Re: [Flexradio] VU5K With Dual Band Yagi
The VU is designed for weak signal work (high sensitivity), so there is more of an opportunity to overload down link. Try using a narrow bandpass filter on the down link to reduce the IMD mixing. Tim Ellison, W4TME Product Management, Sales Support FlexRadio Systems^(TM) 4616 W Howard Ln, Suite 1-150 Austin, TX 78728 Phone: 512-535-4713 Ext. 223 Email: t...@flexradio.com mailto:t...@flexradio.com Web: www.flexradio.com http://www.flexradio.com logo On 5/13/2012 6:11 PM, Paul Delaney - K6HR wrote: Is anyone using a 5000/VU5K with a dualband yagi for satellite work with any positive results? I recently put up a Gulf Alpha EZ Sat Dualband Satellite Yagi and it the performance has been very disappointing. The Flex RX downlink is completely 'overwhelmed' during TX on the uplink. The RX panadapter shows a flat line and a 10-20db rise during uplink TX effectively making my downlink signal unusable in trying to find my signal on the transponder. Before I ditch this antenna, I'd like to hear from anyone using a dualband antenna for satellite work, and any suggestions they might have. Paul Delaney - K6HR paul.hamra...@verizon.net http://k6hr.dyndns.org:8080 ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
Re: [Flexradio] VU5K With Dual Band Yagi
I use an Arrow Antenna for 144/433 work and it plays very well with TS-790A. At max 144 power (35 watts) it generates a few birdies on 432 downlink but I reduce power to about 15 watts and they are gone. The antenna is up about 15' with 25' runs of RG-213 to the rig. Bon, NZ5A Sent from my iPhone On May 13, 2012, at 5:11 PM, Paul Delaney - K6HR paul.hamra...@verizon.net wrote: Is anyone using a 5000/VU5K with a dualband yagi for satellite work with any positive results? I recently put up a Gulf Alpha EZ Sat Dualband Satellite Yagi and it the performance has been very disappointing. The Flex RX downlink is completely 'overwhelmed' during TX on the uplink. The RX panadapter shows a flat line and a 10-20db rise during uplink TX effectively making my downlink signal unusable in trying to find my signal on the transponder. Before I ditch this antenna, I'd like to hear from anyone using a dualband antenna for satellite work, and any suggestions they might have. Paul Delaney - K6HR paul.hamra...@verizon.net http://k6hr.dyndns.org:8080 ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
Re: [Flexradio] VU5K With Dual Band Yagi
Paul, I use separate antennas, but have found that setting the AGC-T properly is essential. If set too high, it will amplify the noise, and it wipes out the downlink. By backing off, per the instructions in the manual, RX works very well. If I found the correct antenna on the Gulf Alpha site, the antenna uses separate feeds. For mode-J, it is very common to get noise. You can try this filter. Depending on the rest of the station, the results can be dramatic. http://www.amsat.org/amsat-new/articles/Mode-J/ 73s, Alan WA4SCA Is anyone using a 5000/VU5K with a dualband yagi for satellite work with any positive results? I recently put up a Gulf Alpha EZ Sat Dualband Satellite Yagi and it the performance has been very disappointing. The Flex RX downlink is completely 'overwhelmed' during TX on the uplink. The RX panadapter shows a flat line and a 10-20db rise during uplink TX effectively making my downlink signal unusable in trying to find my signal on the transponder. Before I ditch this antenna, I'd like to hear from anyone using a dualband antenna for satellite work, and any suggestions they might have. Paul Delaney - K6HR paul.hamra...@verizon.net http://k6hr.dyndns.org:8080 ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
Re: [Flexradio] VU5K With Dual Band Yagi
