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CX2SA > SATDIG 16.03.10 21:17l 892 Lines 32604 Bytes #999 (0) @ WW
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To : SATDIG@WW
Today's Topics:
1. Digital HAMSAT Centers (Trevor .)
2. Call for Papers--2010 ARRL/TAPR Digital Communications
Conference (Ford, Steve, WB8IMY)
3. EL89, EM70, maybe EM80 (Andrew Glasbrenner)
4. ND9M Road Trip - Final (claryco@xxx.xxxx
5. fun with preamps (Bob- W7LRD)
6. Re: fun with preamps (Stan, W1LE)
7. Re: fun with preamps (i8cvs)
8. Re: fun with preamps (David - KG4ZLB)
9. K4T (Mike)
10. Re: fun with preamps (n1jez@xxxxxxxxxxxxxxxxx.xxxx
11. Re: K4T (Mark Hammond N8MH)
12. K4T wind turbine (Mike)
----------------------------------------------------------------------
Message: 1
Date: Mon, 15 Mar 2010 19:36:38 +0000 (GMT)
From: "Trevor ." <m5aka@xxxxx.xx.xx>
Subject: [amsat-bb] Digital HAMSAT Centers
To: amsat-bb@xxxxx.xxx
Message-ID: <389916.23655.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=utf-8
The Times of India newspaper:
OLKATA: If conventional communication networks fail when nature unleashes
her fury in the form of Aila-like cyclones, extensive floods and
earthquakes, governments can execute rescue and relief operations through
satellite-based low-cost HAM radios.
Article at
http://timesofindia.indiatimes.com/city/kolkata-/Disaster-management-2-HAM-rad
io-units-in-state/articleshow/5681180.cms
73 Trevor M5AKA
Daily Amateur Radio Email/RSS News: http://www.southgatearc.org/
Email Your News To: editor at southgatearc.org
Or Upload Using Form At: http://www.southgatearc.org/news/your_news_1.htm
----
------------------------------
Message: 2
Date: Mon, 15 Mar 2010 15:38:48 -0400
From: "Ford, Steve, WB8IMY" <sford@xxxx.xxx>
Subject: [amsat-bb] Call for Papers--2010 ARRL/TAPR Digital
Communications Conference
To: "RTTY Reflector" <rtty@xxxxxxxxxx.xxx>, <amsat-bb@xxxxx.xxx>,
<vhf@xxxx.xxxxxxxx.xxx>, <psk31@xxxxxxx.xx.xxx.xx>,
<digitalradio@xxxxxxxxxxx.xxx>
Message-ID:
<145372871023544E98881538F29B1DFC0F7C68@xxxxxxxx.xxxxxx.xxx>
Content-Type: text/plain; charset="us-ascii"
Technical papers are solicited for presentation at the 29th Annual ARRL
and TAPR Digital Communications Conference to be held September 24-26,
2010 in Portland, Oregon. These papers will also be published in the
Conference Proceedings (you do NOT need to attend the conference to have
your paper included in the Proceedings). The submission deadline is July
31, 2010. Please send papers to:
Maty Weinberg
ARRL
225 Main St
Newington, CT 06111
or you can make your submission via e-mail to: maty@xxxx.xxx
Papers will be published exactly as submitted and authors will retain
all rights.
73 . . . Steve, WB8IMY
ARRL
------------------------------
Message: 3
Date: Mon, 15 Mar 2010 15:58:00 -0400
From: Andrew Glasbrenner <glasbrenner@xxxxxxxxxx.xxx>
Subject: [amsat-bb] EL89, EM70, maybe EM80
To: Amsat-BB <amsat-bb@xxxxx.xxx>
Message-ID: <4B9E9148.6030703@xxxxxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I'm headed north tomorrow for work, and will likely be on from these
grids at some point on some satellite. If you need any of these, drop me
a note today and I'll call or listen for you.
