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CX2SA > SATDIG 22.04.08 15:05l 684 Lines 23231 Bytes #999 (0) @ WW
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To : SATDIG@WW
Today's Topics:
1. Ridge Test Results (Nathaniel S. Parsons)
2. Re: Ridge Test Results (Nathaniel S. Parsons)
3. Re: Kenwood TH-F6a (Greg D.)
4. Re: Delfi-C3 telemetry decoding software test (Alan)
5. Re: AMSAT Goes to the Races -- April 27 (Jeff Griffin)
6. CubeSats launch information (Mineo Wakita)
7. Fw: Re: Ridge Test Results (Roger Kolakowski)
8. Re: Ridge Test Results (Roger Kolakowski)
9. FINAL MONTHLY OSCAR-11 REPORT (Clive Wallis)
10. Re: FINAL MONTHLY OSCAR-11 REPORT (kb2m(AT)comcast.net)
11. Re: Ridge Test Results (Laurence 'Mike' Hammer)
----------------------------------------------------------------------
Message: 1
Date: Mon, 21 Apr 2008 23:06:42 -0400
From: "Nathaniel S. Parsons" <nsp25(AT)cornell.edu>
Subject: [amsat-bb] Ridge Test Results
To: "Amateur Radio Club" <hamradio-l(AT)list.cornell.edu>,
amsat-bb(AT)amsat.org, tcarc(AT)yahoogroups.com, "Dan Oltrogge"
<Oltrogge(AT)1earthresearch.com>, gs(AT)cusat.cornell.edu,
tc(AT)cusat.cornell.edu, "Patrick Raymond Conrad"
<prc23(AT)cornell.edu>
Message-ID:
<e9267a810804212006l7ee31f3fuf63e0c8e9dec4919(AT)mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Hi again, everyone.
It's a little overwhelming to get so much help at once, but thank you,
everyone, for all of it.
One clarification: I did indeed mean pF, not uF for the capacitors in the
matching circuit.
Also, we performed another ridge test this evening (another typo there: the
ridge is 3.18km from the roof where we have the ground station setup), using
the complete ground station (minus pre-amp), and TH-D7 with rubber duck.
We transmitted from the ground station, while varying the amount of
attenuators between the TS-2000 and coax to the antenna. The "PWR" column is
in the format (TH-D7)/(TS-2000). With each test, two 319-byte packets were
sent by the ground station in rapid succession. The results are below. If
any of this is not clear, I will do my best to clarify things.
Also, the entire test was performed at 437.405MHz, at 1200 baud, even though
we would like to operate at 9600. I have gotten 9600 baud to work when two
TH-D7's are across the room from each other, but since 9600 baud didn't work
during the initial configuration, we decided to just characterize the rubber
duck at 1200.
Ant. Pos. PWR Atten. Packets
Vertical .05W/5W 0dB 2/2
Vertical .5W/5W 50dB 0/2
Vertical .5W/5W 45dB 1/2
Vertical .5W/5W 45dB 2/2
Vertical .5W/5W 50dB 0/2
Horizontal .5/5 50dB 0/2
Horizontal .5/5 45dB 1/2
Horizontal .5/5 45dB 0/2
Horizontal .5/5 45dB 0/2
Horizontal .5/5 45dB 0/2
Horizontal .5/5 40dB 0/2
Horizontal .5/5 40dB 0/2
Horizontal .5/5 35dB 0/2
Horizontal .5/5 30dB 2/2
Horizontal .5/5 30dB 1/2
Horizontal .5/5 30dB 2/2
45 deg. .5/5 30dB 2/2
45 deg. .5/5 30dB 2/2
45 deg. .5/5 35dB 2/2
45 deg. .5/5 40dB 2/2
45 deg. .5/5 45dB 1/2
45 deg. .5/5 45dB 0/2
Comments? Concerns? Questions?
My initial interpretation of these data is that our square loop antenna has
a MUCH lower gain than is required, and something like a short length of
measuring tape would be a better substitute, as has been suggested by
numerous people.
