Archive for the ‘ham’ Category
MGM 1939 film: Radio Hams / More than a Hobby
“Radio Hams” do more than play with their machines. They are also invaluable in relaying vital information during times of tragedy and disaster.
Here is a mildly entertaining look at radio hams, those amateurs sending and receiving coded messages during the late thirties when films first dealt with the subject of “radio hams.” In this case, the ham operators manage to be helpful during situations of stress, using their abilities with code to help someone in distress and to seek aid for pilots flying a missing plane.
The humorous ending has the family gathered around the radio listening to someone speaking Chinese while the narrator tells us how impressed the family was to be hearing someone across the world on their radio set.
http://www.youtube.com/watch?v=bZi7LiPNMt8
This little vintage film, a rather more serious film than many of Pete Smith’s other presentations, takes a look at how ham radios can become priceless aids during emergencies. The two stories shown, one dealing with sickness, the other with a missing plane, are bookended by a humorous look at a typical three-generation family’s fascination with their ham radio.
Of course, amateur radio, or “ham radio”, is alive and doing very well, in our modern times. Using satellites, moon-bounce communications, repeater networks, as well as shortwave, mediumwave, and longwave telecommunications technology, amateur radio continues to provide emergency services in times of need, from hurricanes, tornadoes, earthquakes, and even during such times as the infamous 9/11 atrocity. But, amateur radio also breeds invention and experimentation, always at the cutting edge of science. It is a hobby worth investigating, having room for a wide-range of interests. Preppers, science lovers, experimenters, and those with a passion to meet people from all over the world by way of radio waves, all together make up the radio hobby of amateur radio.
Clayton Moore, later famous as the Lone Ranger, appears uncredited as a ship radio operator.
Directed by Felix E. Feist
Writing Credits Buddy Adler (screenplay) (as E. Maurice Adler)
Cast (in alphabetical order)
Barbara Bedford – Mrs. Crane (uncredited)
Eleanor Counts – Miss Mulligan, Jimmy’s Sister (uncredited)
Jack Daley – Pa Mulligan (uncredited)
Robert Homans – Lighthouse Keeper (uncredited)
Clayton Moore – Ship Radio Operator (uncredited)
Alonzo Price – Clyde DeVinna (uncredited)
Jason Robards Sr. – Pilot in Distress (uncredited)
Pete Smith – Narrator (voice) (uncredited)
Harry Strang – Man in Montage (uncredited)
Phillip Terry – Co-Pilot (uncredited)
Dorothy Vaughan – Ma Mulligan (uncredited)
Produced by Pete Smith – producer (uncredited)
Music by David Snell (uncredited)
Cinematography by Robert Pittack
Film Editing by Philip W. Anderson (as Philip Anderson)
Music Department Jack Virgil – orchestrator (uncredited)
Other crew Douglas Smith – technical advisor
According to https://archive.org/details/wwIIarchive this film is in the Public Domain.
Creative Commons copyright.
1920 film: How the Telephone Talks (A Silent Film)
This is for you vintage science film buffs: here is a circa 1920 film: How the Telephone Talks (A Silent Film).
This is an educational film from 1920 that explained the “modern” telephone. The concepts are still relevant to today’s modern versions, including the cell phone, which is both radio and telephone.
From Wiki:
A telephone, or phone, is a telecommunications device that permits two or more users to conduct a conversation when they are not in the same vicinity of each other to be heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals suitable for transmission via cables or other transmission media over long distances, and replays such signals simultaneously in audible form to its user. The word telephone has been adapted into the vocabulary of many languages. It is derived from the Greek: τῆλε, tēle, far and φωνή, phōnē, voice, together meaning distant voice.
First patented in 1876 by Alexander Graham Bell and further developed by many others, the telephone was the first device in history that enabled people to talk directly with each other across large distances. Telephones became rapidly indispensable to businesses, government, and households, and are today some of the most widely used small appliances.
The essential elements of a telephone are a microphone (transmitter) to speak into and an earphone (receiver) which reproduces the voice of the distant person. In addition, most telephones contain a ringer which produces a sound to announce an incoming telephone call, and a dial used to enter a telephone number when initiating a call to another telephone. Until approximately the 1970s most telephones used a rotary dial, which was superseded by the modern Touch-Tone push-button dial, first introduced by AT&T in 1963. The receiver and transmitter are usually built into a handset which is held up to the ear and mouth during conversation. The dial may be located either on the handset, or on a base unit to which the handset is connected by a cord containing wires. The transmitter converts the sound waves to electrical signals which are sent through the telephone network to the receiving phone. The receiving telephone converts the signals into audible sound in the receiver, or sometimes a loudspeaker. Telephones are a duplex communications medium, meaning they allow the people on both ends to talk simultaneously.
