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CX2SA > SATDIG 23.04.10 06:27l 884 Lines 27629 Bytes #999 (0) @ WW
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From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. Re: Arecibo on 432 MHz Moon Bounce (some calculations) (Idle-Tyme)
2. Re: Arecibo on 432 MHz Moon Bounce (some calculations) (Idle-Tyme)
3. Congrats to K7CWQ (Clint Bradford)
4. Re: Arecibo on 432 MHz Moon Bounce (some calculations) (i8cvs)
5. Re: Congrats to K7CWQ (davekn4ok@xxx.xxxx
6. Re: Arecibo on 432 MHz Moon Bounce (some calculations)
(Mark Hammond N8MH)
7. Re: Arecibo on 432 MHz Moon Bounce (some calculations) (Sebastian)
8. : For sale, Yaesu VX-3R HT, ARR RF switched pre amp (
pre-amp sold) (Michael Tondee)
9. Tickets from Space (Clint Bradford)
10. Re: Arecibo on 432 MHz Moon Bounce (some calculations)
(John Magliacane)
11. Re: UHF/VHF Polarization Switch (Bruce Semple)
12. Re: Tickets from Space (D. Craig Fox)
13. Re: Arecibo on 432 MHz Moon Bounce (some calculations)
(Stephen Melachrinos)
14. Satellite VUCC # 194 (LOREN RASMUSSEN)
15. Deployable Solar Panels on a 1U CubeSat (Trevor .)
16. Re: Satellite VUCC # 194 (John Neeley)
17. Re: Arecibo on 432 MHz Moon Bounce (some calculations)
(Art McBride)
----------------------------------------------------------------------
Message: 1
Date: Thu, 22 Apr 2010 14:58:29 -0500
From: Idle-Tyme <nss@xxx.xxx>
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
To: Sil - ZL2CIA <zl2cia@xxxxx.xxx>
Cc: AMSAT-BB <amsat-bb@xxxxx.xxx>
Message-ID: <4BD0AA65.80306@xxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Wow that's all messed up?
I'm 52 and this is the very first time i have ever seen anything like
this and i have been dealing with science worldwide all my life. wow.
Joe
The Original Rolling Ball Clock
Idle Tyme
Idle-Tyme.com
http://www.idle-tyme.com
On 4/22/2010 1:14 PM, Sil - ZL2CIA wrote:
> Idle-Tyme wrote:
>> On 4/21/2010 8:25 PM, i8cvs wrote:
>>>> Comma or no comma, shouldn't matter
>>>> 1000 mega watts or 1,000 Mega watts is still one thousand million
>>>> watts! NOT one thousands watts. true?
>>>>
>>>> The Original Rolling Ball Clock
>>>> Idle Tyme
>>>> Idle-Tyme.com
>>>> http://www.idle-tyme.com
>>>>
>>> Hi Idle-Tyme
>>>
>>> I don't agree with your statement:
>>>
>>> 1000 mega watt are one thousand million watt
>>> 1,000 mega watt or 1.000 mega watt is only one million watt because
>>> zero after the comma means nothing like 1,0000000000000 is still
>>> one million watt or 1 MW
>> NO! it's a comma, not a decimal point! it's one thousand, one
>> thousand written 1000 or 1,000 is still one thousand they are exactly
>> the same.
> That's only true in the English speaking world, and this is the cause
> of the confusion in this debate.
>
> In the Netherlands (and most of Europe), you would write one thousand
> million watts as 1.000 megawatts.
>
> The decimal indicator in Europe is a comma.
> For example,
> 1,5 means one and a half
> 1.000.000 means one million.
>
> Sil
> (ex PA3HIL)
>
>
------------------------------
Message: 2
Date: Thu, 22 Apr 2010 14:59:07 -0500
From: Idle-Tyme <nss@xxx.xxx>
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
To: Sil - ZL2CIA <zl2cia@xxxxx.xxx>
Cc: AMSAT-BB <amsat-bb@xxxxx.xxx>
Message-ID: <4BD0AA8B.1010400@xxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
do you calculators have commas?
The Original Rolling Ball Clock
Idle Tyme
Idle-Tyme.com
http://www.idle-tyme.com
On 4/22/2010 1:14 PM, Sil - ZL2CIA wrote:
> Idle-Tyme wrote:
>> On 4/21/2010 8:25 PM, i8cvs wrote:
>>>> Comma or no comma, shouldn't matter
>>>> 1000 mega watts or 1,000 Mega watts is still one thousand million
>>>> watts! NOT one thousands watts. true?
