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CX2SA > SATDIG 18.02.13 21:03l 371 Lines 12162 Bytes #999 (0) @ WW
BID : AMSATBB852
Read: GUEST
Subj: AMSAT-BB-digest V8 52
Path: IZ3LSV<IW0QNL<JH4XSY<JE7YGF<7M3TJZ<CX2SA
Sent: 130218/2001Z @:CX2SA.SAL.URY.SA #:3555 [Salto] FBB7.00e $:AMSATBB852
From: CX2SA@CX2SA.SAL.URY.SA
To : SATDIG@WW
Today's Topics:
1. Where to find MGF-1302 ? (Gregory Beat)
2. OSCAR 7 close call (Mike Farkas)
3. ShindaiSat to have Optical Morse Code Beacon (Trevor .)
4. Fwd: UPDATE: OSCAR 7 Close Approach Notification
(Andrew Glasbrenner)
5. iss and me (Daniel)
6. Re John Heath G7HIA, SK (Clive Wallis)
7. QFHA for SO-50... polarization issue ???
(Ing. Pavel Milanes Costa)
8. Re: QFHA for SO-50... polarization issue ??? (Art McBride)
----------------------------------------------------------------------
Message: 1
Date: Sun, 17 Feb 2013 15:10:14 -0600
From: Gregory Beat <gregory.beat@xxxxxxx.xxx>
To: "Amsat-bb@xxxxx.xxxx <Amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Where to find MGF-1302 ?
Message-ID: <5C73E2B4-EA44-4AF2-9D61-BB21080BD365@xxxxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
Compilation of the replies for requests where to find MGF-1302's, in past 14
years.
Thanks to contributions by: CT1DMK, CT1FAK, W6OAL, WA7TDU, EA1YO, EA4BAS,
VE4MA, NP4C, AL7OB, N7LQ & VE7BQH for their help.
MGF-1302's can be found at:
SPAIN
EA3GCY (http://iws.es/ea3gcy/)
SSB electronics (Barcelona)
USA
RF-Parts
WA5VJB (E-Mail: RDILABS@xx.xxxx
Down East Microwave (www.downeastmicrowave.com) 5 units = US $25
Advanced Receiver Research (http://www.advancedreceiver.com/) Price: $11.50
plus mailing (Last updated on 1-Dec-2000)
Other places
R.F. Elettronica (I2FHW)
Lins Berben PA3CMC had a lot for sale. He asks 2.5 Euros/each plus shipping
(Last updated on 17-May-2003)
Rainer Jager DC7XY
DB6NT (Kuhne electronic)
CT1DMK (E-Mail: cupido@xxxx.xx.xxx
Barend Hendriksen Electronics in the Netherlands
(http://www.xs4all.nl/~barendh/Indexeng.htm)
===
w9gb
------------------------------
Message: 2
Date: Sun, 17 Feb 2013 17:34:34 -0500
From: Mike Farkas <mikef1234@xxxxx.xxx>
To: AMSAT-BB <AMSAT-BB@xxxxx.xxx>
Subject: [amsat-bb] OSCAR 7 close call
Message-ID:
<CAN8j7+ckVg3k_PVQEEu4jrs7Ltc1A6UyenxYzTMCit_qsNohXg@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Thanks for the post about what it was. I was wondering what it could have
been with so much activity going on!
73's
Mike/N8GBU
------------------------------
Message: 3
Date: Sun, 17 Feb 2013 23:06:37 +0000 (GMT)
From: "Trevor ." <m5aka@xxxxx.xx.xx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] ShindaiSat to have Optical Morse Code Beacon
Message-ID:
<1361142397.79712.YahooMailClassic@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=utf-8
A 20 kg spacecraft, I don't know what power the LED's will be running but
they may be a lot brighter than the 1 kg FITSAT-1. Their website indicates a
2013 launch.
See http://www.amsat-uk.org/
----
73 Trevor M5AKA
AMSAT-UK http://www.amsat-uk.org/
Join or Renew your AMSAT-UK membership at
http://shop.amsat.org.uk/shop/category_7/Membership-of-AMSAT-UK.html
----
------------------------------
Message: 4
Date: Sun, 17 Feb 2013 18:19:22 -0500
From: Andrew Glasbrenner <glasbrenner@xxxxxxxxxx.xxx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Fwd: UPDATE: OSCAR 7 Close Approach Notification
Message-ID: <9B27E28C-2099-4978-B19B-C3E9AA6E94D5@xxxxxxxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
Updated, and a little bigger miss.
