February 2008 - AMSAT-BB - mailman.amsat.org

antenna attenuation
by w7lrd＠comcast.net 01 Feb '08

01 Feb '08

Hello Has anyone encountered this situation- My satellite antennas are about 15 feet off the ground. approximatly 18 feet away at that height is the base of a 25 foot tripod that holds my HF quad. When aiming at a certain direction about 15-20 degrees I can't seem to get through to AO-7. I am trying to connect with OH8MBN. Other directions I can usually hear my downlink almost down to the horizon. On 70cm I run about 80-100 watts to a 40 el cp yagi. I can pick up my down link when the sat is about 7 degrees. 73 Bob W7LRD Seattle -- "if this were easy, everyone would be doing it"

2 1

Re: Satellite tracking programming ideas
by phillor＠telstra.com 01 Feb '08

01 Feb '08

> SatPC32 works similar as Instant Tune (see Anthony Monteiro's detailed > answer): Thank you Anthony and Erich for your replies. I'm always impressed by the generosity of this list's members. During the past week I've spent hours debugging my code because it was originally supposed to work the way that you have both described. Actually it did, or at least I thought it did, but that was before I bought a laptop computer and a USB to serial converter. The code has been updated many times during the past eight years and during one of those updates I changed the user interface so that the user had to stop the tracking during manual tuning; effective but clumsy. Reading the FT-847's receiver frequency originally caused me some frustration. I had included a delay after each read and write command because the FT-847 doesn't return a command acknowledgement. While writing this reply I realised that instead of a delay I shroud be waiting for the serial port to receive five bytes from the radio. This has turned out to be more reliable but I still get occasional read errors and I feel that it's due to the USB to serial converter. When an incorrect frequency value is read, at one second intervals, the same value is reread from the serial port buffer each second until the tuning knob is moved again. Maybe the read command is working correctly and instead it's the write command that instructs the radio to output it's frequency that's not working reliably. I remember reading about some sort of delay that the FT-847 requires but I cannot remember what it was all about. It could be important. A lecturer once told a class that I attended that explaining a problem to anyone, even your dog if no one else will listen, often leads to an answer. It's helping in this instance, but not enough to lead me to the final answer. To add to my frustration, my ISP has made changes to their mail server which now prevents me replying to any e-mails that are outside of their domain. I have a workaround but it's a real pain. Thank you Wayne for your thoughts on frequency drift. I spent many hours listening to AO40's beacon and did manage, eventually, to get the drift under control. -- Regards, Phil.

4 4

SatPC32 wont stay in UTC mode
by Charles Reiche 31 Jan '08

31 Jan '08

Anyone know of a way to get SatPC32 to stay in UTC mode every time on startup. There is a setup checkbox to "turn on" the time feature on startup but I dont find that it acts any differently whether or not I have the program in UTC or Local when setting this option or when starting up or closing down the program. Thanks Charlie N3CRT

1 0

ISS Repeater turned on
by Tony 31 Jan '08

31 Jan '08

All, The ISS repeater was on during the last pass - orbit #52688. Uplink - 437.800FM Downlink - 145.800FM Tony -K2MO

2 1

Re: antenna attenuation
by Dave Guimont 31 Jan '08

31 Jan '08

> >Has anyone encountered this situation- My >satellite antennas are about 15 feet off the >ground. approximatly 18 feet away at that >height is the base of a 25 foot tripod that >holds my HF quad. When aiming at a certain >direction about 15-20 degrees I can't seem to >get through to AO-7. I am trying to connect >with OH8MBN. Other directions I can usually >hear my downlink almost down to the horizon. On >70cm I run about 80-100 watts to a 40 el cp >yagi. I can pick up my down link when the sat is about 7 degrees. Bob, Be wary of AO7! It is my old standby, and I do a lot of listening...In attempt to determine a pattern, but my efforts have been fruitless.. Today, 1feb08z, I chased the band and NOTHING until about 30°, then the sigs were erratic...made two contacts... Sometimes it is loud and clear AOS to LOS... Not suggesting that is YOUR problem, but be wary, my friend....And I have nothing but sky from horizon to horizon...with my sat antennas.... 73, Dave, WB6LLO dguimon1(a)san.rr.com Disagree: I learn.... Pulling for P3E...

1 0

RFI source found - sort of
by Tony 31 Jan '08

31 Jan '08

All, I was able to track down the general location of an RFI problem I've been hearing since December. It's in the vicinity of 3 new homes on a cul-de-sac not far from my QTH. I'm told the pulse noise sounds like the RFI from an invisible electric fence. At this point, it's hard to tell which home it's coming from with the HF mobile because the signal strength is overwhelming at the location. I'll have to get up close with a portable AM radio; I'll probably need some shielding around it. Wish I knew exactly what the noise was; I'd hate to 'accuse' a neighbor of causing RFI and have it turn out to be the power company. I have a recording if anyone is interested. The question is, what to do in the worse case scenerio if the home owner decides not to take action to remedy the problem? Anyone on the reflector been through this before? Apologies for the off-topic note -Please reply direct... Tony -K2MO

3 2

Trade Compaq server for radio!
by chad phillips 31 Jan '08

31 Jan '08

As you may have seen in my last post, I am looking to purchase a handheld or rig similar to a Tr-751a to get me back on the air. I have a Compaq DL-360 server that I plan on posting on ebay this weekend. However if there is someone on this list that is interested in trading for it, I would be happy to consider it. Either email me for the specs if you are interested or I will post them tonight later. Thanks again, Chad kg0mw

1 0

Which handheld for sats?
by chad phillips 31 Jan '08

31 Jan '08

I don't want to open up a can of worms, just looking for your advice....... I have been off the birds for a few years and am wanting to get back on next month. Because funds are somewhat limited, I am considering every possible combination of radio(s) for getting back on the air. One option is to purchase a handheld that I can use with an Arrow antenna. I would like to know which handheld do you use or which handheld is "the best" for sats. It must be full duplex. Thanks in advance! Chad kg0mw en-13 Sioux Falls, SD kg0mw.blogspot.com

1 0