>>>>
>>>> The Original Rolling Ball Clock
>>>> Idle Tyme
>>>> Idle-Tyme.com
>>>> http://www.idle-tyme.com
>>>>
>>> Hi Idle-Tyme
>>>
>>> I don't agree with your statement:
>>>
>>> 1000 mega watt are one thousand million watt
>>> 1,000 mega watt or 1.000 mega watt is only one million watt because
>>> zero after the comma means nothing like 1,0000000000000 is still
>>> one million watt or 1 MW
>> NO! it's a comma, not a decimal point! it's one thousand, one
>> thousand written 1000 or 1,000 is still one thousand they are exactly
>> the same.
> That's only true in the English speaking world, and this is the cause
> of the confusion in this debate.
>
> In the Netherlands (and most of Europe), you would write one thousand
> million watts as 1.000 megawatts.
>
> The decimal indicator in Europe is a comma.
> For example,
> 1,5 means one and a half
> 1.000.000 means one million.
>
> Sil
> (ex PA3HIL)
>
>
------------------------------
Message: 3
Date: Thu, 22 Apr 2010 13:36:48 -0700
From: Clint Bradford <clintbradford@xxx.xxx>
Subject: [amsat-bb] Congrats to K7CWQ
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Message-ID: <DAB2BF0F-2B52-4EAA-A568-283BAD1025C0@xxx.xxx>
Content-Type: text/plain; charset=us-ascii
Loren, K7CWQ, just received his VUCC award - using a FT-60R and Arrow Sat
Antenna as his station.
CONGRATULATIONS, Loren!
Clint, K6LCS
http://www.work-sat.com
------------------------------
Message: 4
Date: Thu, 22 Apr 2010 23:12:16 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
To: "Sil - ZL2CIA" <zl2cia@xxxxx.xxx>, "Idle-Tyme" <nss@xxx.xxx>
Cc: AMSAT-BB <amsat-bb@xxxxx.xxx>
Message-ID: <000801cae260$7cc7ff20$0201a8c0@xxx.xx>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "Sil - ZL2CIA" <zl2cia@xxxxx.xxx>
To: "Idle-Tyme" <nss@xxx.xxx>
Cc: "i8cvs" <domenico.i8cvs@xxx.xx>; "AMSAT-BB" <amsat-bb@xxxxx.xxx>
Sent: Thursday, April 22, 2010 8:14 PM
Subject: Re: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
> In the Netherlands (and most of Europe), you would write one thousand
> million watts as 1.000 megawatts.
>
> The decimal indicator in Europe is a comma.
> For example,
> 1,5 means one and a half
> 1.000.000 means one million.
>
> Sil
> (ex PA3HIL)
Hi Sil, ZL2CIA
In Italy you would write one thousand million watt as 1000 megawatt
or alternatively 1000 MW
In addition the units in Italy are written without plural and to write
megawatts is wrong in Italy but the plural is used in England and USA
In any calculator 1.5 means one and half because the calculators are not
using comma.
In any calculator 1000000. means one million
I thing that the best for everybody should be to write numbars as any
calculator shows.
73" de
i8CVS Domenico
------------------------------
Message: 5
Date: Thu, 22 Apr 2010 17:15:10 -0400
From: davekn4ok@xxx.xxx
Subject: [amsat-bb] Re: Congrats to K7CWQ
To: amsat-bb@xxxxx.xxx
Message-ID: <8CCB078065E8564-5F4-25F8@xxxxxxxxxxxx.xxxxxx.xxx.xxx>
Content-Type: text/plain; charset="us-ascii"
Great Job Loren!!
Dave, kn4ok
Loren, K7CWQ, just received his VUCC award - using a FT-60R and Arrow Sat
ntenna as his station.
CONGRATULATIONS, Loren!
