Hi Jeff!

1. The fact that your downlink antenna is always vertically polarized

rather than steered to the polarization of the satellite.

I know the vertical antennas have a null directly overhead, but it doesn't make sense to me why I can hear TCA-LOS fine, but AOS-TCA is hard - and that was on an 87 degree pass.

2. The position of the antenna on your vehicle could also have a huge

affect as well as the orientation of the vehicle to the satellite during the pass.

We were driving in a straight line on the interstate at the time of the pass(s), so the vehicle was generally oriented the same direction.

The FTM-350AR is full duplex, but it also has a more sensitive receiver than the TH-D7A, so I have used it for receive. I could still use it for uplink as well, but I had the ARR preamp hooked inline, and you obviously don't want to transmit 2m through it. In the short term it was just easier to use the TH-D7A for uplink. Why do you ask?

73!

Zack KD8KSN

-----Original Message----- From: Jeff Moore Sent: Friday, May 13, 2011 8:53 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: KD8KSN/M & a question

I could be wrong, but I suspect a couple of things:

1. The fact that your downlink antenna is always vertically polarized rather than steered to the polarization of the satellite.

2. The position of the antenna on your vehicle could also have a huge affect as well as the orientation of the vehicle to the satellite during the pass.

Isn't the FT-350 full duplex capable?

73,

Jeff Moore -- KE7ACY

----- Original Message ----- From: "Zachary Beougher" zack.kd8ksn@hotmail.com

Hi All,

Thanks for the QSO during my few mobile ops the past couple days – and for your patience. We had three small road trips planned for various reasons Wednesday-Friday, so it provided a great opportunity to try the mobile equipment out, find out what combinations work better than others, etc., etc., so I can perhaps get on the air a little more while mobile during vacations and such. I will be uploading all QSOs to LoTW within a day or so, and if anyone wants a card just email me the QSO details. I did have a question:

One consistent issue I found while operating is that I could just barely hear a bird from AOS-TCA, but from TCA-LOS I could hear fine, even down to 10-5 degrees. I am not understanding why I can’t hear one side of the pass, but I can hear the other fine – almost full quieting with the preamp. I should also mention that I experienced this issue on AO27 and SO50, not AO51. I would thinnk it would be a polarization issue, but that still doesn’t make sense to me. My main setup consisted of:

Uplink: TH-D7A (7w plugged into 12VDC), Comet CA-2x4SR mag for uplink.

Downlink: FTM-350AR, ARR SP432VDG preamp on battery or 12v, Arrow duplexer (440 side hooked up which solved my desense issues so I could work full duplex), and a 19” quarter wave mag.

I had posted here about a month or so ago wondering if intermod would be an issue using a preamp while mobile. I monitored about 7-8 passes over the past three days while mobile and intermod was never an issue. I did have a little bit of alternator whine on the FTM-350AR’s receive, but it was very minimal. That could be solved by running the cables directly to the battery. Since we were in the family vehicle I just used the cig lighter (I know that’s not a good idea, but it was only for a couple days).

73!

Zack KD8KSN _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb