Sunday, January 20, 2008
HAARP Moon Echo Experiment--Slight Return
On the second night of the experiment, January 20, 2008, I copied signals at 6.7925 MHz from 0130 until 0139 EST, at which time the signals abruptly stopped and I subsequently received nothing. (nothing audible and nothing on the spectrum readout, which is much more sensitive.) I monitored continuously for another 15 minutes and then spot checked until 0230 EST. I moved to 7.4075 MHz and also copied nothing there.
Saturday, January 19, 2008
HAARP Moon Echo Experiment
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.
Click on the photo, then on "all sizes" for a larger image.
Click on the photo, then on "all sizes" for a larger image.
Thursday, January 17, 2008
Wednesday Night 40m Hellschreiber Net
Well, 40 meters was being very ornery tonight at net time of 9 PM EST. Here in West Virginia I had no copy, no signal at all on net control or anyone else except I had about a 50 percent copy on WB2HTO. I saw the name Leslie go by, and I believe I saw a QH in AL. At 9:35 PM EST I checked in again and the band had greatly improved. I had net control, about 90 percent copy on WB2HTO but work got in the way and I did not have time to check in.
I'll be there next week unless work overrides my plans. Thanks to W8LEW for running the net.
I'll be there next week unless work overrides my plans. Thanks to W8LEW for running the net.
Sunday, January 13, 2008
Happy 60th Birthday to the Transistor !
In honor of the 60th birthday of the transistor, here are some photos:
The first transistor was developed in 1947 at Bell Labs by Shockley, Brattain, and Bardeen and it was made from germanium not silicon. Germanium was used through the 50's and into the 60's before being completely replaced by silicon transistors. 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 micro in your average personal computer contains about 500 million transistors. The latest dual-core server processors contain about 800 million. Your typical desktop or laptop computer today contains over 2 billion transistors in all. The simple transistor has come a long way.
The First Transistor
Replica of the First Transistor
Diagram of the First Transistor
Replica of the First Transistor
Diagram of the First Transistor
The first transistor was developed in 1947 at Bell Labs by Shockley, Brattain, and Bardeen and it was made from germanium not silicon. Germanium was used through the 50's and into the 60's before being completely replaced by silicon transistors. 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 micro in your average personal computer contains about 500 million transistors. The latest dual-core server processors contain about 800 million. Your typical desktop or laptop computer today contains over 2 billion transistors in all. The simple transistor has come a long way.
070 Club PSK Fest Recap
Well the PSK Fest was fun. I started out QRP but got no bites so switched up to low power (50 watts) and worked 117 uniques on 40 meters, spending almost all of my time between 7070 and 7073 kHz. I made a couple of friends along the way and we're going to set up skeds to try out more of the digital modes. I checked down at 7035 a few times but there was no workable DX from here in West Virginia. I worked a couple of Americans down there at 7035 and noticed that a couple of CW operators were intentionally QRMing the PSK signals. There seemed to be plenty of space on the band so I'm not sure why that would be.
I did notice something unfortunate. Quite a few PSK operators were overdriving their rigs with signals 300 Hz wide. One signal I saw had repeating audio harmonics that spread his signal across 1,500 Hz. One of the 300 Hz wide operators asked me how his signal looked and I told him, but he didn't seem to care. I wonder if those operators realize that distortion and wide signals actually harms their readability, in addition to spoiling the band.
I'm looking forward to the next digital contest!
I did notice something unfortunate. Quite a few PSK operators were overdriving their rigs with signals 300 Hz wide. One signal I saw had repeating audio harmonics that spread his signal across 1,500 Hz. One of the 300 Hz wide operators asked me how his signal looked and I told him, but he didn't seem to care. I wonder if those operators realize that distortion and wide signals actually harms their readability, in addition to spoiling the band.
I'm looking forward to the next digital contest!
Friday, January 11, 2008
070 Club PSK Fest
The PSK Fest starts tonight at 1900 EST. The contest is sponsored by the Penn-Ohio DX Society (PODXS) and runs from 0000z to 2359z January 12, 2008. I prefer PSK63 for contesting but this contest is PSK31 only.