73, Drew KO4MA
------------------------------
Message: 4
Date: Mon, 15 Mar 2010 17:34:39 -0400
From: claryco@xxx.xxx
Subject: [amsat-bb] ND9M Road Trip - Final
To: amsat-bb@xxxxx.xxx
Cc: cori1956@xxx.xxx
Message-ID: <8CC929E736B0F8C-2928-2926@xxxxxxxxxxxx.xxxxxx.xxx.xxx>
Content-Type: text/plain; charset="us-ascii"
Thanks!
Cori and I arrived at home this past Wednesday and found everything at home
in good order. (That doesn't include having so much mail waiting for us at
the post office that we overloaded up a hand truck to get it to the car!)
Thanks to everyone we worked during our road trip and especailly to the AO51
Operations and Command Teams for their support throughout!
Cori drove most of the time while I navigated. She's not a ham, but she's
been with me on a lot of ham radio related trips. I really appreciated her
willingness not only to meet every satellite pass, but also to move the
vehicle back and forth to nail down the exact GPS coords for a grid line.
After I climbed back into the car after many of the passes, her first
response was "when's the next pass?" That's what makes a successful road trip!
Thanks also go to everyone who provided information along the way,
especially to WA4NVM, K8YSE, WB3JFS, and WB3JFS for the regular updates by
phone and e-mail throughout the trip.
QSL Info.
Pse send me an e-mail off list indicating the grid squares you need
confirmed. QSO data is helpful but won't be needed as I'll simply do a
search on the Excel log and find the contacts. I'll mail the QSLs to you at
the address on your QRZ.com page; if your mailing address is different, pse
advise accordingly.
QSLs are very welcome and appreciated but not necessary. Also there's no
need to send an SASE or postage.
Numbers.
For those who like 'em, here are a few to summarize the trip.
Driveway to driveway, we drove 10,022 miles through 13 states during the
seven weeks we were "out there". The planned route included operating from
85 different grid squares; we made it to all 85 of the originally scheduled
grids plus two more for a total of 87 or 18% of the grids in the continental
US.
In all, 1076 contacts were made during 92 passes. Of those passes, 51 were
from two-grid lines and one more from a four-grid point.
A total of 177 different stations were worked. Of those, 44 worked me in 10
or more grids. K8YSE led the pack by working me in 78 of the 87 grids!
WA4NVM was next with 64 grids, and KB0RZD, N5UXT, and WA5KBH with 50 or more!
Trip updates were sent regularly to the AMSAT-BB as well as to my
distribution list containing more than 70 e-mail addresses. Hopefully the 20
or so updates were enough to keep everyone informed and interested but not
feeling inundated.
Two grids were the main focus for this trip: DL88 and El15. For the 6M
buffs, DL88 is on the Most Wanted List for the 6M world. I had 6M with me -
tks to WA4NVM for providing the antenna! - but unfortunately there were no
band openings while we were there. EL15 at Brownsville, Texas, isn't hard to
get to; there's just not much activity from there.
Using simple rounding, a grid square measures 60 miles by 120 miles which
comes up to an area of 7200 square miles. Multiply that area by 87 different
grids and Cori and I were able to operate from enough territory representing
more than 600,000 square miles. That's a lot of turf!
(K8YSE plotted all the grids we covered on a GCMwin graphic and made it
available on his web server. The address is "www.papays.com/nd9m.jpg"; check
it out if you haven't already.)
We would have loved to have spent a full day or more operating from each
grid square to maximize the availability, but that wasn't possible. Still,
several grids were available during multiple passes.
DL88 came in first with being on during 9 passes during which 98 contacts
were made. Second was DM72 at 6 passes and 59 contacts. The EL15/EL16 grid
line was on for 5 passes that netted 37 contacts. Grids DM82, EL07, and EL08
were on four times; eight grids were on during three passes, and 14 others
were on twice.
Equipment.
The gear used for this trip included an FT-897D for TX, and an FT-817ND was
velcroed to the top of the 897 and did the RX work. An Arrow-2 was the
antenna for all contacts.
