brainwagon

The amateur satellite AO-7 was launched on November 15th, 1974. It was thought to be lost for years, until recently when chemistry changes in the batteries increased the resistance so that now when the satellite is in sunlight, its transponder is directly powered by its solar panels. While reading a post to the AMSAT-BB today, […]

Well, I was awake for a decent daytime pass of NOAA17, so I wandered out into my front yard, and recorded the pass. It was a westward pass, covering from Canada all the way down to Baja California in the south, and was reasonably noise free over a great amount of it. I hauled it […]

I haven’t had the time to record some of the NOAA17 passes during the day, but once night falls, I’ve managed to record a few passes. Tonight, I decided not to use my Yaesu VX-3R, but instead tried to record the pass from my old Radio Shack PRO60 scanner. While I recorded a bit less […]

A bit of image processing with gimp yielded the following on a night time pass.  It wasn’t particularly good with respect to noise:  on the night passes the contrast is pretty low , so you get difficulties  when you try to extract good images.  Still, I’m not displeased…

I was monitoring a routine pass of AO-51 this morning, just listening to some rag chewing, not really diving in myself, until we heard XF4YW calling. One of the regulars identified him as a rare DX, so we all tried to work him from DK48. I had no idea where DK48 was, or that XF4YW […]

Well, I’ve been experimenting a bit more with some weather satellite reception, and on the off chance that anyone cares, I thought I’d write down some of what I learned. Last night (after dark) I decided to record an NOAA-17 pass. This time, I used my Yaesu VX-3R, which has a wideband FM setting, and […]

Okay, this isn’t that impressive, but let me explain. Larger version of the same… I recorded about 4.5 minutes of audio from one of the weather satellites, using my small pocket recorder and a Kenwood TH-D7A. In most respects, I shouldn’t expect anything good to happen. I’m using a cheap little voice recorder. I’m using […]

Terminal node controllers are the “classic” approach to doing packet radio. They are basically dedicated modems that are used to implement a set of features that allow you to send and receive AX.25 formatted frames over amateur radio. The thing is: they are getting harder to find. My TH-D7a has a fairly sophisticated one built […]

I mostly just wander out and wave my antenna around when I work satellites. Someday, I might want an automated system, and this can be built for less than a hundred bucks with stuff you can get from Radio Shack. Worth archiving. A PRACTICAL ROTATOR SYSTEM (APRS)®

I was experimenting with APRS messaging via GO-32 this morning, after being simply overrun by Mexican hams earlier in the morning on AO-51. W7KKE runs a GO-32 SatGate in Lincoln City, Oregon (a place I’ve visited many times) and was apparently listening when I messaged him this morning via my TH-D7. I wasn’t using a […]

I looked at oscar.dcarr.org, and noted that the ISS packet radio feed appeared to be back up. We had a 15 degree pass to the west (the most favorable direction, toward the east I have a S5 noise source), so I went out and waved my antenna around, and got the following packets digipeated: From […]

Now that I have a DC power converter in my car, I am able to run some experiments. Last night I left my radio in my car and hooked up to my mag mount roof antenna, tuned to 145.825Mhz, the frequency which has been designated for use by the APRS system via satellites. NO-44, NO-61 […]

I’ve been interested in low frequency radio (so-called “lowfer” operation) for quite some time. Because of the incredibly long wavelengths, lowfer operation relies on efficient transmission techniques to overcome the problem of seriously short and inefficient antennas. Still, lots of interesting stuff going on under Part 15 regulations, and recently some experimental stations have been […]

I caught the westward pass of AO-51 tonight that began at 9:18pm local, and caught K7WIN (DM41) calling by his lonesome on the satellite.  After a bit of juggling with my antenna, I called out to him and got a QSO for the logbook.    I heard another call, but lost it in some kind of […]

One of the reasons that I chose the Kenwood TH-D7A(G) as my hand held transceiver is its integration with packet radio. It includes a TNC (that’s terminal node controller) that works at either 1200 baud or 9600 baud. This allows it to exchange digital information over amateur radio frequencies. It also has the ability to […]