Hi Roger,

Thanks very much for the reply. I did forget to mention that I will be using my Kenwood TS2000 for this purpose. This allows me the full 0-100 watts choice for 2m, and 0-50 watts choice for 70cm. The preamps are only for receive. The RF switches are between the rig and the preamps and will bypass the preamps upon transmit. I can start out my RF out anywhere within the above stated ranges.

Any further thoughts?

.paul

Roger Kolakowski wrote:

...

My initial investment is minimal

...

When I assemble the RF switches I must choose a RF range....The range is determined by the choice of a specific resistor. The default three >ranges suggested are 0-10 watts, 10-30 watts, and 30-100 watts.

The answer is actually in what transmitters or power amplifiers are you planning to use that fit within your budget?

Watts cost money...

With a limited gain omnidirectional you might best aim toward the middle range but if you are looking at used SSB/CW equipment at 430, many of the less expensive older radios only ran 10 watts out. Of course a "Linear Amplifier" for SSB/CW could move you up but is not necessarily inexpensive.

You might want to just accept the fact that you may need to "climb the tower" again once you settle on your transmitters.

Roger WA1KAT

Sent: Sunday, October 19, 2008 1:30 AM Subject: [amsat-bb] beginner question re: uplink power

...

hello,

My initial investment is minimal

When I assemble the RF switches I must choose a RF range....The range is determined by the

...

choice of a specific resistor. The default three ranges suggested are 0-10 watts, 10-30 watts, and 30-100 watts.

I think I would contact Ramsey and see what the resistor selection limitations are, unless you have a schematic and can determine it from the design.

Sure enough, if you set it for 10 watts you are going to, some day, put 50 or 100 watts through it in error and I'm assuming if you kill the remote switching it defaults to receive and therefore doesn't switch the preamp out resulting in a trip up the tower to fix 2 things.

If you set it for 100 watts, you will someday want to run less and again it won't key. Same trip up the tower.

Hard wiring, as has been suggested, is your safest choice. As the switch has the relay in it, maybe Ramsey can tell you where to tap in to directly switch the sensor.

Nice choice of rig though ;-)

Roger WA1KAT

----- Original Message ----- From: "corner5" [email protected] To: "Roger Kolakowski" [email protected] Cc: [email protected] Sent: Sunday, October 19, 2008 1:42 PM Subject: [amsat-bb] Re: beginner question re: uplink power

Hi Roger,

Thanks very much for the reply. I did forget to mention that I will be using my Kenwood TS2000 for this purpose. This allows me the full 0-100 watts choice for 2m, and 0-50 watts choice for 70cm. The preamps are only for receive. The RF switches are between the rig and the preamps and will bypass the preamps upon transmit. I can start out my RF out anywhere within the above stated ranges.

Any further thoughts?

.paul

Paul and all,

I would be curious to hear from anyone currently using verticals with preamps as their primary receive antennas. I have hesitated to respond to your initial post, Paul, because (1) I am very new to the satellites; (2) as a result, my personal experience with antennas involves only the Arrow handheld antenna, the eFactor 0-gain omni antenna, the Elk dual-band log periodic an MFJ mag-mount dual-band vertical for my vehicle, and HT-specific antennas (Pryme AL800, MFJ 1715 and 1717, etc.); and (3) my other knowledge regarding using omni antennas for satellite work is limited to what I have read here and elsewhere on the Internet.

All of that being said, I believe I would opt for something other than a vertical - even with preamps - as my prime base-station antennas for the satellies. I haven't yet built one of the Ramsey preamps, but I intend to as the weather turns cool here in North Georgia and I spend more time inside. I am curious about its ability to improve reception for me with the sFactor, which is an outstanding transmit antenna for reaching the satellites - based on my experiences with it. I also logged more than a dozen contacts involving AO-27, AO-51 and SO-50 using the eFactor with an HT as a handheld antenna. My personal experience suggests that a preamp would help it on the UHF receive side a great deal, although it honestly exceeded my expectations - given the physical size of the UHF part of the antenna.

The N3TL handheld station has worked 46 states, VE1-2-3-4-5-6-8-9, Mexico, Venezuela, Barbados and marimtime mobile stations all on 5 watts' rf out or less. It also has worked 20 states, Ontario, Mexico and Venezuela on .05-watt (50 milliwatts) on the same set of 2 AA Duracell batteries. For the sake of perspective, I made my first-ever satellite contact on June 28th of this year - less than 4 months ago.

From here, output power isn't the issue. I believe your money and time will be best-invested in optimizing the receive side of your satellite station.

Best of luck with it, and 73,

Tim - N3TL AMSAT Member No. 36820 Athens, Ga. - EM84ha -------------- Original message from Edward Cole [email protected]: --------------

At 09:30 PM 10/18/2008, 12.01 wrote:

...

hello,

I have a beginner question. I am in the process of setting up my first satellite station. My initial investment is minimal and I have chosen to start out with a pair of 2m and 70cm omni antennas on the roof. To help out a bit I am also adding a mast mount preamp on each antenna. To protect the preamps they will be switched out of line by a RF sense switch (one for each amp). For reference the two preamps and the pair of RF switches are all made by Ramsey (I know there are better preamps, but not available in my current budget). I am keeping this initial adventure limited to the LEOs (and ISS, etc.).

_The question: _ When I assemble the RF switches I must choose a RF range for the switch to work within. The range is determined by the choice of a specific resistor. The default three ranges suggested are 0-10 watts, 10-30 watts, and 30-100 watts. I would be able to change the range later but it would require removing the unit from the mast.