But we were on guard for Murphy's Law, so I had a spare FT-817ND still in
the box as a back up, plus just in case the Law really kicked in, I brought
my trusty TH-F6A HT. An Elk antenna rode shotgun for the duration, but it
never came out of the trunk until we got home.
I took out the Arrow's diplexer and fed the antenna with separate RG-58
coaxes. Before the purists scream about how lossy 58 cable is, the length of
each cable was about 10 feet; the loss tables show that even at 70cm, that
length would cost me
a bit more than a dB of signal.
Certainly that's nothing to disregard, but the flexibility of RG58 easily
made up for the loss. Also less lossy cable types like RG-8, -213, and 9913
would still have introduced about a quarter to a half dB of loss themselves,
so the benefit of using it really wasn't justifiable.
A bag of silver teflon connectors, a 100-foot roll of spare coax, a butane
soldering gun (with a can of refill gas), a couple rolls of wire, lots of
spade connectors of both genders, a toolbox, and a portable table vice were
among the back up supplies.
Surprisingly, one of the most valuable accessories turned out to be a small
portion of common kitchen shelf lining. Nearly all of my operating was done
with the station set up on the hood of the SUV. The FT897D had its own
rubber lining on its rail stand, but other things such as the laptop, GPS,
digital recorder, headphones and other items often slid around on the
sloping hood. The shelf lining was cheap as dirt and did the trick
wonderfully.
Hardware Failures.
As with any lengthy project, there will be equipment issues. This trip was
no different.
The first 817 failed at Big Bend; it simply didn't power up at the start of
a pass. It's under warranty and will be off to Yaesu this week.
The original Arrow-2 had a hard day near the end of the trip when I was
loading the SUV as we prepared to leave town and forgot that I'd put the
antenna on top of the car's roof. I saw a glint of reflected sunlight in the
rear view mirror as we joined the interstate traffic in Dallas.
We stopped quickly, but by the time the antenna had been retrieved, it had
been run over by two vehicles. The boom was bent somewhat and several of the
70cm elements were made of hollow aluminum arrow stock - hence the name
"Arrow" - and were easily crushed. (I take off the 2M elements and store
them separately inside a door well.)
But as you know, crushed metal is still metal, and the elements performed as
they should for the rest of the trip; they just weren't nice and pretty!
Most of the EL15/EL16 operating was done at a highway interchange that was
being constructed in Brownsville. The day before had been warm and sunny;
this particular day was 30 degrees or more colder, overcast, and windy.
Several ops commented on the air that they heard the wind howling across my
microphone. What they didn't see was me leaning several degrees into the
wind and still controlling the antenna!
Did you know that an Acer Aspire One netbook will fly 30 feet if the right
gust of wind catches it? I didn't, but I sure do now...
The most embarrassing thing to occur during the trip was caused by Operator
Headspace Syndrome. I was sitting in the motel room near Denver and knocked
a nearly full commuter cup (top heavy by design) of coffee on to my laptop;
most of the contents spilled directly onto the keyboard.
The laptop worked fine after my stepson (whom we were visiting and has an IT
service company nearby) performed emergency surgery on it. Everything had
already been backed up, so it was just my pride that was in jeopardy.
Weather.
Although January and February are not the best months to plan outdoor
activities in states know for heavy snow, we were very fortunate to have
sensational weather for nearly the entire trip. A bit of snow here, some
wind there, and a few frozen fingers to keep me wondering about the overall
purpose, but overall we had very good luck.
We were faced with the likely prospect of a borderline blizzard in Dodge
City, Kansas. We did the usual tourist type stuff, but when the snow started
falling and had already been predicted to be upwards of a foot, we really
did have to "get the hell out of Dodge"...
Later on in the trip, we "met" a new, if snowy, friend just after I operated
from the DM86/DM87 line in southeastern Colorado. Now if only our friend,
Gridley Square, would get his license...
Big Bend / DL88.