Clint, K6LCS
ttp://www.work-sat.com
______________________________________________
ent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
ot an AMSAT-NA member? Join now to support the amateur satellite program!
ubscription settings: http://amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 6
Date: Thu, 22 Apr 2010 21:31:37 +0000
From: "Mark Hammond N8MH" <marklhammond@xxxxx.xxx>
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
To: "i8cvs" <domenico.i8cvs@xxx.xx>, amsat-bb-bounces@xxxxx.xxxxxxxxx
- ZL2CIA" <zl2cia@xxxxx.xxx>, "Idle-Tyme" <nss@xxx.xxx>
Cc: AMSAT-BB <amsat-bb@xxxxx.xxx>
Message-ID:
<572346919-1271971949-cardhu_decombobulator_blackberry.rim.net-989069903-@xxxx
xx.xxxx.xxxx.xx.xxxxxxxxxx>
Content-Type: text/plain
I think we should all use hexidecimal. Or binary :)
Mark N8MH
Sent via BlackBerry from T-Mobile
-----Original Message-----
From: "i8cvs" <domenico.i8cvs@xxx.xx>
Date: Thu, 22 Apr 2010 23:12:16
To: Sil - ZL2CIA<zl2cia@xxxxx.xxx>; Idle-Tyme<nss@xxx.xxx>
Cc: AMSAT-BB<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some calculations)
----- Original Message -----
From: "Sil - ZL2CIA" <zl2cia@xxxxx.xxx>
To: "Idle-Tyme" <nss@xxx.xxx>
Cc: "i8cvs" <domenico.i8cvs@xxx.xx>; "AMSAT-BB" <amsat-bb@xxxxx.xxx>
Sent: Thursday, April 22, 2010 8:14 PM
Subject: Re: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
> In the Netherlands (and most of Europe), you would write one thousand
> million watts as 1.000 megawatts.
>
> The decimal indicator in Europe is a comma.
> For example,
> 1,5 means one and a half
> 1.000.000 means one million.
>
> Sil
> (ex PA3HIL)
Hi Sil, ZL2CIA
In Italy you would write one thousand million watt as 1000 megawatt
or alternatively 1000 MW
In addition the units in Italy are written without plural and to write
megawatts is wrong in Italy but the plural is used in England and USA
In any calculator 1.5 means one and half because the calculators are not
using comma.
In any calculator 1000000. means one million
I thing that the best for everybody should be to write numbars as any
calculator shows.
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: 7
Date: Thu, 22 Apr 2010 18:03:47 -0400
From: Sebastian <w4as@xxxxxxxxx.xxx>
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
To: AMSAT BB <AMSAT-BB@xxxxx.xxx>
Message-ID: <5BF949B6-044E-4973-8AD5-DE8F67FC6ADA@xxxxxxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
There is also the group of Virtucons who use gagillion, fafillion,
shabolubalu million illion yillion, when describing lasers.
I believe this was first described in a movie with Mr. Myers.
73 de W4AS
On Apr 22, 2010, at 5:31 PM, Mark Hammond N8MH wrote:
> I think we should all use hexidecimal. Or binary :)
>
> Mark N8MH
> Sent via BlackBerry from T-Mobile
>
> -----Original Message-----
> From: "i8cvs" <domenico.i8cvs@xxx.xx>
> Date: Thu, 22 Apr 2010 23:12:16
> To: Sil - ZL2CIA<zl2cia@xxxxx.xxx>; Idle-Tyme<nss@xxx.xxx>
> Cc: AMSAT-BB<amsat-bb@xxxxx.xxx>
> Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some calculations)
>
> ----- Original Message -----
> From: "Sil - ZL2CIA" <zl2cia@xxxxx.xxx>
> To: "Idle-Tyme" <nss@xxx.xxx>
> Cc: "i8cvs" <domenico.i8cvs@xxx.xx>; "AMSAT-BB" <amsat-bb@xxxxx.xxx>
> Sent: Thursday, April 22, 2010 8:14 PM
> Subject: Re: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
> calculations)
>
>> In the Netherlands (and most of Europe), you would write one thousand
>> million watts as 1.000 megawatts.
>>
>> The decimal indicator in Europe is a comma.
>> For example,
>> 1,5 means one and a half
>> 1.000.000 means one million.
------------------------------
Message: 8
Date: Thu, 22 Apr 2010 18:37:56 -0400
From: Michael Tondee <mat_62@xxxxxxxxxxxx.xxx>
Subject: [amsat-bb] : For sale, Yaesu VX-3R HT, ARR RF switched pre
amp ( pre-amp sold)
To: amsat-bb@xxxxx.xxx
Message-ID: <4BD0CFC4.1080201@xxxxxxxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
The pre-amp is sold. The VX-3R is still available.
Thanks to everyone for their interest,
Michael
-------- Original Message --------
Subject: For sale, Yaesu VX-3R HT, ARR RF switched pre amp
Date: Tue, 20 Apr 2010 17:19:26 -0400
From: Michael Tondee <mat_62@xxxxxxxxxxxx.xxx>
To: amsat-bb@xxxxx.xxx
I have for sale a Yaesu VX-3R dual band HT. While it is not full duplex,
it works well as the RX side of a mode J handheld station. I've had it
less than six months if even that long. It has never even been outside
the house and is in like new condition.
