Poor SuitSat

When originally hearing about SuitSat, the satellite made out of a spacesuit, I didn’t figure I’d bother trying to monitor it during its brief 2-4 day window of existence. Besides, I had just run across a slashdot post pointing to an ABC News article proclaiming SuitSat a dead animal.

So while tooling around the ham radio IRC channels on EFNet during the wee hours last night, I ran across Deeply (KD7YVV) and thinkpol (K5BCT) in the process of trying to hear SuitSat. Apparently it wasn’t dead afterall. They informed me that there had actually been some reception reports.

I did a quick once-over of the NASA SuitSat article and learned that it had the same orbit as the ISS (International Space Station). I loaded up JTrack to follow SuitSat’s current position, and used JPass to find the next time it would be in my sky’s view. Before its next pass, I threw a 1/4 wavelength telescoping antenna on my Kenwood TH-F6A, killed the squelch, tuned to 145.99 MHz, and pointed the antenna toward the south sky.

And then … I heard stuff!  But not the right stuff.

Hmm, I heard varying intermittent packet bursts, ranging from full scale to barely audible. That didn’t sound right. And I knew from my mid-90s experience of digipeating through the Mir space station that I should probably be hearing doppler shift on the signal. There was none. This sounded local. I decided to read the NASA article more closely and learned that SuitSat is only transmitting voice and SSTV (Slow Scan Television). So what was I hearing?

Since these signals did actually come and go with the orbit of the space station, I checked the NASA ARISS page (Amateur Radio on International Space Station). It turns out the uplink frequency for the ISS packet station is 145.99, same as the SuitSat frequency. So these signals were local stations trying to digipeat through the ISS packet station.

Okay, that’s a little inconsiderate to somebody trying to hear SuitSat during its short life, but I didn’t really care – I now had the new goal of trying to hear ISS on its downlink frequency of 145.8, or at least see if I could tell which stations were trying to digipeat through it on 145.99.

I moved the telescoping antenna to my TH-D7AG with its built-in TNC, already configured with my APRS info. I put the lowly stock antenna back on the TH-F6A, tuned both radios to 145.8, and headed for the back porch. As the next pass moved across my northern horizon, I could hear ISS surpsingly well on my F6A with the stock rubber antenna. But it was not nearly as present on the D7AG. Bummer. There were a couple fairly strong packets, but the D7AG was unable to decode any of them. Incidentally, I was totally surprised by how deaf the D7AG with a 1/4 wave antenna was compared to the F6A with its stock antenna.

The next pass would go up through Washington state and across northern Canada. I couldn’t hear anything on either rig on either frequency that time. Neither could Deeply or thinkpol. Time to give up.

So SuitSat was a bust. But now I have the urge to try ISS with a bigger antenna and radio. The last time I wanted to try something with a bigger antenna and radio, I ended up dropping a couple grand on HF equipment. Oh no!



  1. Hi Lance,

    It really depends on how badly you want a TNC or APRS built into the radio. The TH-D7AG is obviously the only choice for that.

    Otherwise, my opinion is that the TH-F6A is a much better radio. It’s just a more mondern feeling rig with more bells and whistles. It’s a lot smaller and lighter, practically pocket-sized. It doesn’t get very hot when transmitting for long periods. The receiver covers 100kHz–1300MHz and includes AM and sideband modes. The HF ham bands can be received pretty well if you use a longwire or an active antenna. And the 220 band is included for transmit. We only have a couple 220 repeaters in this area, but it’s nice to be able to work them if I want to. Certainly more useful than tribanders with 6m, in my experience anyway.

    As for the D7AG, it only covers 118–174 & 438–450 MHz on receive, and only FM. On the dual VFO, you can only monitor one VHF and one UHF freq at the same time, which feels kind of clumsy. The display is harder to read than the f6a. The battery indicator is somewhat goofy and it’s hard to really tell how much battery is left. The radio basically looks and feels like it’s one generation older than the f6a. On the upside, the TNC is really cool, especially if you’re into APRS at all. And I believe it uses the same accessories as the popular TH-G71A, so things should be easy to find for it. (I have yet to buy any accessories for it besides the computer serial cable)

    Good luck! Lemme know what you end up getting…


  2. I’m trying to decide between the TH-F6A and the TH-D7AG. You are one of the few people that I have found on the net who appears to own both. I’d love your feedback.


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