The majority of DL88 is located within Mexico. Since I don't have an XE
recip permit, my only choice was to get to the very small sliver of the grid
that's inside the US.
That sliver lies within Big Bend National Park, which is mostly desert with
very few roads. One of those roads, Talley Road, conveniently
runs south across the 29-degree latitude into DL88. The only problem is that
all roads in that part of the park require four-wheel drive vehicles, and in
most cases high clearance is necessary as well.
We discussed our plans with park authorities several times and were assured
that there would be numerous ridges and gullies caused by previous flooding
to deal with but that as long as we were careful while enroute, we would
have no significant problems getting to our campsite. We took the shortest
path, Black Gap Road, and were soon dealing with the road conditions as
described.
But one spot that surprised us was a section of the road that forced us to
climb a two-foot high mini-cliff. Someone who'd been there before us had
moved a lot of rocks to make a rock ramp. The ramp wouldn't get us over this
thing, so I had to move a lot more to rebuild it. While I acted as a road
spotter, Cori got the SUV up and over that cliff, but it was a huge challenge.
The drive from the park office to our campsite was about 25 miles; the Black
Gap Road portion was only 8 miles but took four hours to drive! (Our SUV's
undercarriage took a major beating, and the muffler looks like a baseball
bat went to town on it, but otherwise there was no sustained damage.)
A few days later when it was time to leave, we decided to take River Road
back even though it was more than 10 miles longer than Black Gap Road; our
feeling was that it really couldn't be much worse. As it turned out, River
Road was a breeze in comparison; there were still lots of wash outs and
gullies, but no cliffs. Even with the additional mileage, we made our escape
in a bit more than two hours, and that includes taking care of a flat tire!
When we got back to the registration office a few days later, we were told
that taking Black Gap Road was definitely not advised and that another less
brutal road is recommended; we would have appreciated getting that info
before we ventured out.
Nasty road conditions and ham radio aside, this stay was incredibly quiet
and relaxing. There were no other people or cars; the only critters we saw
for several days were a couple hawks and a road runner. There was also no no
cell signal, electricity, or water. We had to bring in all supplies, but we
had everything we needed.
By the way, as an indication of just how far out we were when camping in
DL88, no park rangers drove out to patrol; they sent a surveillance plane to
verify that we'd survived our trip and arrived at our campsite!
If you want to go somewhere out of the way, this is a great place to
consider. But if you come out there, don't forget your shovel...
Grid Lines vs State Lines.
One of the many interesting things learned during the trip was that all
state lines are not created equal. Looking at a grid line map, a number of
grid lines appear to run concurrently with state lines.
For example, part of the Texas / Oklahoma line looks to be at the 100-degree
west longitude line, which separates the DM and EM fields. We followed
Oklahoma State Route 9 to the state line that was marked with a cement
cornerstone alongside the road.
My Garmin 60CSX GPS showed that the state line was actually at 100-00.025W
or about 125 feet west of the DM94 / EM04 line. (The GPS was indicating +/-
11 feet accuracy at the time.)
Our theory was that when the state lines were surveyed, they were identified
using equipment that was state of the art at the time but hardly with the
accuracy of GPS. Adjusting state lines (and probably municipal and county as
well for that matter) much later after the fact would not only serve no
productive or beneficial purpose and only rack up enormous costs.
>From then on, we were no longer surprised to see state and grid lines look
to be the same in the atlas but then find them to be as much as a couple
miles apart. Since more than half of my operations were from grid lines, the
GPS was used every time to decide the location of the gear.
Arrow Factory.
Since we were in the Cheyenne area, we stopped off at the Arrow shop. The
owners, Matt (N0IMW) and Dot (N0JFW), gave us a great tour of the facility.
We spent most of the afternoon being shown every detail of how they turn all
the stock materials into the various antennas they make.