Of course box, manual, charger and stock rubber duck are all included.
I'll also throw in a 3ft. long adapter cable that goes from the SMA jack
on the radio to an SO-239 where an external antenna can be used. Price
is $110.00 shipped priority mail in the lower 48.
The pre amp is an Advanced Receiver Research SP432VDG with N
connectors. The RF switching circuit is rated at 25 watts, I actually
only ever used it on a receive only setup with the VX-3R. The pre amp
has been mast mounted in a weatherproof enclosure. ARR says these units
will withstand heat and cold extremes with no problem, they just have to
be mounted in a waterproof enclosure if put outside. As with the HT the
unit has seen very little use and is like new. Price is $85.00 shipped
priority mail in the lower48.
I will accept Paypal or a United States Postal Service money order as
payment. Sorry, no international shipping.
If you are interested, please contact me off list.
Thanks for the bandwidth everyone,
Michael, W4HIJ
------------------------------
Message: 9
Date: Thu, 22 Apr 2010 17:40:12 -0700
From: Clint Bradford <clintbradford@xxx.xxx>
Subject: [amsat-bb] Tickets from Space
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Message-ID: <F27B2C1C-0E97-43CE-B3BC-48ACE3A0FF9B@xxx.xxx>
Content-Type: text/plain; charset=us-ascii
PIPS Technology has developed a license plate recognition system that uses
two cameras on the ground and one mounted on a satellite to catch speeders.
Blog entry at ...
http://tinyurl.com/39c9hlp
Clint, K6LCS
------------------------------
Message: 10
Date: Thu, 22 Apr 2010 17:41:42 -0700 (PDT)
From: John Magliacane <kd2bd@xxxxx.xxx>
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
To: amsat-bb@xxxxx.xxx
Message-ID: <170758.56983.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
--- On Thu, 4/22/10, Mark Hammond N8MH <marklhammond@xxxxx.xxx> wrote:
> I think we should all use
> hexidecimal.? Or binary :)
I tell my electronics students that we can express gain or loss in dB by
taking the log of power ratios and multiplying by 10, or by taking the log
of the voltage or current ratios and multiplying by 20.
If we multiply the log by 16 instead, then the result is expressed in
hexadecibels. :-)
("Hexabels" sounds too much like a made-up word.)
73, de John, KD2BD
--
Visit John on the Web at:
http://kd2bd.ham.org/
------------------------------
Message: 11
Date: Thu, 22 Apr 2010 21:31:49 -0400
From: Bruce Semple <brucesemple@xxxxxxx.xxx>
Subject: [amsat-bb] Re: UHF/VHF Polarization Switch
To: AMSAT-BB@xxxxx.xxx
Message-ID: <0L1B00EKW32XD840@xxxxxxxxx.xxxxxxxxx.xxx>
Content-Type: text/plain; charset=us-ascii; format=flowed
Pete -
I have had one for about 1 1/2 years - on the 70cm antenna.
When the GO-32 9K6 BBS board was up it made the difference between
reliably receiving and not.
(I am working on getting on the AO-51 BBS)
I know S meter readings are all relative -- I usually see at least
+20 when the polarization is correct.
I have roof mounted antennas so I was able to do the modification
without taking the antenna down.
I did shift the antenna mounting position on the boom to account for
the extra length/weight.
During installation checkout - I did have an issue with the
protection diode that was installed across the relay -- I had to replace it.
Other than that -- it has worked fine.
73,
Bruce
WA3SWJ
At 10:48 AM 4/22/2010, you wrote:
>Hello,
>
>I've been asked by a club member if anyone has any experience using an M2
>VHF/UHF Polarization Switch, and what their opinion of it may be. I can't
>seem to find any reviews on field performance, thank you.
>
>73's Pete
>WB2OQQ
>www.massapequanyweather.com
>
>_______________________________________________
>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: 12
Date: Thu, 22 Apr 2010 19:16:47 -0700
From: "D. Craig Fox" <DFox@xxxxxx.xxx>
Subject: [amsat-bb] Re: Tickets from Space
To: "Amsat \(E-mail\)" <amsat-bb@xxxxx.xxx>
Message-ID:
<A8E6E57AFA652D419A823F42AD6ACBDE0359413D@xxxxxxxxx.xxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
Unless California changes Vehicle Code section 40802 (speed traps
prohibited), this wonderfully techno-geeky system will not be lawful for any
excess speed prosecution in California. My 911 was happy to hear that. hihi
Craig
N6RSX
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxxxx
Behalf Of Clint Bradford
Sent: Thursday, April 22, 2010 5:40 PM
To: AMSAT BB
Subject: [amsat-bb] Tickets from Space
PIPS Technology has developed a license plate recognition system that uses
two cameras on the ground and one mounted on a satellite to catch speeders.
