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CX2SA > SATDIG 19.08.08 16:00l 816 Lines 25994 Bytes #999 (0) @ WW
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Sent: 080819/1345Z @:CX2SA.LAV.URY.SA #:26959 [Minas] FBB7.00e $:26959_CX2SA
From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. June 2008 meeting of the IARU Administrative Council (Trevor)
2. Re: Re Compass-1 recovery efforts (Alan Cresswell)
3. WG: COMPASS-1 beacon (Mike Rupprecht)
4. TS2000 VS FT847 (Stuart Underwood)
5. Re: TS2000 VS FT847 (Alan P. Biddle)
6. Re: Re Compass-1 recovery efforts (Alan Cresswell)
7. LMR400 or 400UF? (Michael Tondee)
8. Re: LMR400 or 400UF? (Sebastian)
9. TS-2000 sensitivity mod-production years? (Mark L. Hammond)
10. Re: LMR400 or 400UF? (Patrick Domack)
11. Re: TS-2000 sensitivity mod-production years? (Alan Cresswell)
12. Portable from grid DO20 (Ron G. Seiler)
13. Re: LMR400 or 400UF? (i8cvs)
14. Re: COMPASS-1 needs your help (Greg D.)
15. Re: LMR400 or 400UF? (Edward Cole)
16. Re: COMPASS-1 needs your help (Simon (HB9DRV))
----------------------------------------------------------------------
Message: 1
Date: Mon, 18 Aug 2008 19:05:08 +0000 (GMT)
From: Trevor <m5aka(AT)yahoo.co.uk>
Subject: [amsat-bb] June 2008 meeting of the IARU Administrative
Council
To: AMSAT BB <amsat-bb(AT)amsat.org>
Message-ID: <840015.24705.qm(AT)web27202.mail.ukl.yahoo.com>
Content-Type: text/plain; charset=utf-8
The Summary Record of the 24-25 June 2008 meeting of the IARU Administrative
Council is now available.
It can be seen at
http://www.iaru.org/ac-0806min.pdf
The news release describing the meeting was previously distributed and is
available at http://www.iaru.org/rel080626.html
The spectrum requirements document referred to at Agenda Item 10.2 is posted
at http://www.iaru.org/ac-08spec.pdf
The booklet by ON4UN and ON4WW that is referred to in the footnote at the
bottom of page 10 is at
http://www.iaru.org/Eth-operating-EN-iaru-SITE-1july2008.pdf
International Amateur Radio Union (IARU)
http://www.iaru.org/
----
Send instant messages to your online friends http://uk.messenger.yahoo.com
------------------------------
Message: 2
Date: Mon, 18 Aug 2008 20:24:56 -0000
From: "Alan Cresswell" <alancresswell(AT)xtra.co.nz>
Subject: [amsat-bb] Re: Re Compass-1 recovery efforts
To: <amsat-bb(AT)amsat.org>
Message-ID: <000301c90170$7bc039d0$0501010a(AT)Dell1>
Content-Type: text/plain; charset="us-ascii"
Hi Mike,
Compass pass at 2004 UT.
Sent commands at 2008 but only got response from ****13#200#.
Resent commands at 2012 and all were accepted including the beacon test
command but I did not hear any beacon.
Alan
ZL2BX
------------------------------
Message: 3
Date: Mon, 18 Aug 2008 22:38:54 +0200
From: "Mike Rupprecht" <mail(AT)mike-rupprecht.de>
Subject: [amsat-bb] WG: COMPASS-1 beacon
To: "'AMSAT-BB'" <amsat-bb(AT)amsat.org>
Message-ID: <004001c90172$6ec9fac0$4c5df040$(AT)de>
Content-Type: text/plain; charset="iso-8859-1"
Hi all,
the beacon was heard by Robert in Hawaii - very low batteries and the heater
is on.
18.08.2008 20:29UTC FF080008180000210000900001
---------------------------------------------------
Solar Cell Voltage 5.00 V
Solar Panel 6 Cur 50.20 mA
Solar Panel 2 Cur 0.00 mA
Solar Panel 3 Cur 150.59 mA
Solar Panel 4 Cur 50.20 mA
Solar Panel 5 Cur 0.00 mA
EPS Reset Counter 0
Power Level Critical Battery Capacity
Heater Active Battery Heater ON
Power Safe Counter 0
Emergency Mode Counter 0
Battery Voltage 2.82 V
Battery Current 0.00 mA
Battery Temperature 1 ?C
At this point it is very important to switch off the heater to charge the
batteries.
Hopefully we are on the right way...
Thank you for your support!
73, Mike
DK3WN
-----Urspr?ngliche Nachricht-----
Von: Robert Smith [mailto:dukenuke(AT)pixi.com]
Gesendet: Montag, 18. August 2008 22:24
An: Mike Rupprecht
Betreff: Re: [amsat-bb] COMPASS-1 beacon
GOT IT Mike!
Strong signal! 00COMPASSFF080008180000210000900001.
1953Z 08/18/08 at 37 el. east of honolulu.