A landline telephone is connected by a pair of wires to the telephone network, while a mobile phone, such as a cellular phone, is portable and communicates with the telephone network by radio transmissions. A cordless telephone has a portable handset which communicates by radio transmission with the handset base station which is connected by wire to the telephone network.
The telephone network, consisting of a worldwide net of telephone lines, fiber optic cables, microwave transmission, cellular networks, communications satellites, and undersea telephone cables connected by switching centers, allows any telephone in the world to communicate with any other. Each telephone line has an identifying number called its telephone number. To initiate a telephone call the user enters the other telephone’s number into a numeric keypad on the phone.
Although originally designed for simple voice communications, most modern telephones have many additional capabilities. They may be able to record spoken messages, send and receive text messages, take and display photographs or video, play music, and surf the Internet. A current trend is phones that integrate all mobile communication and computing needs; these are called smartphones.
Solar Plasma Filament Eruption – The Sun – November 6,7 2013
The Sun currently is active, with powerful, complex magnetic structures that have formed a healthy number of sunspots. We are seeing a fair number of x-ray flares, which push the 10.7-cm flux higher than we’ve seen in a while.
Sunspots and flares means better propagation in general, especially on the higher frequencies of the shortwave spectrum. While a flare can cause a short period of “blackout” conditions (especially on the lower frequencies) on the sunlit side of the Earth, such activity is part of the positive activity that ionizes the F-region, providing for DX.
Here’s a movie of one such flare and the release of solar plasma, a release known as a coronal mass ejection (CME): At about midnight, UTC, on 6 November 2013, a moderately-strong M-class flare erupted, with a “beautiful” CME: http://g.nw7us.us/18a0QvI
(Source: SOHO/SDO/NASA)
We will see continued flare activity over the weekend, so expect great conditions on the HF bands, with momentary blackouts. Keep up to the minute on space weather at http://SunSpotWatch.com
73 – de NW7US
Propagation Columnist, CQ Communications Magazine, Popular Communications Magazine
http://NW7US.us
Expect Uptick in HF Propagation Even on 10m, This Week
New sunspot region, NOAA Active Sunspot Region Nr. 11890, far left on the solar disc, will produce flares, this week.
The Sun continues to produce sunspots, and this week looks active, too. Expect another uptick of activity on higher HF bands such as 10 meters, as a “new” sunspot region has now rotated into full view. It has a complex magnetic structure, so it could produce moderate and maybe strong x-ray flares. We expect flaring activity to pick up, as a result.
With all of the recent activity, and the continued train of spots, right now, it certainly appears to be a sign of a “second” peak in the cycle. Most cycles exhibit such double peaks. Is this one of them in this current Sunspot Cycle 24?
Enjoy the DX!
73 de NW7US (Your CQ Magazine and Popular Communications Magazine propagation columnist)
Yagi-Uda the III.
No, this is not the name of another royal baby… it’s about my third attempt to build a 2m antenna for my SOTA activations. In my earlier iterations I was unable to strike the balance between size/weight and usability.
What happened so far:
My first attempt to build a Yagi-Uda antenna was based on a design by Paul/KD5IVP. It worked, but had some crucial flaws for my endeavors. It was a 3-element antenna made out of piano wire and a carbon fiber arrow as a boom. Very small and lightweight indeed but in high winds/gusts the elements were flapping like a seagull during take-off. It’s demise came on it’s second outing… the arrow broke in half while bushwhacking up a mountain and I lost some of the piano wires in the woods. To read more about it and to see it in action check out this post.
I then moved on to a tape measure 3-element antenna based on a design by Joe/WB2HOL. It worked well and accompanied me on several activations – even a few 14ers (Summits higher than 14’000 ft / 4267m). My main gripe with this antenna is that it is delicate to transport as well. The steel tape gets kinked easily since the antenna is strapped to the outside of my backpack. It’s rather easy to replace the director and reflector, but soldering the coax to the steel radiator is another story. It turned out that this design is also vulnerable to high winds and your arms start to feel the weight after a few minutes without support. You can see the antenna in action in this video, around 3:30 into the clip.
The one?