Blog entry at ...
http://tinyurl.com/39c9hlp
Clint, K6LCS
_______________________________________________
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
NOTICE: This communication may contain privileged or other confidential
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delete the message and any attachments without copying or disclosing the
contents. Thank you.
------------------------------
Message: 13
Date: Thu, 22 Apr 2010 21:31:14 -0500 (CDT)
From: Stephen Melachrinos <melachri@xxxxxxx.xxx>
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
To: amsat-bb@xxxxx.xxx
Message-ID:
<21072510.571957.1271989874458.JavaMail.root@xxxxxx.xxxxxxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
Nigel -
There are lots of lots of reasons ...
1. All link budgets use a path loss calculation that's also referenced to an
isotropic radiator. If you use antenna gain referenced to a dipole, you'll
have to add back the gain of the dipole (referenced to the isotropic
radiator).
2. It's the standard way of calculating gain for virtually all professionals
in the satellite, radar, deep space, avionics, microwave and many other
fields.
3. Arguably, dBi is less ambiguous that dBd. By definition, an isotropic
reference has the same gain (0 dB) in all directions. A dipole has a
directional pattern, so dBd only makes sense if you also define the
direction. I believe the assumption is gain broadside to the antenna, but
that is still an assumption.
4. If you don't want to actually do link budgets, so you say reason #1 above
is irrelevant, then your only real purpose is to compare two different
antennas. And then the difference is always going to be dB, whether the two
antennas are specified in dBi or dBd. So I still say to use the universal,
unambiguous standard.
5. Finally, and most significantly, your statement "Why would I believe, or
want to use, something I can neither have, use or measure? An isotropic
antenna doesn't exist." is just as applicable to the ideal dipole that is
your reference for dBd as it is to an isotropic radiator. You can't build a
dipole that has zero resistance along its physical length, you can't build a
dipole that has zero interaction with its feedline, and you certainly can't
achieve any placement that perfectly represents the "dipole in free space"
assumption upon which the dBd reference is based.
In summary, there are plenty of reasons whay virtually anyone who builds or
uses antennas for a living, does it in dBi
Steve
W3HF
> Apr 22, 2010 09:15:04 AM, nigel@xxxxx.xxx wrote:
> I guess because it's impossible to build an isotropic radiator and
therefore just as impossible to measure it.
> Why would I believe, or want to use, something I can neither have, use or
measure?
>
> An isotropic antenna doesn't exist.
>
> > In fact, the amateur community is the only place where there is a
fascination with the dipole reference.
------------------------------
Message: 14
Date: Thu, 22 Apr 2010 13:48:49 -0700
From: "LOREN RASMUSSEN" <lorenrasmussen@xxx.xxx>
Subject: [amsat-bb] Satellite VUCC # 194
To: <amsat-bb@xxxxx.xxx>
Message-ID: <SNT131-ds11E534CFD655AB8BFC261ECC080@xxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
It came in the mail today. It took from
November 2009 through February 2010.
About 600 QSOs. FT-60R and an Arrow.
36 states confirmed.
Thank you all that returned cards.
Yeah, I'm jazzed.
73
Loren
k7cwq
CN94
------------------------------
Message: 15
Date: Thu, 22 Apr 2010 23:53:38 +0000 (GMT)
From: "Trevor ." <m5aka@xxxxx.xx.xx>
Subject: [amsat-bb] Deployable Solar Panels on a 1U CubeSat
To: amsat-bb@xxxxx.xxx
Message-ID: <427013.89152.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=utf-8
Interesting presentation by Abhishek Bajpayee on deployable Solar Panels at
http://www.ustream.tv/channel/CubeSatWorkshop/v3
A number of other presentations from the first two days are also available
at this URL
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: 16
Date: Thu, 22 Apr 2010 21:03:37 -0700 (PDT)
From: John Neeley <w6zkh@xxx.xxx>
Subject: [amsat-bb] Re: Satellite VUCC # 194
To: LOREN RASMUSSEN <lorenrasmussen@xxx.xxx>, amsat-bb@xxxxx.xxx
Message-ID: <702522.76869.qm@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
That'll teach you to stand out in a blizzard on the driveway, hi....