Unreal that I deleted Sound Forge last nite for a newer version. I will send
AUDIO ASAP.
Respectfully
robert smith NH7WN
Honolulu.
------------------------------
Message: 4
Date: Mon, 18 Aug 2008 14:02:21 -0700 (PDT)
From: Stuart Underwood <w8stu(AT)att.net>
Subject: [amsat-bb] TS2000 VS FT847
To: AMSAT BB <amsat-bb(AT)AMSAT.Org>
Message-ID: <581624.99219.qm(AT)web83815.mail.sp1.yahoo.com>
Content-Type: text/plain; charset=us-ascii
Greetings,
I have a TS2000, but it has birdies in the Sat. portions of the band. I was
also thinking about getting a FT847... Does the 847 have birdies like the
2000? Does the 847 have better sensitivity on VHF/UHF? The 2000 I have to
run the pre amps all of the time. Even with repeater work. Thanks in
advance. 73, Stuart W8STU
------------------------------
Message: 5
Date: Mon, 18 Aug 2008 16:30:47 -0500
From: "Alan P. Biddle" <APBIDDLE(AT)UNITED.NET>
Subject: [amsat-bb] Re: TS2000 VS FT847
To: "'Stuart Underwood'" <w8stu(AT)att.net>, "'AMSAT BB'"
<amsat-bb(AT)amsat.org>
Message-ID: <659EAB3C258F42D29B2CD82DC2237A39(AT)WA4SCA>
Content-Type: text/plain; charset="us-ascii"
Stuart,
I am assuming you mean the horrible birdie on 436.795 which makes working
AO-27 and SO-50 tricky to impossible? No, there is nothing like that in the
FT-847, though it has a few low level birdies. They can often be reduced by
making certain that the grounding screws for the PC boards are tight, and
that the insulating mask is scraped clear.
The early TS2000 had VHF/UHF sensitivity issues. There is a fix for that
available, and recent production runs have had that fix included. However,
needing to run the preamps with local repeaters would make me wonder if
there is a problem somewhere. The FT-847 works fine without the preamps for
all but weak signal and satellite ops.
Alan
WA4SCA
------------------------------
Message: 6
Date: Mon, 18 Aug 2008 21:57:22 -0000
From: "Alan Cresswell" <alancresswell(AT)xtra.co.nz>
Subject: [amsat-bb] Re: Re Compass-1 recovery efforts
To: <amsat-bb(AT)amsat.org>
Message-ID: <000701c9017d$65849fa0$0501010a(AT)Dell1>
Content-Type: text/plain; charset="us-ascii"
Hi Mike,
Compass pass at 2139 UT.
Sent commands at 2142 and all were accepted including the beacon test
command but once again I did not hear any beacon. I have the command wave
file if you want it but will have to send it later in the day as I am away
for a couple of hours. Good to hear the beacon was heard in Hawaii.
Alan
ZL2BX
------------------------------
Message: 7
Date: Mon, 18 Aug 2008 19:05:11 -0400
From: "Michael Tondee" <mat_62(AT)netcommander.com>
Subject: [amsat-bb] LMR400 or 400UF?
To: <amsat-bb(AT)amsat.org>
Message-ID: <001101c90186$de7d9f70$6500a8c0(AT)w4hij1>
Content-Type: text/plain; charset="iso-8859-1"
I need to rework my 70cm antenna system and was thinking about going with LMR
400. I have about a 40 foot run. Is there any real advantage to using the
ultra flex for the entire run or can I get by with a short section of the UF
between the preamp and antenna to accomodate the rotor turning? How about just
using a short section of RG8U there instead of the LMR400UF? I'm trying to do
this on a budget.
Tnx and 73,
Michael, W4HIJ
------------------------------
Message: 8
Date: Mon, 18 Aug 2008 20:36:44 -0400
From: Sebastian <w4as(AT)bellsouth.net>
Subject: [amsat-bb] Re: LMR400 or 400UF?
To: AMSAT BB <amsat-bb(AT)amsat.org>
Message-ID: <F64B3D18-0828-46FA-B62C-5096548B6D3E(AT)bellsouth.net>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
I have no affiliation with this company, but I was very surprised by
their prices, and very happy with their coax:
http://www.jefatech.com/product/ll400
Even if you do go with the 'real' LMR400, I think you'll have better
luck than with RG8U.
73 de W4AS
Sebastian
On Aug 18, 2008, at 7:05 PM, Michael Tondee wrote:
> I need to rework my 70cm antenna system and was thinking about going
> with LMR 400. I have about a 40 foot run. Is there any real
> advantage to using the ultra flex for the entire run or can I get by
> with a short section of the UF between the preamp and antenna to
> accomodate the rotor turning? How about just using a short section
> of RG8U there instead of the LMR400UF? I'm trying to do this on a
> budget.
> Tnx and 73,
> Michael, W4HIJ
> _______________________________________________
> 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: 9
Date: Mon, 18 Aug 2008 20:45:02 -0400
From: "Mark L. Hammond" <n8mh(AT)embarqmail.com>
Subject: [amsat-bb] TS-2000 sensitivity mod-production years?