A lot of the equipment used is commonly found at Home Depot or Lowes but We
were surprised to learn that Matt fabricated many of the modifications to
make a simple power drill or something else into production line assembly
items. He interfaced programmable logic controllers (PLCs) to effect
precision cuts and hole boring. He's also replacing many of the motor-driven
tools with pneumatic systems using his own designs.
Dot is the primary worker bee in the shop, and she clearly takes pride in
the job she does. While we were there, she saw the Arrow-2 antenna that I'd
been using, shook her head when she saw how battle tested it was, and
refurbished it on the spot.
And while we there, I operated an AO27 pass from outside their shop door.
The building is all steel, which would have blocked the satellite's signal,
but fortunately the bird's path cleared the building easily.
It was a fascinating visit, and Cori and I enjoyed every minute.
Houston.
As the trip was winding down, I got word that the Greater Houston Hamfest
was to be held a couple days later. We were a little behind schedule, a
couple hundred miles away, and going another direction, but when I mentioned
to Cori that there would be an AMSAT presence there, she said "let's go!"
It was a welcome opportunity to meet so many of the sat ops from the Houston
area and especially fun to help out as a receiving station during the W5H
satellite demos during the 'fest.
Wrap Up.
There were many, many other events and things that went on during the seven
weeks on the road, but these that I've described will have to suffice. Tks
again for all the contacts and support.
Now to the QSLs!
73,
Jim, ND9M / VQ9JC
Panama City Beach, FL / Em70
------------------------------
Message: 5
Date: Mon, 15 Mar 2010 23:28:07 +0000 (UTC)
From: Bob- W7LRD <w7lrd@xxxxxxx.xxx>
Subject: [amsat-bb] fun with preamps
To: amsat-bb@xxxxx.xxx
Message-ID:
<607411373.14767321268695687235.JavaMail.root@xxxxxxx.xxxxxxxxxx.xx.xxxx.xxxxx
xx.xxx>
Content-Type: text/plain; charset=utf-8
Hello
Just installed a AG-25 (Icom preamp)?on my 2M cp yagi.? No preamp noise
Smeter=0, preamp on Smeter=7.? Signals "appear" better after backing down
the volume with the preamp.? I have 8-10 feet of LMR400uf from antenna to
preamp, 50 feet of LMR400 to shack.? I suppose I was expecting more
"dramatic" results, I realize the AG-25 isn't the greatest and best, but it
works well with the 910.? Are these real world results for what I have.? S7
noise level seems a bit high.
as always-thanks
73 Bob W7LRD
------------------------------
Message: 6
Date: Mon, 15 Mar 2010 20:02:54 -0400
From: "Stan, W1LE" <stanw1le@xxxxxxx.xxx>
Subject: [amsat-bb] Re: fun with preamps
To: Bob- W7LRD <w7lrd@xxxxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <4B9ECAAE.10200@xxxxxxx.xxx>
Content-Type: text/plain; charset=UTF-8; format=flowed
Hello Bob,
Does the preamplifier have a internal gain control ?
If it does, back it off at ~ 6 S units.
Excess gain only reduces the system dynamic range.
The real test is with a SINAD meter or a NF meter, injecting a test
signal up at the preamplifier input,
and reducing gain until NF or SINAD sensitivity is just barely degraded.
That will be the point of best S/N, (best sensitivity).
Most of the S7 reading you have is just noise, not signal.
The preamplifier could be defective and performance is out of spec.
Whatever that spec is, I do not recall ever seeing a ICOM AG-25/35
performance spec.
If the preamplifier is a multi stage unit, the first stage which sets
the system noise figure
could be defective/soft and the second stage just amplifies the noise
ahead of it.
Most convincing would be a NF test with professional meter.
Send it to me and I will test for free. I will NOT repair. I will NOT
open it.
Include return postage if you want it returned (HI).
I will provide you a plot of the NF and gain performance using
a HP-8970B Noise Figure Meter and HP-346C Noise source.
Of course, this offer is open to any other AMSAT member.
E-mail me for details.
What do you say ?