Sent from my iPhone
> Subject: UPDATE: OSCAR 7 Close Approach Notification
>
> Sir/Ma'am,
>
> The United States Joint Space Operations Center (JSpOC) has updated a
> predicted conjunction between OSCAR 7 (SCC# 7530) and SCC# 18116.
>
> Primary Object: OSCAR 7 (SCC# 7530)
> Secondary Object: SCC# 18116
> Time of Closest Approach: 18 FEB 2013 22:06 UTC
>
> Overall miss distance: 81 meters
> Radial (dU) miss distance: 32 meters
> In-Track (dV) miss distance: -36 meters
> Cross-track (dW) miss distance: 66 meters
>
> Primary Radial Error (U): 10 meters
> Primary In-Track Error (U): 39 meters
> Primary Cross-track Error (U): 8 meters
>
> Secondary Radial Error (U): 10 meters
> Secondary In-Track Error (U): 43 meters
> Secondary Cross-Track Error (U): 10 meters
>
>
------------------------------
Message: 5
Date: Sun, 17 Feb 2013 17:13:15 -0800
From: "Daniel" <kf1buz@xxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] iss and me
Message-ID: <011c01ce0d75$21f174d0$65d45e70$@xxx>
Content-Type: text/plain; charset="us-ascii"
Hey every one,
I have been having issues with the iss I can hear its packet bursts but
have now been able to connect with my loc or talk to others
I a using mix w and have not had any issues till now.
Anyone with mix w exp or settings please e- mail me off line
Thank you
Dan in DM09
------------------------------
Message: 6
Date: Mon, 18 Feb 2013 09:30:19 +0000
From: Clive Wallis <clive@xxxxx.xx.xx>
To: amsat <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re John Heath G7HIA, SK
Message-ID: <5121F4AB.9060106@xxxxx.xx.xx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I was very saddened to learn of John's passing. We had exchanged many
e-mails during the last few years. I didn't know John very well,
although we had met at the ASAT-UK Colloquium on several occasions.
Topics we discussed by e-mail included processing Delphi 3C telemetry,
OSCAR-11 spin rate, automatic Doppler tracking and ARISSat-1 decay.
John was very active in using our satellites and promoting their use to
others. For several years he was net controller of the Midlands two
metre AMSAT net. He also wrote the Space column for RSGB's RadCom
magazine for a number of years. He contributed many articles to OSCAR
News, recently in the September 2012 issue about ARISSat-1 orbital
decay. His last contribution to OSCAR News was a short item in the
December issue, congratulating AMSAT-UK on their 200th issue of the
magazine. He included a photograph of himself, Astronaut Ron Parise
WA4SIR and Geoff Perry, founder of the Kettering Group of satellite
observers. It was taken at the 1998 Colloquium.
During the course of our discussions John mentioned that he was having
some unpleasant hospital treatment. He also told me about his working
career, which I thought may be of interest.
As a teenager he was interested in organic chemistry and went to work in
industry, eventually in the R&D department at Bakelite in Tyseley,
Birmingham. In the 1960's/70's he worked on the phenolic resins used to
make copper clad PCB material, and did the first industrial synthesis on
nonyl phenol by ion exchange. There were massive world stocks of Nonene
at knock down prices so they were looking for a way to use it to make
phenol/formaldehyde resins used in PCB manufacture.
His YL Pam at that time worked in a small hairdressing supplies
business and he sometimes worked with her when they needed extra staff
to cover late night opening. After his marriage to Pam, her firm decided
to open a branch in Leicester and they were offered the opportunity to
re-locate and run the new operation. Together they built up the
business, diversifying into related activities with a skin care
manufacturing company (where his science background was invaluable), a
beauty products wholesale business and a mail order operation. The
business expanded from 6 people to a staff of nearly 200 on four sites.
John said that Amateur radio helped to keep him sane by giving him a
totally different set of things to think about and emptied his head of
business concerns for a few hours each week!
A few years ago Pam was diagnosed with a serious illness and confined to
a wheel chair. This caused them to bring forward their retirement
plans and they moved to Devon.
