Saturday, July 09, 2005

My first satellite contact

As you may have noticed from looking at my other posts and my profile, I am an amateur radio operator. One of the really neat aspects of amateur radio is the satellites that "hams" launch into orbit. I made my first contact via an amateur satellite. The satellite's designation is AO-51, but it is also known as Echo. In the mode that I used today the satellite as a FM repeater. It listens to my transmissions on the 2-mter ham band, specifically at 145.92 MHz, and re-transmits them at 435.3 MHz in the 70-cm band. My transmission consisted of saying my callsign phonetically followed by the word "handheld" and my grid square. I was using a Kenwood TH-D7A(G) five-watt handheld radio in conjunction with a dual-band Arrow Antenna. At least two stations acknowledged my transmission along I believe one was asking for a repeat of my grid square (which is EM89). What is most impressive is that this satellite is a cube less than ten inches on each side flying at an altitude of 850 kilometers (about 530 miles), and I think that it was transmitting to me with about one watt of power (if I am reading the chart on the AMSAT page correctly). I tried to make a contact on two occasions last night. The first contact was cut short by a dying battery on the handheld radio. For the second attempt, I had a fully charged battery and I heard the satellite fine, but I forgot about the 67 Hz PL tone that is required to access the satellite's repeater. I used my copy of Nova for Windows for tracking the satellite.

Actually this contact was not my first satellite contact, but it was my first voice contact. Several years ago when the Russian MIR space station was still orbiting, it had a packet digipeater on board. I used the same radio to send a packet to the digipeater. Seconds later I saw the message "My packet" flash on the display of the radio. That meant that my packet had been repeated. I used an AEA telescoping whip antenna on the radio for that contact.


Northern Lights Software Associates (makers of Nova for Windows):

Sunday, May 29, 2005

Amateur Radio things

One of my other hobbies is amateur radio. This past weekend I attended what is most likely the largest amateur radio gathering in the world, the Dayton Hamvention, in Dayton, Ohio. Most of the amateur radio manufacturers and dealers are there and the are several hundred (maybe even a couple of thousand) people selling or swapping items at the outdoor flea market. For the most part, I didn't see anything new or earth-shattering within the amateur radio world, but during my last hour of attendance, I noticed that Icom had unveiled a new HF/VHF/UHF transceiver, the IC-7000. This radio looks quite a bit like the IC-706MkIIG, but has a color display and a bandscope. It apparently also incorporates IF-DSP. I had previously been researching the Yaesu FT-897D as I would like to start portable operation, but I think that with the right choice of battery, I could use a radio such as the IC-7000. It would just be a matter of lowering the RF output. The Yaesu 897D and the Icom IC-7000 are both 100W radios on HF, but the 897D only outputs 20W when on its internal battery packs. I think that a Buddipole system and a good HF/VHF/UHF antenna analyzer would round out a decent portable station. Now I just need to work on the Morse Code so that I can get out of the no-code Tech level.