After an interruption in ham radio activities and blog entries, I am back on the air, more or less. The interruption was due to several months of planning and executing a move to Guatemala and then getting settled here in my new digs and setting up a basic radio shack. At the moment I am only using a 26 foot vertical wire supported by a tree so my signal is not very good but I’m out there on PSK and Hellschreiber. You can usually find me evening and nights from 7070 to 7074, signing TG9/KW2P. Give me a call.
Once I collect the materials I plan to put up a 270 foot vertical loop. I have some tall trees here that will support a vertically oriented 80m full wave loop. I’ve had both vertical and horizontal loops of that size and they worked great so I expect good results, especially in the tropics where QRN can be a problem. The loop should improve things drastically but getting the materials down here takes some doing.
Tonight, the HAARP transmitter in Alaska was used to direct exceedingly powerful radio pulses (around 4 Gigawatts effective radiated power) at the moon at a frequency of 6.7925 MHz and I could easily receive the echoes from the two second bursts here on earth with my amateur radio rig.
Waterfall spectrogram of radio echoes from the moon.
Waterfall Spectrogram of Moon Echos. Click to view larger.
I wrote this article in 2008 to honor of the 60th birthday of the transistor, here are some photos:
The First Transistor
The First Transistor
Replica of the First Transistor
Replica of the First Transistor.
Diagram of the First Transistor
Diagram of the First Transistor.
The first transistors were developed in 1947 at Bell Labs by Brattain, Bardeen, and Shockley. They were made from germanium not silicon. Germanium was used through the 50’s and into the 60’s before being completely replaced by silicon transistors the we use today.
Those of you who are old enough will remember the first transistor radios in the 50’s. I do. Before long there was a competition over the number of transistors in the radio. Seven transistor radios, nine transistor radios–a big advertising deal was made over the number of transistors and the consumer was led to believe that more is better. Around the time I got into electronics, around 1959, 1960, I disassembled a 14 transistor radio and discovered that several of the transistors were fake! (had only two leads, or had the leads twisted together) A good radio can be built with six to nine transistors but they added several fake ones to boost the count and fool the public into thinking it was a better radio. This was a interesting lesson.
Throughout the 50’s and into the 60’s, transistors were made and packaged one at a time, and then assembled into circuits that you could see without your glasses and work on with your hands and a soldering iron. Plenty of transistors are still used as individual devices today, especially in high-power or radio circuits, but in 1959 Jack Kilby at Texas Instruments patented the first integrated circuit, where more than one transistor was fabricated simultaneously on the same substrate, along with components like resistors and capacitors to form a complete circuit that performed a function. The photolithography techniques used to “print” these circuits soon made it just as easy to make a miniature 20 transistor circuit as it was to make a single transistor and this was the way to the future. In 1971, Intel introduced the first microprocessor, a slow little 4-bit micro containing about 2,500 transistors. By 1975, Popular Electronics published the famous article that launched the personal computer revolution. It was an article on how to build a computer using Intel’s 8080 microprocessor. The 8080 contained about 4,000 transistors. Today, the microprocessor in your average personal computer contains billions of transistors. The simple transistor has come a long way.
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