Rich,
Thank you for posting this. I never thought to mention the Memory Tune feature, which is, indeed, very useful. Like you, I began using the VX-7R on the satellites because it is what I had at the time. I have no intention of trading mine until some company brings a new radio to market with full duplex capability.
It permitted me to earn Satellite VUCC, all handheld, and the AMSAT Achievement Award - the latter using only 50 mW contacts (21 states, Mexico and Ontario) made on the same set of 2 AA Duracells. I also made four contacts through the ISS U/V repeater over the weekend with it.
As you say, it may not be the best for the satellites. But it's more-than-good-enough for me.
Also, here's a tip that, I hope, you'll find to decrease your stress level on every pass. Get a small digital voice recorder that has a time counter, and just record your passes - even if it's just the wild sound. I have done that since Day 1 with a small recorder I can clip to my shirt collar or pocket. I don't worry about writing down calls at all. I start the tape on an even minute (e.g., if my AOS is at 23:15:12, I start the recorder at 23:12:00. I speak that time into the condenser mic, and include the satellite I'm working. After the pass, I just come in and replay the tape, which allows me to synch calls and times correctly for logging purposes. It also gives me a chance to MP3 clips from contacts I want to keep. The "wild sound" quality isn't as good as having a full duplex radio and having the recorder connected to the audio out jack, but it's the only way to get boths sides of a contact since the VX-7R operates only semi-duplex.
73 to all,
Tim - N3TL AMSAT Member No. 36820 QRP-ARCI Member No. 5547 ARRL Member No. 7027180 Athens, Ga. - EM84ha -------------- Original message from "ki6rrq" [email protected]: --------------
I am currently using a Yaesu VX-7R (not the best for satellites, also using it because that's what I had)for the ISS and the FM birds. I don't know if this will help anyone but I found using the memory tune feature is very helpful for working the Doppler, I don't know if your TH-F6A or many other HT's have it but I think it saves me a little time and hassle, when the receive frequency is on 2 meters, anyway. I know the FT-60's have it too.
For AO-51, I save a memory channel with the 2 meter receive freq and then add the odd split or odd band split to the TX part of that memory and the pl where appropriate ... Then when I use it out in the field on my Arrow II, I bring up the memory and then select the memory tuning mode, which I guess is similar to the VFO mode but keeps the TX side in place and allows me to tune the RX frequency up and down to adjust for the Doppler and all I have to do is push the PTT when I make my call and the 2 meter TX frequency is automatically used. I don't even have to hold the radio, just get my fingers to the dial tuning knob, a few times during the pass. (tripod mounted radio, per my qrz.com) I haven't found its worth worrying about the Doppler on the 2 meter side, since the radio only does 5k at a time. After trying numerous methods, I found this to be easiest, with everything else you have to deal with on a mobile sat. operation; writing calls down, keeping the antenna on the bird, testing for polarity alignment, dealing with the dark, oh yea what was that guys call again... Its like an Apollo 13 rescue mission to get it all done... except its always a fun ride... LOL, I needed to simplify everything.
Best Rich KI6RRQ
Message: 2 Date: Sun, 7 Dec 2008 13:42:01 -0500 From: "Jim Leder" Subject: [amsat-bb] Re: Kenwood TH-F6A for AO-51 / SO-50?? To: "Amsat" , "Guy Brauning"
Message-ID: 547D1F8574B04DDC801A1FD71EB224FE@Toshibalaptop Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original
I have used my Kenwood TH-F6A along with an Arrow antenna, and IMHO it works
just fine. You do need to get it programmed right and you need to get used to switching between VFOs as you track the satellite and the Doppler effect on frequency. It is NOT a full duplex radio like the W32A, and you will not be able to hear yourself, but I have never felt that's been a problem.. I programmed mine to transmit on one VFO (uplink) and be able to receive on several different frequencies (downlink) on the other VFO. On the transmit VFO, the squelch is closed all the way, while on the receive VFO, it's open all the way. So, VFO A is set for uplink of 145.920 on memory channel 150 and on memory channels 152-153 I have them programmed for 435.290 and 435.295 (downlink which is in VFO B). 154 is center frequency of 435.300 and
of course 155 and 156 are set to 435.305 and 435.310. By switching between VFOs I can change downlink channels/frequencies to fit the Doppler shift. A little cumbersome, but that little radio works very well. You can follow a similar scheme on the QRP channel of AO51 (mine is 160-166) and SO50 (mine is 170-176-get the picture). I have made several contacts with it on the QRP
channels but have had no luck on SO50, which is a lot more difficult satellite to hear. I'm using it because it's what I had, and I'm happy to say with a little use and practice you quickly get the hang of it. Of course, either the W32A or the Kenwood TH-D7A do FULL duplex, but both are no longer in production. Hearing yourself is nice, but not necessary.
Jim Bob Buckeye AKA **** Jim Leder**** K8CXM since 1961 IBM retiree since 1999
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