-Nate
------------------------------
Message: 2
Date: Mon, 21 Apr 2008 23:43:12 -0400
From: "Nathaniel S. Parsons" <nsp25(AT)cornell.edu>
Subject: [amsat-bb] Re: Ridge Test Results
To: "Amateur Radio Club" <hamradio-l(AT)list.cornell.edu>,
amsat-bb(AT)amsat.org, gs(AT)cusat.cornell.edu,
tc(AT)cusat.cornell.edu, "Dan
Oltrogge" <Oltrogge(AT)1earthresearch.com>
Message-ID:
<e9267a810804212043k6fb9bd93xdf5a406f3bc6dd56(AT)mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
I'm sorry we didn't get in touch, but my cell phone died while we were out
there.
Were were listening on 146.610, but didn't hear anything except the time.
Maybe we weren't using it correctly?
If you could get all of that material tomorrow, that would be excellent. We
do have access to sanding paper, a file, and a grinding wheel, though.
On Mon, Apr 21, 2008 at 11:26 PM, F. Kevin Feeney <fkf1(AT)cornell.edu> wrote:
> Were you transmitting in just one direction or from TS to D7 and then from
> D7 to TS?
>
Via packet, only TS to D7 (some were sent the other way, but we were told
having attenuators on the RX side would give us unreliable data). By voice,
both directions, and while that signal was fuzzy at higher attenuation, it
never completely cut out. For the packets, we always received them on the
radio, but the number recorded was the amount passed on to the computer.
> Why list the power settings in each radio if you are only transmitting
> from the TS2000 to the D7? That confused me.
Just for completeness.
>
> How successful have you been at running the radios in 9600 baud mode in
> previous testing? If you don't have many weeks of positive results in that
> mode at this point with whatever antennas, I'd be very wary of committing to
> a launch.
Not very. We could complete the mission at 1200 baud, though, it would just
take longer to move data back and forth.
> so what are the power listings for each radio telling us? To me I think
> I'm seeing that your circularly polarized antenna isn't quite as good in
> horizontal mode as in vertical? You have to have less attenuation in place
> to get two good packets per two tries for the same power settings in
> horizontal as for vertical. looks like about a 15 db difference? (30 vs 45?)
> That says your circular antenna "circularity" is suspect. Is it a helix?
> Crossed yagis with phasing harness? Is it up in the air off the support
> structure? Are the feedlines trailed out the back of the antenna, or do they
> come down through the elements to the mast?
I'm sorry that I wasn't clear, but all our rotations were in the direction
of the other station. So, if an observer were looking at us from the side,
Vertical:
"satellite" |
XXXXX- Ground
Horizontal:
"satellite" --
XXXXX-Ground
45 deg:
"satellite" /
XXXXX-Ground
So we didn't really test the circularity of the ground antenna, but the gain
pattern of the rubber duck.
> Wait - were you testing the loop during any of this? I thought all of the
> measurements were made with the rubber duck only in three orientations,
> vertical, horizonatal and 45 degree. Where is the loop data shown?
The loop data is the 10 dB figure mentioned in my first email. Under these
same conditions on Friday, the loop only worked up to 10dB.
Also, I can use a network analyzer tomorrow at 2PM. Is it worth analyzing
the square loop antenna at this point?
-Nate
------------------------------
Message: 3
Date: Mon, 21 Apr 2008 22:04:40 -0700
From: "Greg D." <ko6th_greg(AT)hotmail.com>
Subject: [amsat-bb] Re: Kenwood TH-F6a
To: <amsat-bb(AT)amsat.org>
Message-ID: <BLU133-W446311B3E042C16E53984BA9E00(AT)phx.gbl>
Content-Type: text/plain; charset="iso-8859-1"
Also consider that the performance on non-ham frequencies is limited,
especially shortwave. I can't even pick up WWV from northern California
without an external antenna, and the AM/FM receiver is mediocre. Selectivity
and image rejection is also not that great, but it hasn't been a big problem
in practice.