Stan, W1LE Cape Cod FN41sr
Bob- W7LRD wrote:
> Hello
>
> Just installed a AG-25 (Icom preamp) on my 2M cp yagi. No preamp noise
Smeter=0, preamp on Smeter=7. Signals "appear" better after backing down
the volume with the preamp. I have 8-10 feet of LMR400uf from antenna to
preamp, 50 feet of LMR400 to shack. I suppose I was expecting more
"dramatic" results, I realize the AG-25 isn't the greatest and best, but it
works well with the 910. Are these real world results for what I have. S7
noise level seems a bit high.
>
> as always-thanks
>
> 73 Bob W7LRD
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. 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
>
------------------------------
Message: 7
Date: Tue, 16 Mar 2010 01:31:31 +0100
From: "i8cvs" <domenico.i8cvs@xxx.xx>
Subject: [amsat-bb] Re: fun with preamps
To: "Bob- W7LRD" <w7lrd@xxxxxxx.xxx>, "AMSAT-BB" <amsat-bb@xxxxx.xxx>
Message-ID: <001701cac4a0$069dd960$0201a8c0@xxx.xx>
Content-Type: text/plain; charset="utf-8"
----- Original Message -----
From: "Bob- W7LRD" <w7lrd@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Sent: Tuesday, March 16, 2010 12:28 AM
Subject: [amsat-bb] fun with preamps
>
>
> Hello
>
> Just installed a AG-25 (Icom preamp) on my 2M cp yagi. No preamp noise
Smeter=0, preamp on Smeter=7. Signals "appear" better after backing down the
volume with the preamp. I have 8-10 feet of LMR400uf from antenna to preamp,
50 feet of LMR400 to shack. I suppose I was expecting more "dramatic"
results, I realize the AG-25 isn't the greatest and best, but it works well
with the 910. Are these real world results for what I have. S7 noise level
seems a bit high.
>
> as always-thanks
>
> 73 Bob W7LRD
>
Hi Bob, W7LRD
No preamp noise Smeter=0, preamp on Smeter=7 means very small. Step 1
without preamplifier tune your receiver in SSB or CW on a very weak carrier
like a beacon and rotate your antenna into a null until you can barely hear
a bit at about 1000 Hz over the noise. Step 2 now connect your preamplifier
and see by hears if the Signal to Noise ratio S/N improves or not. If you
can hear better the 1000 Hz bit your preamplier is useful othervise S meter
= 7 means only or mostly the amplified preamplifier noise.
Your test can be more accurate if instead to use your hears you connect an
analog AC voltmeter at the audio output of your receiver.More is the swing
of the AC voltmeter and better is the preamplifier i.e. lover is it's Noise
Figure.
Have fun.
73" de
i8CVS Domenico
------------------------------
Message: 8
Date: Mon, 15 Mar 2010 21:10:35 -0400
From: David - KG4ZLB <kg4zlb@xxxxxxxxxx.xxx>
Subject: [amsat-bb] Re: fun with preamps
To: amsat-bb@xxxxx.xxx
Message-ID: <4B9EDA8B.3070604@xxxxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
Bob,
I have been running both the Icom pre-amps with my 910 for some time now!
I do not need S/N ratio's or fancy tests to know that without them I
would have missed many a contact;
True, they are not brilliant (Icom does not even publish figures for
them) but they work and unless I feel like chucking the thick end of a
large amount of green at something else, they will continue to work.
And a large plus is that you can tx through them without fear of
goobering them up and they operate through the coax so no messy power
line runs with the coax!
Just my 2 cents worth of course!