My condolences to Pam, family & friends.
RIP John, we will miss you.
Clive Wallis G3CWV
------------------------------
Message: 7
Date: Sat, 16 Feb 2013 23:21:30 -0500
From: "Ing. Pavel Milanes Costa" <pavel@xxxxx.xx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] QFHA for SO-50... polarization issue ???
Message-ID: <51205ACA.3010004@xxxxx.xx>
Content-Type: text/plain; charset="iso-8859-1"; Format="flowed"
This weekend I tested a Quadrifiliar Helicoidal Antenna for 70cm (LHCP)
I designed it by the online calculations of jcoppens on the internet...
It is a 1/2 turn and 1 lambda, about 5 meters of elevation with ~25 cm
of RG-58U (a section of it is coiled to form a balum) and then ~15
meters of A.H. LDF4-50A down to the shack directly to the radio, of
course BNC to N adapter on the antenna and N to PL259 on the radio
side... It's at mast top.
Results are good... In passes of over 20 degrees (almost the real
horizon here) I have a good copy, until... TCA, in which I lost the
signal completely...
TCA = Time of Closest Approach.
In northbound passes (I've not tested it in southbound) it work as I
just said...
I have been reading and investigating this strange issue and I think it
is due to polarization...
I had read that SO-50 is linear polarized on 2m AND 70cm with aprox 45
degrees each other...
Then Linear to LHCP in the worst case is 3dB loss (half power) but
consistent over the entire pass... or have SO-50 some
circular/elliptical component in it's signals that renders useless the
antenna after TCA? spin maybe?
There is any chapter of the book I missed or other variable(s) that I
have not taking into account here?
Any comment, link or other kinds of help are welcomed..
73 de CO7WT.
------------------------------
Message: 8
Date: Mon, 18 Feb 2013 10:32:02 -0800
From: "Art McBride" <kc6uqh@xxx.xxx>
To: "'Ing. Pavel Milanes Costa'" <pavel@xxxxx.xx>,
<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: QFHA for SO-50... polarization issue ???
Message-ID: <729F120613BA471ABF380AF3BAC946B3@xxxxxx>
Content-Type: text/plain; charset="us-ascii"
Ing. Pavel,
There are a whole series of QFH antennas. 1/4,turn, 1/4 wavelength through 1
turn 1 Wavelength.
Gain at the horizon is determined by the ratio of the axial length in
fractions of a wave length. The best performance I have obtained is a 1
wavelength per side, 1 turn, for good gain at the horizon with an axial
length of .65 wavelengths. You need the least gain at the Zenith as the
satellite is closest in range at that point.
The best reference I found is "Resonant Quadrifilar Helix Design" by C.C.
Kilgus, December 1970 Issue, of the Microwave Journal, Pgs 49-54.
73,
Art KC6UQH
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of Ing. Pavel Milanes Costa
Sent: Saturday, February 16, 2013 8:22 PM
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] QFHA for SO-50... polarization issue ???
This weekend I tested a Quadrifiliar Helicoidal Antenna for 70cm (LHCP)
I designed it by the online calculations of jcoppens on the internet...
It is a 1/2 turn and 1 lambda, about 5 meters of elevation with ~25 cm
of RG-58U (a section of it is coiled to form a balum) and then ~15
meters of A.H. LDF4-50A down to the shack directly to the radio, of
course BNC to N adapter on the antenna and N to PL259 on the radio
side... It's at mast top.
Results are good... In passes of over 20 degrees (almost the real
horizon here) I have a good copy, until... TCA, in which I lost the
signal completely...
TCA = Time of Closest Approach.
In northbound passes (I've not tested it in southbound) it work as I
just said...
I have been reading and investigating this strange issue and I think it
is due to polarization...
I had read that SO-50 is linear polarized on 2m AND 70cm with aprox 45
degrees each other...
Then Linear to LHCP in the worst case is 3dB loss (half power) but
consistent over the entire pass... or have SO-50 some
circular/elliptical component in it's signals that renders useless the
antenna after TCA? spin maybe?
There is any chapter of the book I missed or other variable(s) that I
have not taking into account here?
Any comment, link or other kinds of help are welcomed..
73 de CO7WT.
------------------------------
_______________________________________________
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End of AMSAT-BB Digest, Vol 8, Issue 52
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