I continued my research for a suitable 2m Yagi-Uda which would fit my requirements:
- Lightweight (but sturdy enough to withstand high winds)
- Easy and save to transport
- Easy to build (even for me)
I eventually stumbled onto IZ2UUF’s Website – an Italian radio amateur who enjoys hiking and playing with radios as well. He designed an 4-element Yagi-Uda weighing only 80 grams (~2.9 ounces)!! All elements fit into the fiberglass boom (fishing rod) for easy transport with no matching network necessary. The description to build the antenna focused on the critical parts with excellent pictures to support the instructions.
Davide/IZ2UUF modeled the antenna with 4NEC2, a free antenna modeling software package. Since he shared his input file with me, I took the opportunity to download the free SW and to learn more about antenna modelling. After a few more e-mail exchanges with him I was convinced by his design and started to source all the parts.
I did not have afiberglass fishing pole available and opted to use a plastic one I had lying around. Davide is using aluminum welding rods for his elements which I could not find at the desired length/diameter here in the US. I therefore ordered aluminum alloy 6061 rods instead (1/8″ x 6′ ) from a supplier in IL (for details see the resource section below). My build also differs in the connector (BNC instead SMA). All these changes resulted in a slightly heavier (194 g / 6.8 ounces) first version compared to Davide’s antenna. My boom alone is heavier than Davide’s complete antenna (96 g / 3.4 oz). However, I am planning to improve/reduce the weight in version two.
I had a chance to use the antenna over the week-end during the CO-14er event. All I can say so far is that it worked well and that the weight is not an issue at all… huge improvement to the tape-measure version.
For more pictures, a weight comparison and resources head over to my blog.
73, Matt/KØMOS
Harold’s JA7HJ tower was not your average tower
I meet some very interesting people in radio circles. My friend Harold Johnson (W4ZCB) is undoubtedly one of them.
Last year at my local ham radio/DXer club meeting, members were asked to bring photos of shacks and rigs, and describe our evolution as ham radio operators. In the series of photos that arrived at the following meeting, one in particular stood out: Harold Johnson’s radio tower in post-war Japan.
Johnson’s tower stood almost thirty feet tall and supported a 20 meter Yagi which you can see in the above photo. Johnson, who at the time operated under the callsign JA7HJ, also had a little ham shack built. The shack materials–including the tower, Johnson recalls–cost him “three bottles of Scotch for the army quartermaster…I paid the Japanese builder $15 or $20 for the complete enchilada.” This tower was built entirely of wood: the vertical members were 2′ x 4’s, the slats were 1′ x 3’s.
Of course, the tower didn’t have a mechanical rotor; instead, Johnson climbed inside the tower, lifted the wooden boom, rotated it manually, and placed it back on the uprights.
When asked how he powered his station, Johnson pointed to the wheeled generator in front of the radio shack in the photo. “The generator was called a B6B–it produced 24, 120, 240, and 480 volts, and was rated 10 kW.” When I asked how he managed to procure the generator, he replied that he “borrowed it from the flight line, which was about 300 feet away.”
I always enjoy hearing personal histories in radio and I didn’t doubt for a moment that Harold Johnson’s would be intriguing, so I asked if he’d tell us how his interest in radio began. So, here’s Johnson’s story in his own words:
As a preteen, (and poor as a church mouse during our previous
Depression), I would visit my aunt and uncle in the summer, likely due to the fact that they were farmers and had food to eat. They owned an old Philco radio that had shortwave bands and I was intrigued with the phone amateurs on the 80 and 20 meter bands. Often, I could hear both sides of the conversation, after I found out that they were on various different frequencies, being crystal controlled back then! My…How times have changed.In high school, I found another afficianado, and can recall melting “Woods metal” in boiling water and floating a piece of Galena on it until it returned to a solid and [thus] made my own crystal set. WWII had started by then, and I would listen to the ground-to-air communications between ships in Lake Michigan and pilots taking off and landing on them. Great DX, perhaps 10 miles away.
In 1943, I had graduated from high school and joined the US Army Air Corps. Went through training and was still in training (…to be a pilot until they counted airplanes and pilots and decided they had enough of each […so instead] turned me into a B-29 gunner). The war was over whilst [I was] still in training and I “retired” in November 1945. Went home and found my high school sweetheart, married, went back to school to finish my education and started the Johnson family. Still married, and
to the same girl. What a sweetheart to have put up with me all these years. [No kidding, Harold!]Went back in the US Air Force in 1949, this time became a pilot, and just in time to go to Korea for a year. However, during training, had to learn the Morse and if you learned to 13 WPM, you had a free hour and didn’t have to attend class. That overcame my obstacle to amateur radio, and I took the exams in 1950 and became W9PJO. Our rules at that time were that you had to hold a “class B” ticket for a year before you could take the “class A” exams. That year I spent in Korea and Japan and managed to obtain my first foreign call, JA7HJ.