David
KG4ZLB
On 3/15/2010 20:31, i8cvs wrote:
> ----- Original Message -----
> From: "Bob- W7LRD"<w7lrd@xxxxxxx.xxx>
> To:<amsat-bb@xxxxx.xxx>
> Sent: Tuesday, March 16, 2010 12:28 AM
> Subject: [amsat-bb] fun with preamps
>
>
>
> Smeter=0, preamp on Smeter=7. Signals "appear" better after backing down the
> volume with the preamp. I have 8-10 feet of LMR400uf from antenna to preamp,
> 50 feet of LMR400 to shack. I suppose I was expecting more "dramatic"
> results, I realize the AG-25 isn't the greatest and best, but it works well
> with the 910. Are these real world results for what I have. S7 noise level
> seems a bit high.
>
> Hi Bob, W7LRD
>
> No preamp noise Smeter=0, preamp on Smeter=7 means very small. Step 1
> without preamplifier tune your receiver in SSB or CW on a very weak carrier
> like a beacon and rotate your antenna into a null until you can barely hear
> a bit at about 1000 Hz over the noise. Step 2 now connect your preamplifier
> and see by hears if the Signal to Noise ratio S/N improves or not. If you
> can hear better the 1000 Hz bit your preamplier is useful othervise S meter
> = 7 means only or mostly the amplified preamplifier noise.
> Your test can be more accurate if instead to use your hears you connect an
> analog AC voltmeter at the audio output of your receiver.More is the swing
> of the AC voltmeter and better is the preamplifier i.e. lover is it's Noise
> Figure.
>
> Have fun.
>
> 73" de
>
> i8CVS Domenico
>
>
>
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. 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
>
>
------------------------------
Message: 9
Date: Tue, 16 Mar 2010 01:15:23 -0500
From: "Mike" <sar911@xxxxxxxxx.xxx>
Subject: [amsat-bb] K4T
To: <AMSAT-BB@xxxxx.xxx>
Message-ID: <008101cac4d0$10b68840$322398c0$@xxx>
Content-Type: text/plain; charset="us-ascii"
Well, the party is over and we had a great time and we hope you did too.
You can see a few of the pictures here: http://aroadventures.org/page26.html
We had a few glitches but it all worked out. We ran two 910H's. One with
yagis and one with egg beaters plus a portable station. It was pretty cool
to see CW and FM worked simultaneously. We hope this sets a new standard
for satellite operations on DXpeditions. Mark will give you an update
later.
By the way, we ran two satellite stations, two HF stations, inverter,
lighting and all acc. 24 hours a day all on green power for four days and
made over 8,000 contacts with only batteries and a wind turbine. The wind
turbine was making so much power that we never even took the 900 watts of
solar panels out of the case!
73's
Mike Forsythe, AC2V
------------------------------
Message: 10
Date: Tue, 16 Mar 2010 06:28:12 -0400
From: <n1jez@xxxxxxxxxxxxxxxxx.xxx>
Subject: [amsat-bb] Re: fun with preamps
To: "Bob- W7LRD" <w7lrd@xxxxxxx.xxx>, "AMSAT-BB" <amsat-bb@xxxxx.xxx>
Message-ID: <6224896D9BAC4D48BDC7D68B71A3C37D@xxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Hi Bob,
Here's a method I've used for setting preamp gain. Got it from GM3SEK.
=====
Here's a method that requires no test equipment at all. It comes from
G4DGU, who designed all the original muTek transverters and outboard
preamps to have adjustable gain. This method uses the sharp threshold
effect of FM detectors at low S/N ratios, and it allows you to optimize
the preamp/transverter gain for your local band noise conditions.
1. Turn the transverter/preamp gain well up.
2. Find a very weak but steady unmodulated carrier (off-air, not from a
signal generator or a local birdie). Rotate the antenna until you can
just detect the signal in FM mode.
3. Reduce the preamp/transverter gain until you hear the noise increase.
The FM threshold is sensitive to a small fraction of a dB in S/N.
4. Increase the gain just a little,to the point where you can't hear the
quieting improve much.
5. Switch back to a real DX mode.
Remember that every dB of unnecessary preamp/transverter gain will
probably subtract almost 1dB from your system intermod intercept!
The penalty of adjusting the gain correctly is that you're living just
above the "knee" where S/N will begin to deteriorate rapidly if
something changes. It's worthwhile to repeat this test every few months
- especially just before a contest.