Alan, thanks for this tip. I wasn't the original writer of this issue but will try it. When I do reduce power it gets rid of birdies and intermodal on the downlink but makes it very marginal to make contacts near the horizon. This should help. As a chance question, would simply hooking up the 2-meter port of a diplexer to a 2-meter RX side of my transceiver help eliminate 2-meter intermodal from public safety repeaters and cell-phone towers near my location? I'm thinking maybe the 2-meter side of a diplexer might have band pass or notch filter characteristics as well. I have severe birdies and intermodal from nearby RF sources on 2 meter weak signal work. Bob, NZ5A Sent from my iPhone On May 13, 2012, at 6:29 PM, Alan P. Biddle apbid...@united.net wrote: Paul, I use separate antennas, but have found that setting the AGC-T properly is essential. If set too high, it will amplify the noise, and it wipes out the downlink. By backing off, per the instructions in the manual, RX works very well. If I found the correct antenna on the Gulf Alpha site, the antenna uses separate feeds. For mode-J, it is very common to get noise. You can try this filter. Depending on the rest of the station, the results can be dramatic. http://www.amsat.org/amsat-new/articles/Mode-J/ 73s, Alan WA4SCA Is anyone using a 5000/VU5K with a dualband yagi for satellite work with any positive results? I recently put up a Gulf Alpha EZ Sat Dualband Satellite Yagi and it the performance has been very disappointing. The Flex RX downlink is completely 'overwhelmed' during TX on the uplink. The RX panadapter shows a flat line and a 10-20db rise during uplink TX effectively making my downlink signal unusable in trying to find my signal on the transponder. Before I ditch this antenna, I'd like to hear from anyone using a dualband antenna for satellite work, and any suggestions they might have. Paul Delaney - K6HR paul.hamra...@verizon.net http://k6hr.dyndns.org:8080 ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
Re: [Flexradio] VU5K With Dual Band Yagi
I have one of those and I've used it numerous times, including several times at Field Day, with my FT-847. The first time I used it in fixed elevation with the 15* bracket it comes with, and I was very disappointed. I then mounted it with my G-5400 Az-El rotor, and it made a tremendous improvement. The rotor is controlled using a Fox Delta ST-2 with SatPC32, which also controls the radio tuning. One thing you really should do is use a 70cm bandpass filter. I'm using a Comet diplexer, as described various places on the Net, along with a 2M bandpass filter on the output of the FT-847. *Anything* you can do to keep 3rd harmonic energy, or 2M fundamental energy, out of the 70cm side will greatly help with the desense problem. The diplexer is mounted ahead of the SSB Electronic preamp I have. Regardless of the radio and antenna you use, a good preamp makes a noticeable improvement, and is well worth the money. Good coax is important, too. All these things have been field proven by many satellite operators, and if you do them, you should have solid copy on the downlink. I have to admit I was one of those who thought they knew better about antennas, pointing, preamps, and such, and you know what? I didn't start to get good results with satellites until I had every one of these ideas implemented *ON THE GULF ALPHA ANTENNA*. Save yourself some grief, and get a diplexer, a preamp, and good coax BEFORE you junk the antenna. It's a good antenna, but is only one part of the system! PC control is nice, but you can manage the antennas manually, and programs to do Doppler correction _should_ be easy to implement with the Flex. I was planning on getting the V/U upgrade for my Flex 5000 until I saw the price. Since I already have a capable satellite radio, I passed on the V/U upgrade. 73, Jim KQ6EA On 05/13/2012 10:11 PM, Paul Delaney - K6HR wrote: Is anyone using a 5000/VU5K with a dualband yagi for satellite work with any positive results? I recently put up a Gulf Alpha EZ Sat Dualband Satellite Yagi and it the performance has been very disappointing. The Flex RX downlink is completely 'overwhelmed' during TX on the uplink. The RX panadapter shows a flat line and a 10-20db rise during uplink TX effectively making my downlink signal unusable in trying to find my signal on the transponder. Before I ditch this antenna, I'd like to hear from anyone using a dualband antenna for satellite work, and any suggestions they might have. Paul Delaney - K6HR paul.hamra...@verizon.net http://k6hr.dyndns.org:8080 ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