Returning home to wife and by that time two children, I took the class A exams and became W4ZCB. I decided that I enjoyed flying, (at least most of the time), and decided to make it a career. The ensuing years, I was always on and in the air, and usually spent the winters in Alaska and the summers in the Canal Zone, anything to practice how to be miserable. Lebanon in 1958, Vietnam in 1968 and by 1969 decided that I should start doing something else before my luck ran out.
During my last 4 years of service I flew an Army four star around the world four times. Fortunately he was Ted Conway, W4EII, and we mutually enjoyed operating under a couple dozen different call signs from a lot of exotic (and several not so exotic) places. Had G5AHB back when the 5 was reserved for foreign nationals. We were good friends after we both retired (on the same day; I always liked to say that he couldn’t stand to serve without me) until his death in 1990.
I started a small company manufacturing electronic test equipment for public utilities; spent the next 20 years doing that (and enjoying a much more stable life with family and radio.) Managed to work all the countries (entities these days) there are, win a few contests from a contest station I built and operated for 10 years. (80, 40, and 20 in the front room, 15 in one bedroom and since 160 and 10 were seldom open at the same time, they shared the other bedroom. To change bands, you just changed chairs. Five big towers and Yagis, a VERY high maintenance hobby in the lightning prone state of Florida. (Let’s not mention hurricanes!)
Retired again to the beautiful mountains of North Carolina in 1986. A much more modest station these days, but active on all the HF bands. I really enjoy building homebrew radios and maintaining daily schedules with friends worldwide. Can be found daily on 21.203 with G3XJP and often joined by other builders of the magnificent PicaStar transceiver designed by him. Sixty-three years a ham, still enjoying it. It’s guided my careers and interests. What a wonderful hobby!
Over the past few years, I’ve gotten to know Harold Johnson; I must say, he has to be one of the very few hams I know who knows the inner workings of tube/valve radios as well as he does the highest tech radios on the market, a rare talent indeed. If you’re trying to learn a bit more about the BC-348 series of radios and trying to diagnose a problem with it, Johnson’s your guy. If you’re trying to build an SDR from scratch, he’s also your guy. And clearly, if you want to hear a fascinating account of a life influenced by radio, this is most definitely your guy.
Thanks, Harold, for letting me share your story!
Check out Harold Johnson’s website by clicking here.
5 Foot Diameter Magnetic Loop Antenna
A bonus picture here. The one on the left is a 3 foot in diameter loop.
Note: The little box at the bottom of the small one contains an air variable capacitor for tuning.
Compare it to the 5 foot in diameter loop on the right. ‘
I made a QRP CW contact with this mag loop from right where it stands in my drive way.
Home made cap clamps. The clamps are soldered to keep the contact resistance low.
This is very important with High Q antennas.
Russian capacitor. It is available at E-Bay for about $150
Where would hams be without PVC pipe!
This stand is made from 2 1/2 inch sewer pipe.
This is a fun antenna to build and use. I made my first contact with W9GY this afternoon on 20 meters. I used 5 watts, he used 10. RST out was 459, RST in was 579. The antenna was in my drive way in front of the garage that you see here. And Jeff was in Indiana. What a hoot! Making contacts on a home made antenna is great fun. The parts are readily available and with a little planning and shop time you can have a Magnetic Loop antenna to play with.
This is my second Mag Loop. The first one is 3 feet in diameter and covers from 20 through 15 meters. I’m planning another for 17 meters through 10 meters. Mag Loop calculator is available at http://aa5tb.com/index.html
Yahoo has Mag Loop groups that are very helpful to get you started. http://groups.yahoo.com/group/MagLoop/
and http://groups.yahoo.com/group/MagneticLoopAntenna/
Copper foil or strapping is available at http://stormgrounding.electrical-insulators-and-copper-ground-bars.com/copper-foil-2.html
If you’d like more information about Mag Loops, please feel free to contact me. [email protected]
73 De AA1IK
Ernest Gregoire
