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
====
73,
Mike, N1JEZ
AMSAT 29649
"A closed mouth gathers no feet"
>> Hello
>>
>> Just installed a AG-25 (Icom preamp) on my 2M cp yagi. No preamp noise
> Smeter=0, preamp on Smeter=7. Signals "appear" better after backing down
> the
> volume with the preamp. I have 8-10 feet of LMR400uf from antenna to
> preamp,
> 50 feet of LMR400 to shack. I suppose I was expecting more "dramatic"
> results, I realize the AG-25 isn't the greatest and best, but it works
> well
> with the 910. Are these real world results for what I have. S7 noise level
> seems a bit high.
>>
>> as always-thanks
>>
>> 73 Bob W7LRD
------------------------------
Message: 11
Date: Tue, 16 Mar 2010 10:58:30 +0000
From: "Mark Hammond N8MH" <marklhammond@xxxxx.xxx>
Subject: [amsat-bb] Re: K4T
To: "Mike" <sar911@xxxxxxxxx.xxx>, amsat-bb@xxxxx.xxx
Message-ID:
<1805660411-1268737162-cardhu_decombobulator_blackberry.rim.net-1841036818-@xx
xxxx.xxxx.xxxx.xx.xxxxxxxxxx>
Content-Type: text/plain
K4T was a super event, thanks to Mike and a great group of guys. Thanks to
all of you for your contacts!
On my early report I misread the log file, but our total contact number on
satellite and vhf/uhf was right at 300. Futher details about the trip, the
contacts, the station, and QSL info will be provided in the coming days.
Some of you had a clean sweep (worked us on all birds, and even more than
one mode (ssb/cw). I suspect K8YSE, N5UXT, and NZ5N are near the top :)
If you worked me as N8MH in Key West (EL94) before the trip just send me a
card directly. Tried SO-50 last night but couldn't get in...
73 for now.
Mark N8MH
------Original Message------
From: Mike
Sender: amsat-bb-bounces@xxxxx.xxx
To: AMSAT-BB@xxxxx.xxx
Subject: [amsat-bb] K4T
Sent: Mar 16, 2010 2:15 AM
Well, the party is over and we had a great time and we hope you did too.
You can see a few of the pictures here: http://aroadventures.org/page26.html
We had a few glitches but it all worked out. We ran two 910H's. One with
yagis and one with egg beaters plus a portable station. It was pretty cool
to see CW and FM worked simultaneously. We hope this sets a new standard
for satellite operations on DXpeditions. Mark will give you an update
later.
By the way, we ran two satellite stations, two HF stations, inverter,
lighting and all acc. 24 hours a day all on green power for four days and
made over 8,000 contacts with only batteries and a wind turbine. The wind
turbine was making so much power that we never even took the 900 watts of
solar panels out of the case!
73's
Mike Forsythe, AC2V
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------------------------------
Message: 12
Date: Tue, 16 Mar 2010 07:39:32 -0500
From: "Mike" <sar911@xxxxxxxxx.xxx>
Subject: [amsat-bb] K4T wind turbine
To: <AMSAT-BB@xxxxx.xxx>
Message-ID: <009501cac505$bafd47f0$30f7d7d0$@xxx>
Content-Type: text/plain; charset="us-ascii"
The wind turbine is a TLG500 http://www.tlgwindpower.com/default.htm . They
are bomb proof and worked flawlessly. The cost is $1,375.00 and if you
mention K4T as a promotion code they will give you $25.00 off of the
shipping. I built a special tripod for it to make it portable and we had it
up and making power in about ten minutes.
73's
Mike, AC2V
Hi Mike:
What kind of turbine were you running?
73, Jeff WB2SYK
------------------------------
_______________________________________________
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Not an AMSAT member? Join now to support the amateur satellite program!
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End of AMSAT-BB Digest, Vol 5, Issue 124
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