army Signal Corps” by Rebecca Robbins Raines
CENTER OF MILITARY HISTORY, UNITED STATES ARMY, WASHINGTON, D.C., 1996 (pgs 242-244)

During 1940 President Roosevelt had transferred the Pacific Fleet from bases on the West Coast of the United States to Pearl Harbor on the Hawaiian island of Oahu, hoping that its presence might act as a deterrent upon Japanese ambitions. Yet the move also made the fleet more vulnerable. Despite Oahu’s strategic importance, the air warning system on the island had not become fully operational by December 1941. The Signal Corps had provided SCR-270 and 271 radar sets earlier in the year, but the construction of fixed sites had been delayed, and radar protection was limited to six mobile stations operating on a part-time basis to test the equipment and train the crews. Though aware of the dangers of war, the Army and Navy commanders on Oahu, Lt. Gen. Walter C. Short and Admiral Husband E. Kimmel, did not anticipate that Pearl Harbor would be the target; a Japanese strike against American bases in the Philippines appeared more probable. In Hawaii, sabotage and subversive acts by Japanese inhabitants seemed to pose more immediate threats, and precautions were taken. The Japanese-American population of Hawaii proved, however, to be overwhelmingly loyal to the United States.

Because the Signal Corps’ plans to modernize its strategic communications during the previous decade had been stymied, the Army had only a limited ability to communicate with the garrison in Hawaii. In 1930 the Corps had moved WAR’s transmitter to Fort Myer, Virginia, and had constructed a building to house its new, high-frequency equipment. Four years later it added a new diamond antenna, which enabled faster transmission. But in 1939, when the Corps wished to further expand its facilities at Fort Myer to include a rhombic antenna for point-to-point communication with Seattle, it ran into difficulty. The post commander, Col. George S. Patton, Jr., objected to the Signal Corps’ plans. The new antenna would encroach upon the turf he used as a polo field and the radio towers would obstruct the view. Patton held his ground and prevented the Signal Corps from installing the new equipment. At the same time, the Navy was about to abandon its Arlington radio station located adjacent to Fort Myer and offered it to the Army. Patton, wishing instead to use the Navy’s buildings to house his enlisted personnel, opposed the station’s transfer. As a result of the controversy, the Navy withdrew its offer and the Signal Corps lost the opportunity to improve its facilities.

Though a seemingly minor bureaucratic battle, the situation had serious con­sequences two years later. Early in the afternoon of 6 December 1941, the Signal Intelligence Service began receiving a long dispatch in fourteen parts from Tokyo addressed to the Japanese embassy in Washington. The Japanese deliberately delayed sending the final portion of the message until the next day, in which they announced that the Japanese government would sever diplomatic relations with the United States effective at one o’clock that afternoon. At that hour, it would be early morning in Pearl Harbor.

Upon receiving the decoded message on the morning of 7 December, Chief of Staff Marshall recognized its importance. Although he could have called Short directly, Marshall did not do so because the scrambler telephone was not considered secure. Instead, he decided to send a written message through the War Department Message Center. Unfortunately, the center’s radio encountered heavy static and could not get through to Honolulu. Expanded facilities at Fort Myer could perhaps have eliminated this problem. The signal officer on duty, Lt. Col. Edward F French, therefore sent the message via commercial telegraph to San Francisco, where it was relayed by radio to the RCA office in Honolulu. That office had installed a teletype connection with Fort Shafter, but the teletypewriter was not yet functional. An RCA messenger was carrying the news to Fort Shafter by motorcycle when Japanese bombs began falling; a huge traffic jam developed because of the attack, and General Short did not receive the message until that afternoon.

Can I mention the ‘C’ word?

I mean contests. I refuse to call it sport radio as to me a sport involves sweating and physical discomfort. Sitting in front of a radio shouldn’t be uncomfortable. If it is you may need a new chair.Yes, there’s an element of competition, but that’s also true for growing the largest marrow. Anyway on to the point of this post.

Today was a first for me, the RSGB 144Mhz AFS contest was on and I thought I’d give away a few points, so instead of plonking the 5 ele yagi in the loft and leaving it in one place I put in on the end of my aluminium telescopic (wobble-o-matic) mast. The results were never going to be exceptional given I seem to live underground as far as rf is concerned but it was nice to give away a few points to those with higher real estate.

I’ve decided to give the UKAC contest a go as a ‘proper’ operator from a nearby hill and will use that kit with the FT-817 because I don’t have batteries for the IC-7000. If anyone is concerned if I’ve caught the contesting bug, I don’t think so, as today had most of the daylight spent at a local theatre and ‘A Muppet Christmas carol’. 200 kids, mince pies, snot and Marmite and someone dressed up as what looked like the Easter bunny with stick on horns. Both our kids were fairly sure it was Rudolph so that’s good.

QRB was Devon for me today, which was pleasing. All with 50w and a small yagi on the end of a pole. Lets see if I can improve on Tuesday night. Glad to see I’m firmly rooted to the bottom of the table though.

In mid November I sold my Kenwood TS-590 to finance the purchase of an Elecraft KX3 and become a full time QRP operator.  One of the advantages of the KX3 is SDR I/Q output, which can be used to drive a panadapter.  After some fidling around, I have a configuration that works with the popular NaP3 software and thought I would share the highlights in hope of saving you some effort.  This is by no means an exhaustive setup and configuration guide for NaP3, but it should be enough to get you started.  Remember you can click on the images to enlarge them.

For this example I have used the integrated sound card in my PC and have not yet put a ground loop isolator inline which are both opportunities for improvement.

NaP3 Audio In Advanced Tab

We begin by manipulating the input sound card port configuration as shown above.  This will vary somewhat from sound card to sound card, but we want to be sure that we are capturing two channels and that the sampling rate is set at the maximum your card supports, which may take some experimentation and is not necessarily the highest sampling rate shown in the drop down.

NaP3 Setup Tab

Here on the setup tab of the NaP3 configuration, we need to select the sound card input we are using and where we would like NaP3 to output decoded audio.  Once again we have the option to manipulate the sampling rate, which as you can see is 48k for my sound card.  In addition, we need to select “Elecraft K3” for the Rig Type and specify our CAT parameters.  I began this adventure trying to use the “Elecraft KX3” Rig Type, but I found it to not work very well.

NaP3 IF Tab

Here is the “fun” part, at least it was for me until I started banging my head on the desk.  Be sure to set your “Global Offset” to 0 and select “Swap I/Q Channels”.  The “IF Frequency Offsets” is where you will have to spend some time playing.  The method I used was to tune to WWV in CW mode on the KX3 and determine the differential between the frequency displayed on the KX3 and the panadapter display.  I then set the offset to compensate.  To configure the offset for USB and LSB modes, I reduced the offset by the amount equal to my CW sidetone.  This should get you pretty close, but may still require a little tweaking.  Feel free to try my numbers, but I am unsure if they are valid from KX3 to KX3.

If you determine some other method to set the offsets, please let me know as this is the most time consuming portion of the configuration.

NaP3 Spanadapter View

When it is all over, this is similar to what you will end up with, a nice broad view of the spectrum centered on your rigs current frequency!

The source of all my Faros problems…..The netbook itself. I hadn’t actually checked the obvious and that was what it was. The noise generated by the netbook was stopping it from finding signals in all the noise. Hence the 100% QSB. When I disconnected and unplugged everything the noise level dropped massively and that was the end of the problem.

Trouble is I sort of need that to run the program. Oh well, I suppose I can try and run it under wine with Linux and put it on the RPI as that makes little or no noise. I feel some hours being used up ahead!

Its probably not news to many people but whilst I was thinking about a suitable site for the UKAC 144Mhz contest next Tuesday (4th December) I remembered about a coverage prediction programme called Radio Mobile.

Now seeing as things on the internet are steadily replacing things on the desktop I had a go with comparing sites with the model outputs. As a contest novice I am entering in ‘in the spirit of’ contesting. Any site needed to be quite close to home and easily accessed / operated from.

Radio mobile confirmed what you’d expect, the site closest to home that I can get to with the car isn’t the best but its a whole load better that operating from the house. So armed with the knowledge that I’ll get some contacts at least I’ll take the plunge and aim not to be at the bottom of the pile.

The key kit will be

1. A warm coat (its 20.00UTC – 22.00 UTC) – So it’ll be chilly

2. FT817 and extra power supply – Seeing as it runs out of puff within a few minutes

3. Sotabeams 3 element yagi and fishing pole

4. A flask of tea and chocolate hobnobs

The output from a 4w Tx at the Sandwith site is below. More than enough to get a couple of contacts I hope.

We’ll have to see how I get on next week, but if you’re in earshot listen out for the weedy signal from Cumbria (rather than the stronger on from G4VFL, who has nabbed the Corney Fell site – perhaps I should tramp up Scafell Pike to out do him on height!)

At the back end of last week I set Faros off and running to listen into the various NCDXF beacons.

All is not well

The set up of rig, Signalink, sound card (either as a usb or internal) is inconsistent at best and not hearing anything at all at worst. After a few days of twiddling and mucking about I am at a loss. I’ve never really got the thing going with my ft817 and frankly don’t want to spend a whole heap of time trying to sort it out. Perhaps I’ll go back to it once I’ve had a chance to think about it a bit more.

Here’s what’s stumping me:

Computer – More powerful than the one it used to run off 24/. Both internal and usb sound cards have failed to get any signals. in fact the usb sound card made the software act very oddly. Audio in directly from the rig…no difference. Adjusting the volume makes no observable difference.

Rig – CAT OK, timing OK, audio out OK

The software is reporting 100% QSB which I don’t recall from the last set up so I can only surmise that it doesn’t like the two options for the sound card. Time to take a break from it.

The NCDXF beacon network may not be as popular now that WSPR has hit the mainstream but I think it still has a purpose.

For me, the benefit of programmes like Faros gives life to a receiver that wouldn’t otherwise be used. Yes, you can do the same with WSPR but because it’s a more robust system means that just because my pc can hear a station. Doesn’t mean I can work them.

Beacons,on the other hand , give you a reason to listen out. For example, if I can’t hear the Northern Ireland 2m beacon, GB3NGI on 144.482Mhz then chances are I will not be successful putting out a CQ call and expecting to get some DX (DX for me is probably a lot less in mileage terms than you might think at my QTH).

So I’ve resurrected the NCDXF beacon monitor and the results are on the Beacon pages. I hope they are still useful. Time will tell but it looks like the soundcard / rig combo isn’t working too well as its reporting 100% QSB and nowhere near as many spots as I would expect it to. I remember the software being quite precise about the signal input and I spent many hours waiting then adjusting.