But, I'm glad I have the F6. Besides the all-mode, all band reception, it is
very compact and has good battery life. The receive coverage is very broad,
including some parts of the vhf band that none of the other HTs seem to have.
It came in very handy a few years ago when my daughter was staring in the high
school play, and the wireless mikes (180 mhz band) kept going out. I was able
to listen in and alert the audio crew if there was a problem, before each cast
member went live.
Definitely get a better antenna (there are several taller tri-band ones on the
market), and enjoy.
My only other wish (besides the Rx sensitivity) is that they could figure out
how to transmit in SSB/CW. That would make it complete.
Greg KO6TH
----------------------------------------
> From: clintbrad4d(AT)earthlink.net
> Date: Mon, 21 Apr 2008 11:23:21 -0700
> To: amsat-bb(AT)amsat.org
> Subject: [amsat-bb] Re: Kenwood TH-F6a
>
>> .. is the TH-F6A my best choce for HT? for sats, ... or at least in
>> the top two?? Before I go down thr street to HRO and plunk down the
>> money...
>
> The TH-F6a is an excellent performer. It is NOT, however, a true full-
> duplex unit. It is a tri-band, dual receive unit. Full power output
> on all three bands (2M, 220, and 440).
>
> If you want/need dual-receive, it's a great unit. Minor drawback:
> Using its optional AA Alkaline pack, you're only operating at 1/2 W.
>
> Clint Bradford,K6LCS
> 909-241-7666
> _______________________________________________
> Sent via AMSAT-BB(AT)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
_________________________________________________________________
Use video conversation to talk face-to-face with Windows Live Messenger.
http://www.windowslive.com/messenger/connect_your_way.html?ocid=TXT_TAGLM_WL_R
efresh_messenger_video_042008
------------------------------
Message: 4
Date: Tue, 22 Apr 2008 00:32:26 -0500
From: "Alan" <ve4yz(AT)mts.net>
Subject: [amsat-bb] Re: Delfi-C3 telemetry decoding software test
To: "'Wattage Perera'" <ve4wkp(AT)mts.net>, <amsat-bb(AT)amsat.org>
Message-ID: <000601c8a43a$3fcc9650$0602a8c0(AT)athlon>
Content-Type: text/plain; charset="us-ascii"
Thanks Kumara... It works and in the lower right "Status Message" window I
can confirm that the file was uploaded to the Delfi server.
In my XP Pro there is only Stereo Mix but Rascal captures and decoded while
running the WAV file in Windows Media Player.
-----Original Message-----
From: amsat-bb-bounces(AT)amsat.org [mailto:amsat-bb-bounces(AT)amsat.org] On
Behalf Of Wattage Perera
Sent: April 21, 2008 7:26 PM
To: amsat-bb(AT)amsat.org
Subject: [amsat-bb] Delfi-C3 telemetry decoding software test
Hi to the BB,
I was able to locally test the Delfi-C3 RASCAL software using the 5MB
telemetry sound file from the Delfi-C3 website using my computer with the
following method.
Set your computer Sound Recording Device Properties using the following
path. I am using Windows XP Home Edition.
Control Panel ---- Sounds and Audio Devices ---- Sounds and Audio Devices
Properties ---- Click on Audio tab ---- Click on Sound Recording Volume tab
---- Select Mono Mix on Sound Recorder Properties ---- Set the recording
volume level to half way on the scale. Now make sure you have a check mark
in the Sound Recorder select box.
Download the 5MB WAV file onto your desktop from the following link in the
Delfi-C3 website:
http://www.delfic3.nl/index.php?option=com_content&task=view&id=23&Itemid=11
5
Open the computer Sound Recorder program ( All Programs ---- Accessories
---- Entertainment ---- Sound Recorder ) or use the Windows Media Player.
