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Re: TZ6RD operation..

Gene AA6NP wrote:

I also made a second contact just to be sure I was in the log ok. But only after he called CQ without a reply. I was only 95% sure the first qso was ok due to qrm. A lot would be gained by taking a bigger antenna or more watts on these dxpeditions, as well as improving our own receive capabilities.

Wayne W9AE replies:

The DX operator has a lot of control over this situation.  The DX operator is usually working full-duplex, so he should be able to hear when he is being QRMed.  He should repeat the callsign as many times as it takes to be heard clearly without QRM.  Twice is a good minimum.  A few more seconds spent to reliably acknowledge the callsign on the FIRST exchange will eliminate the stations anxiously calling over and over asking for their callsign to be acknowledged again.  QRM may have affected my hearing, but several times I thought I heard Doug say things like "XYZ you're in the log".  XYZ might go away more quickly if Doug had said "W5XYZ W5XYZ you're in the log". 

I don't understand why so many satellite DXpeditions are having trouble with their uplink.  Doug told me that one of the Spanish operators supplied all the coax cables for the Mali operation.  So maybe he had a bad cable?  I believe he had a 60W amplifier for the 435 Mhz uplink.  His uplink should have been better than it was with 60W to a 7-element yagi.

I think I had an excellent uplink during my FG/W9AE operation, and the same portable setup gave me a good uplink when I worked the Bali station on Monday.  That's 50W (minus a dB of cable loss) to a 7x7 Arrow yagi, 39 inches long.  My portable uplink is never "LEILA bait", but I can hear it clearly on my 2-foot dish.

But I did 3 things to improve the audio:  First, I use an external speech processor because the FT-847 speech processor doesn't work in satellite mode.  Second, I use a Heil HC-5 microphone which is much more intelligible than the stock Yaesu hand microphone.  Third, I tweaked the FT-847 LSB carrier insertion point menu to reduce bass response and extend treble response.  This allows more power to go to higher audio frequencies that contain most of the intelligence in speech.   When using a marginal uplink on SSB it is essential to have clear punchy audio, and not waste power on bass frequencies.

Yesterday I received some interesting comments from Neil regarding his AO40 operation in Lesotho and Swaziland.  His most amusing complaint was that a few people insisted on sending complete details about their station, even though there was obviously a pileup and he was attempting to get as many stations in the log as quickly as possible.  He seemed surprised at the slow rate that contacts were made on satellite compared to on HF (this was his first time EVER to make satellite contacts).  He was also surprised at the number of satellite operators who were unable or unwilling to use CW (he operates in VHF contests where CW is widely used).

Overall, I think the recent satellite DXpeditions have done just fine.  They made lots of contacts despite hardware problems and local obstructions.  No DX operator is perfect, and we should always keep in mind that they are human and they are doing this for fun.  Every DX operator has their own technique, style, and temperament.  Such is life.

Wayne Estes W9AE
Mundelein, IL, USA
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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