Congrat's Loren. Myself I have 118 grids confirmed now, but havent had them
checked, and I got 47 states confirmed. Still need Maine, Nebraska and
Rhode Island on my end for W.A.S.
John W6ZKH
________________________________
From: LOREN RASMUSSEN <lorenrasmussen@xxx.xxx>
To: amsat-bb@xxxxx.xxx
Sent: Thu, April 22, 2010 1:48:49 PM
Subject: [amsat-bb] Satellite VUCC # 194
It came in the mail today. It took from
November 2009 through February 2010.
About 600 QSOs. FT-60R and an Arrow.
36 states confirmed.
Thank you all that returned cards.
Yeah, I'm jazzed.
73
Loren
k7cwq
CN94
_______________________________________________
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: 17
Date: Thu, 22 Apr 2010 22:18:53 -0700
From: "Art McBride" <kc6uqh@xxx.xxx>
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)
To: "'Edward Cole'" <kl7uw@xxxxxxxxx.xxx>, <w3hf@xxxx.xxx>,
<amsat-bb@xxxxx.xxx>
Message-ID: <370E26E2710D4732B82795399A41289F@xxxxxx>
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dBi is used in range calculations because a isotropic antenna has an even
radiating field leaving only distance as a variable when calculating path
loss. After determining the path loss for a given distance, the antenna
gain, transmit power, receiver sensitivity, receiver noise, cable loss, and
connector losses are factored into the equation to give a link budget. With
the excess allocated to fade margin.
ERP calculations are used by regulatory agency's to determine possible
interference.
Art,
KC6UQH
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of Edward Cole
Sent: Thursday, April 22, 2010 8:47 AM
To: w3hf@xxxx.xxxx amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some calculations)
At 02:20 AM 4/22/2010, Stephen Melachrinos wrote:
>Ah, but this focuses on my question: Why is ERP referenced to a
>dipole? Why did someone assume that Arecibo's stated gain of 60 dB
>was dBd and not dBi? I've never seen the gain of a dish antenna used
>in satellite work quoted in dBd. All of the references for
>calculating gain are based on the isotropic reference. And all of
>the usages I have seen (in professional satellite work) use ERP and
>EiRP interchangeably, and the i in EiRP is used to explicitly state
>"referenced to isotropic."
>
>In fact, the amateur community is the only place where there is a
>fascination with the dipole reference.
>
>The dBd specs are useless for any real calculation purposes. Satcom
>engineering is much simpler if everyone quotes isotropic, and all
>commercial/government/military satellite link budgets are based on
>isotropic references.
>
>Steve Melachrinos
>W3HF
>(Professional) Satcom Engineer since 1979
>
>
> > "ERP is about 243 MW" and
> > that comes from the conversion from dBi to dBd.
>_______________________________________________
>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
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In fact the first gain number published over a month ago was 58
dBi. Then I suppose a bunch of hams complained that they didn't
understand isotropic gain so the Arecibo folks kindly converted the
number to 60 dBd. (i.e. unity isotropic gain, dBi=0, is what a true
omni-directional antenna produces in free space)
Does anyone on this reflector know the formula for calculating gain
of a parabolic dish (Yes, I know-I'm asking if you know)? Did you
know that Arecibo dish is spherical and not parabolic? So we can
only use the gain number they provide (BTW the UHF line-feed corrects
for spherical aberration of the dish surface at Arecibo). Arecibo
can track a small amount of angle "because" the dish is
spherical. It is my understanding (might be wrong on this) the
line-feed can adjust for the amount of surface irradiated (which will
change the gain).
The formula normally used in radio astronomy and mw engineering is in
terms of dBi. Most (not all) eme hams use dBi vs dBd.
I am really amazed at this thread on amsat-bb. I thought the
satellite community was more globally oriented (International). The
different convention in expressing decimal numbers (aka using comma
or period) is pretty well known (I thought). US/UK use period and
most EU use comma.
Most antenna analysis sw express gain in dBi
73, Ed - KL7UW, WD2XSH/45
======================================
BP40IQ 500 KHz - 10-GHz www.kl7uw.com
EME: 144-600w, 432-100w, 1296-60w, 3400-fall 2010
DUBUS Magazine USA Rep dubususa@xxxxxxx.xxx
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End of AMSAT-BB Digest, Vol 5, Issue 185
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