Play back the telemetry sound file you downloaded.
Open the Delfi-C3 RASCAL software. Now you should see the software screen
decoding the playback telemetry sound file. You can set the audio level by
adjusting the computer Sound Recorder Volume level setting.
73,
Kumara Perera VE4WKP
_______________________________________________
Sent via AMSAT-BB(AT)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
------------------------------
Message: 5
Date: Tue, 22 Apr 2008 06:53:01 -0400
From: "Jeff Griffin" <kb2m(AT)comcast.net>
Subject: [amsat-bb] Re: AMSAT Goes to the Races -- April 27
To: "AMSAT BB" <amsat-bb(AT)amsat.org>
Message-ID: <004401c8a467$0a9cbcd0$6801a8c0(AT)server>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Now that is cool. I'm an AMSAT and a Ford guy. I have three Ford's,
including 2 Mustangs, one of which is my pride and joy, a 2007 Roush 427R.
73 Jeff kb2m
----- Original Message -----
From: "Tom Clark, K3IO" <k3io(AT)verizon.net>
To: "AMSAT BB" <amsat-bb(AT)amsat.org>
Sent: Tuesday, April 22, 2008 12:03 AM
Subject: [amsat-bb] AMSAT Goes to the Races -- April 27
> This coming Sunday, April 27th, AMSAT will have its premiere at a major
> sports car race -- The Bosch Engineering 250 at the Virginia
> International Raceway (VIR) Grand-Am Rolex Sports Car Series; VIR is
> located near Danville, VA on the VA/NC border.
>
>
> Brad Jaeger (see http://www.bradjaeger.com) is the son of AMSAT member
> Jim Jaeger (K8RQ) and is piloting the bright yellow #77 Doran Racing
> Kodak Ford machine (which you can see at
> http://www.bradjaeger.com/?q=node/110 and at
> http://www.grand-am.com/rolex/drivers/driver.cfm?did=1110).
>
>
> K8RQ has arranged for AMSAT to display its colors on Brad's car on a
> "space available" basis. If you can make it to Danville for the weekend,
> the detailed schedule of events can be found at
> http://www.grand-am.com/assets/08VIROfficialSched2.pdf. But if you can't
> make it, the race will be carried on the cable SPEED channel from 12:00
> to 15:00 EDT on Saturday, May 3rd.
------------------------------
Message: 6
Date: Tue, 22 Apr 2008 20:12:10 +0900
From: Mineo Wakita <ei7m-wkt(AT)asahi-net.or.jp>
Subject: [amsat-bb] CubeSats launch information
To: amsat-bb(AT)amsat.org
Message-ID: <1BC8A469B58639ei7m-wkt(AT)asahi-net.or.jp>
Content-Type: text/plain; charset=us-ascii
Launch 28Apr08 03:53UTC
Launch Vehicle: PSLV-C9
Preliminary TLE
1 00000U 00000C 08119.17443982 .00000000 00000-0 00000-0 0 0013
2 00012 97.9497 178.9014 0004270 015.5590 198.2466 14.79780033 00004
---------------------------------------------------------------------
Satellite Uplink Downlink Beacon Mode Callsign
CUTE1.7 1267.600 . . 9600bd GMSK JQ1YTC
CUTE1.7 . 437.475 . 9600bd GMSK JQ1YTC
CUTE1.7 . 437.475 . 1200bd AFSK JQ1YTC
CUTE1.7 . . 437.275 CW
SEEDS . 437.485 . FM,CW,Talk JQ1YGU
DELFI-C3 . 145.870 . 1200bd BPSK DLFIC3
DELFI-C3 435.570-530 145.880-920 145.930 FM,CW
COMPASS-1 . 437.405 . 1200bd AFSK
COMPASS-1 . . 437.275 CW
AAUSAT-II . 437.425 437.425 1200bd AFSK OZ2CUB
AAUSAT-II . 437.425 437.425 9600bd FSK OZ2CUB
CANX-2 . 437.478 . 32Kbd- VA3SFL
CANX-2 . 2407.650 . 256Kbd GMSK VA3SFL
---------------------------------------------------------------------
http://showcase.netins.net/web/wallio/CubeSat.htm
http://www.dk3wn.info/calendar/satellit.php?language=german
------------------------------
Message: 7
Date: Tue, 22 Apr 2008 08:01:03 -0400
From: "Roger Kolakowski" <rogerkola(AT)aol.com>
Subject: [amsat-bb] Fw: Re: Ridge Test Results
To: <amsat-bb(AT)amsat.org>
Message-ID: <004601c8a470$8b21ce00$0200a8c0(AT)Tanguray>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: DBowman
To: G0MRF(AT)aol.com
Cc: rogerKola(AT)aol.com
Sent: Tuesday, April 22, 2008 7:22 AM
Subject: RE: [amsat-bb] Re: Ridge Test Results
Thanks for the copy Nate.