So... not having any experience (yet),_ what uplink power range is recommend for non-gain antennas?_ Is there one range that should cover the LEOs? If not, how much should I expect the required uplink power needs to vary across various satellites? Is it different for each band? I have read that it is always best to never be louder than the beacon and that's fine. I'm just needing to know where to start off my hardware choices.

Thanks in advance for any help from you folks with the know-how. I look forward to a qso with you.

.paul ac0z _______________________________________________ Sent via [email protected]. 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

I'm surprised that you have had only one reply. I am not QRV on the Leos so my advise is not as good as what you might get. My "understanding" is that one can work most of the Leos with power <10w. This is IF the stations on the bird also comply by not using more power than is needed. If a "power war" ensues to try to capture the satellite then running low power may be less effective to "break in".

But seeing that so many folks run HT's that typically are 5w, I think you might chose the lowest range as long as your equipment output matches. You have to consider that you will have no antenna gain using omni-directional antennas so uplink RF power needs are affected, accordingly. NOW if some experienced sat op will add their input on this subject you should have the info you need.

I wonder if the Ramsey preamps allow for "hard" switching. That is by separate control line that the radio PTT controls. Then You have no issue with RF power and would run the units with the RF sense disabled. I should state that "many" (dare I say most) experienced VHFers that run high power (>100w) use hard-wired switching. I know of NO eme stations that use RF sense control lines.

PS: when my standard AO-10/13/40 ground station is re-installed I will have available 5-60w with 16.5 dBc UHF uplink (all-mode).

---

73, Ed - KL7UW BP40iq, 6m - 3cm 144-EME: FT-847, mgf-1801, 4x-xp20, 185w 1296-EME: DEMI-Xvtr, 0.30 dBNF, 4.9m dish, 60W http://www.kl7uw.com AK VHF-Up Group NA Rep. for DUBUS: [email protected]

---

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Sent via [email protected]. 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

Unfortunately AO-51 seems to be plagued by the same cretins that jam repeaters with silly noises and bursts of music at certain times. Even when they're not doing that there's always someone trying to run 2.5kW into a massive stacked antenna. I've noticed that these are also the ones that sit there calling "CEEEE KYOOOOOOOOOOOOOOO CEEEEEEEEEEE KYOOOOOOO CEEEEEEEEEEEE KYOOOOOOOOOOOOOOOOOO <whistle whistle whistle> CEEEEEEEEEE KYOOOOOOOOOO CEEEEEEEEEEE KYOOOOOOOOOOOOO CEEEEEEEEEEEEE KYUUUUUUU" for nearly the whole damn pass without pausing for breath.

This fact was anticipated by interested AMSAT members many years prior to the launch of AO51, with respect to 2-user FM voice. It was voiced at several conventions that I attended, and some of us were told by some of the "powers that were" that is was "none of our business"!! At that time some of us had only one vote each!!

73, Dave, WB6LLO [email protected]

Disagree: I learn....

Pulling for P3E...

At 05:01 AM 10/22/2008, Ben Jackson wrote:

While this is an issue, it is often overblown (at least in the US). I think the solution involves education and outreach. When someone like this is one of the Easy Sats, I grin an bear it and then look them up on QRZ for an e-mail address. I send them a Hi-Ho, tell them they made it

I agree. Many newcomers don't know how to operate on sats, and this is often compounded by poor receive performance on many beginners' stations. On many occasions, if an offending station was within simplex range, I'd call them aside after the pass, and have a bit of a chat. If there was another pass to follow, I'd invite them to have another go, focusing on receiving the downlink, and if they do hear the bird, giving a quick call and try their luck. In the downtime between or after passes, we'd talk about things like improving downlink reception. One year, while holidaying in Queensland, I had a whole bunch of locals using UO-14 with portable gear, after talking them through the process on the local repeater before the passes. :) If people have a HT, I will suggest they take it outside during a pass and have a listen, if they don't have any suitable antennas already setup.

Almost everyone I have spoken to has gone on to make a successful satellite contact, after this bit of Elmering.

in, and point them in the right direction for proper operation. If someone is a repeat offender, sadly the only way to deal with them is try not to talk to them and hope they get bored.

That's about all you can do...

<shameless_plug> I addressed most of these concerns in my "The Courteous Ham's Guide to AO-51" paper that I wrote in March. You can check it out at: http://www.innismir.net/article/26 </shameless_plug>

Cool. I wrote a similar piece around 8 years ago called "satiquette", which addressed these issues on FM birds. At the time, SO-35 was active, and that was hugely popular down here. It was a lot of fun. :) I also wrote some articles on using SO-35's parrot mode, which took a lot of skill to get any useable throughput. The parrot (for those who don't know or recall) was basically a simplex store and forward repeater that worked in the following cycles: <single tone> 10 second uplink slot (satellite receiving) <double tones> 10 second downlink slot (satellite transmitting). As one could imagine, this had _massive_ hidden station issues, but if you did it right, you could get a QSO. Just enough time to get a callsign and RST, with time for one or two others to do the same in the slot. :)

As a community, the first step for fixing these problems on satellites should be outreach and education. More people getting into satellites is a good thing and we should be encouraging it. If people aren't "behaving" we should be the first people to offer a helping hand.

Agree. The majority of "anti-social" behaviour is actually ignorance, and education goes a long way to making things work smoothly. :)

73 de VK3JED http://vkradio.com