I plan to run QRP single band (40 meters). If conditions are terrible on 40m like they were last night I may switch up to the low-power class. I hope to see you out there.
Contest info is here: http://www.podxs.com/html/pskfest.html
de KW2P
I plan to run QRP single band (40 meters). If conditions are terrible on 40m like they were last night I may switch up to the low-power class. I hope to see you out there.
Contest info is here: http://www.podxs.com/html/pskfest.html
de KW2P
Thursday, January 10, 2008
Dial + Audio Offset
Modern sound card digital modes have introduced a layer of ambiguity when it comes to citing an operating frequency. Some operators quote a single frequency which means their dial frequency and assume an audio offset of 1 kHz. Some operators quote a single frequency that means their actual RF emission frequency. Others specifically quote their dial and offset, such as 7070+1500.
It would be great to quote just one frequency--the actual emission frequency--but today there is confusion with this. If a digital operator quotes a single frequency and we do not know that operator personally and know his or her practice (their personal favorite audio offset), we cannot be sure what is meant. So the only sure-fire way to remove all doubt is to cite dial+offset. Then we know for sure what is meant. We know that an unstated audio offset is not being omitted.
It would be great to quote just one frequency--the actual emission frequency--but today there is confusion with this. If a digital operator quotes a single frequency and we do not know that operator personally and know his or her practice (their personal favorite audio offset), we cannot be sure what is meant. So the only sure-fire way to remove all doubt is to cite dial+offset. Then we know for sure what is meant. We know that an unstated audio offset is not being omitted.
40m Hellschreiber Net
Well that was fun. I checked into the Wednesday night 40m Hellschreiber Net, 7077 kHz +1000 Hz audio at 9:00 P.M. EST (0200z). Net control was Lou Wulfekuhler, W8LEW, in Lansing, Michigan. The net started out in Feld Hell but conditions were poor so we switched to FM245 and got much better results. There were checkins from Delaware, New Mexico, and Hawaii, although I could not copy the fellow in Hawaii. Thanks to Lou for running the net. I'll be there next week if I can.
Wednesday, January 9, 2008
Monday, January 7, 2008
First Sunspot of Cycle 24
Yippee! The British Solar Observatory announced that the first sunspot of cycle 24 (the next sunspot cycle) appeared in the northern hemisphere on January 5th. It's a good time to be getting into ham radio!
Thursday, January 3, 2008
Strange PSK63 Effect
This has happened three times now on three different nights and three different contacts. Here's how one instance went: I was calling CQ on 40m PSK31 and Fred, K5QBX was trying to reply. His signal looked sort of okay but just wasn't enough to read. It took two attempts before I even got his callsign. It was enough for a contact but not enough for a decent conversation. It was late and the band was empty so he switched in the amp and dialed it up to 500 W PEP. His signal was still perfectly clean on the waterfall and IMD was -21 dB, and now I had him at about 98 percent. So then I suggested, just for fun, switch to PSK63 and drop back down to barefoot. He did, and guess what? I had him at 95 to 98 percent. He had never tried PSK63 before and was very pleased. We had a long chat.
I've observed this same phenomenon two other times where on a weak contact on a noisy and weak 40m band at night, PSK63 provides better readability than PSK31. Of course, this makes no sense. PSK63 should be 3 dB poorer than PSK31 and yet I observe the opposite and then some.
I am at a loss to explain this effect. Perhaps the noise or path characteristics on 40m are such that PSK63 modulation is harmed less than PSK31? I'd be interested to hear any theories about this and maybe someone can duplicate my results.
73 de KW2P
I've observed this same phenomenon two other times where on a weak contact on a noisy and weak 40m band at night, PSK63 provides better readability than PSK31. Of course, this makes no sense. PSK63 should be 3 dB poorer than PSK31 and yet I observe the opposite and then some.
I am at a loss to explain this effect. Perhaps the noise or path characteristics on 40m are such that PSK63 modulation is harmed less than PSK31? I'd be interested to hear any theories about this and maybe someone can duplicate my results.
73 de KW2P
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