No need to reply to what follows, but it may be useful. I'll look out for the
next update.
Congratulations, That's really good progress for just a couple of days.
I think 45dB will take you just to about 600km, but really there's room for
improvement yet.
The photo's show the antenna very well. A couple of thoughts.
It looks like it is mounted on FR4 PCB and this is an inch or so from the main
structure. Is there another antenna on the other side? - The RF will not pass
through the satellite.
The FR4 will affect the properties especially if you have applied glue at a
voltage node on the antenna.
Also, I see one side is very closely coupled into a track running from the
solar cells. That will not help.
My guess is that the antenna will be really bad on the VNA. - Remember when
testing that the VNA will show you return loss. You will know if the return
loss is between 0dB and 6dB that the antenna does not work. But please be
aware that even if you see a 'good' return loss e.g. 15 to 30dB, Then that
may not indicate that the energy from your transmitter is being radiated. -
After all, a 50 Ohm resistor has a wonderful return loss, but does not
radiate. Look for a nice dip at your design frequency.
If you have to replace the antenna then a whip / steel tape would be OK but
needs to work against part of the structure. - Which looking at your satellite
will be difficult to do.
A good solution may be to make a dipole from two solid metal rods and fit them
to the same spot where your antenna is at present. - But clear of other
objects. Say 1 inch above the surface. Another choice would be a folded
dipole, but you will need to match that from apx 200 to 300 ohms, back down to
50 ohms.
If you decide on the simple (but reliable) dipole, mount the elements off the
PCB material and only support them at the center not at the ends. The ends are
a high voltage point and anything near them or touching will affect the
performance.
I think your original estimate of 57dB is spot on. Well done.
Path loss for 3.18km = -95.26dB
Path loss for 2000km = -151.23
Difference from ridge to space = 56dB
So you have to find another 12dB + some margin for loss due to spin or
pointing angle.
1) It could be that the rubber duck is only 50% efficient. - So that
could be 3dB off the total. But your new antenna may no be much better.
2) You have not mentioned ground station feeder loss. Without the preamp
that will be added to the total. On 70cms you could be looking at 4 - 6dB.
So, possibly only 6 or 7dB to find !!!
Your TS2000 has an S meter. On SSB or CW the sensitivity is as follows. This
is very approximate, but it may help. This is with RF gain at max and no pre-
amp.
S1 = - 113dBm at antenna.
S3 - 110dBm
S5 - 107
S7 - 102
S9 - 93dBm
>From what you have said so far 0.5W of carrier from the ridge should give a
little over S9 when in SSB or CW. If you can check this with a lab sig
generator and your TS2000 you will be able to do some really good measurements
on your system.
I have one final thought on the missing dBs. Or the lack of 9600.
You mention that you have not been able to use 9600 and you are still not 100%
reliable on 1200.
It could be that you need to optimize the modulation level on the transmitter.
That is very important because if the modulation is too high. - i.e. if the
volume going into the radio is too high, then the bandwidth on FM will be much
greater then necessary. The reason this is important, is that if the
transmitted bandwidth of the signal exceeds the width of the filters in the
receiver, then the demodulated audio will be distorted and you will never
recover the data. (I think something like this happened to CAPE 1)
So, spend a little time optimizing the transmitter either by experimentation,
or by calculating the bandwidth and then attaching the transmitter to a
spectrum analyzer to make the adjustment. - There probably isn't time, but the
proper way would be to generate a test signal at 9600 and then examine the
recovered audio for distortion / linearity.
Give the TS2000 a try with OSCAR 51 on 435.300 (starting 10kHz high for
Doppler and finishing 10k low)
April 1 - April 30
FM Repeater, V/U
Uplink: 145.920 MHz FM, NO PL Tone
Downlink: 435.300 MHz FM
9k6 Digital L/U BBS and Telemetry
Uplink: 1268.700 MHz FM
Downlink: 435.150 MHz FM
Good Luck
David
------------------------------------------------------------------------------
--
From: G0MRF(AT)aol.com [mailto:G0MRF(AT)aol.com]
Sent: 22 April 2008 08:44
To: DBowman
Subject: Fwd: [amsat-bb] Re: Ridge Test Results
In a message dated 22/04/2008 05:39:41 GMT Standard Time, nsp25(AT)cornell.edu
writes:
I'm sorry we didn't get in touch, but my cell phone died while we were out
there.
Were were listening on 146.610, but didn't hear anything except the time.
Maybe we weren't using it correctly?
If you could get all of that material tomorrow, that would be excellent. We
do have access to sanding paper, a file, and a grinding wheel, though.
On Mon, Apr 21, 2008 at 11:26 PM, F. Kevin Feeney <fkf1(AT)cornell.edu>
wrote:
> Were you transmitting in just one direction or from TS to D7 and then from
> D7 to TS?
>
Via packet, only TS to D7 (some were sent the other way, but we were told
having attenuators on the RX side would give us unreliable data). By voice,
both directions, and while that signal was fuzzy at higher attenuation, it
never completely cut out. For the packets, we always received them on the
radio, but the number recorded was the amount passed on to the computer.
> Why list the power settings in each radio if you are only transmitting
> from the TS2000 to the D7? That confused me.
Just for completeness.
>
> How successful have you been at running the radios in 9600 baud mode in
> previous testing? If you don't have many weeks of positive results in that
> mode at this point with whatever antennas, I'd be very wary of committing
to
> a launch.
Not very. We could complete the mission at 1200 baud, though, it would just
take longer to move data back and forth.
> so what are the power listings for each radio telling us? To me I think
> I'm seeing that your circularly polarized antenna isn't quite as good in
> horizontal mode as in vertical? You have to have less attenuation in place
> to get two good packets per two tries for the same power settings in
> horizontal as for vertical. looks like about a 15 db difference? (30 vs
45?)
> That says your circular antenna "circularity" is suspect. Is it a helix?
> Crossed yagis with phasing harness? Is it up in the air off the support
> structure? Are the feedlines trailed out the back of the antenna, or do
they
> come down through the elements to the mast?
I'm sorry that I wasn't clear, but all our rotations were in the direction
of the other station. So, if an observer were looking at us from the side,
Vertical:
"satellite" |
XXXXX- Ground
Horizontal:
"satellite" --
XXXXX-Ground
45 deg:
"satellite" /
XXXXX-Ground
So we didn't really test the circularity of the ground antenna, but the gain
pattern of the rubber duck.
> Wait - were you testing the loop during any of this? I thought all of the
> measurements were made with the rubber duck only in three orientations,
> vertical, horizonatal and 45 degree. Where is the loop data shown?
The loop data is the 10 dB figure mentioned in my first email. Under these
same conditions on Friday, the loop only worked up to 10dB.
Also, I can use a network analyzer tomorrow at 2PM. Is it worth analyzing
the square loop antenna at this point?
-Nate
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