To: amsat-bb(AT)AMSAT.Org
Message-ID: <8E.CC.21033.E871AA84(AT)smtp07.embarq.synacor.com>
Content-Type: text/plain; charset="us-ascii"
Hello all,
There has been a few posts lately about the "sensitivity mod" for the TS-2000
radio--but it seems like there was a point when Kenwood may have "fixed" the
issue.
Does anybody know the production year, or serial number ranges, that apply to
radios needing the "improvement"? I've always thought mine was a bit deaf,
esp. on 2M.
I bought my TS-2000X in early 2004...my serial number starts with 509.
(I just performed the mod, but I'm not sure I can see an improvement--but
haven't been able to test it on a bird yet).
Thanks!
Mark L. Hammond [N8MH]
------------------------------
Message: 10
Date: Mon, 18 Aug 2008 21:16:20 -0400
From: Patrick Domack <patrickdk(AT)patrickdk.com>
Subject: [amsat-bb] Re: LMR400 or 400UF?
To: amsat-bb(AT)amsat.org
Message-ID: <20080818211620.b3mgpemxygoowgcc(AT)tenchi.patrickdk.com>
Content-Type: text/plain; charset=ISO-8859-1; DelSp="Yes";
format="flowed"
Between your antenna and the preamp is where you want your best coax
at, cause every bit of loss you have there, is lost.
Once it's past the preamp, it will give you good gain, so then it's
just how paranoid you are, as to how much loss you are willing to give
up, to get it into your shack.
If your preamp has a noise level of like 1db, you should be able to
safely loose 1db in coax from your preamp to your shack, and at
40feet, your talking about rg8, maybe mini8 (1.2db I believe).
I'm one of the paranoid people, and normally keep my losses <1db, and
most of them are <.5 db
Quoting Michael Tondee <mat_62(AT)netcommander.com>:
> I need to rework my 70cm antenna system and was thinking about going
> with LMR 400. I have about a 40 foot run. Is there any real
> advantage to using the ultra flex for the entire run or can I get by
> with a short section of the UF between the preamp and antenna to
> accomodate the rotor turning? How about just using a short section
> of RG8U there instead of the LMR400UF? I'm trying to do this on a
> budget.
> Tnx and 73,
> Michael, W4HIJ
> _______________________________________________
> 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: 11
Date: Tue, 19 Aug 2008 02:39:50 -0000
From: "Alan Cresswell" <alancresswell(AT)xtra.co.nz>
Subject: [amsat-bb] Re: TS-2000 sensitivity mod-production years?
To: <amsat-bb(AT)amsat.org>
Message-ID: <001901c901a4$daf31d80$0501010a(AT)Dell1>
Content-Type: text/plain; charset="US-ASCII"
Hi Mark,
I can't answer your question directly but I have a TS-2000X Serial 811...
and it certainly does not lack sensitivity. I also have a recent IC-910H
which has the same spec and I can not separate them in terms of sensitivity
under a wide range of conditions. I much prefer the TS-2000 for a variety
of other reasons but use the 910 on SO-50. (No prizes for guessing why!)
Alan
ZL2BX.
-----Original Message-----
From: amsat-bb-bounces(AT)amsat.org [mailto:amsat-bb-bounces(AT)amsat.org] On
Behalf Of Mark L. Hammond
Sent: Tuesday, 19 August 2008 00:45
To: amsat-bb(AT)amsat.org
Subject: [amsat-bb] TS-2000 sensitivity mod-production years?
Hello all,
There has been a few posts lately about the "sensitivity mod" for the
TS-2000 radio--but it seems like there was a point when Kenwood may have
"fixed" the issue.
Does anybody know the production year, or serial number ranges, that apply
to radios needing the "improvement"? I've always thought mine was a bit
deaf, esp. on 2M.
I bought my TS-2000X in early 2004...my serial number starts with 509.
(I just performed the mod, but I'm not sure I can see an improvement--but
haven't been able to test it on a bird yet).
Thanks!
Mark L. Hammond [N8MH]
_______________________________________________
Sent via AMSAT-BB(AT)amsat.org. Opinions expressed are those of the author.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 12
Date: Mon, 18 Aug 2008 19:47:37 -0700
From: "Ron G. Seiler" <rgseiler(AT)shaw.ca>
Subject: [amsat-bb] Portable from grid DO20
To: <amsat-bb(AT)amsat.org>
Message-ID: <003501c901a5$f0d43340$7602a8c0(AT)CENTRAL>
Content-Type: text/plain; charset="us-ascii"
Hello All,
I will attempt to work AO-51 and SO-50 from DO20 on August 20-22 UTC with a
5 watt handheld into an Arrow antenna. This grid hasn't been active for a
number of years.
73,
Ron VA7VW
http://www.va7vw.ca <http://www.va7vw.ca/>
------------------------------
Message: 13
Date: Tue, 19 Aug 2008 05:56:18 +0200
From: "i8cvs" <domenico.i8cvs(AT)tin.it>
Subject: [amsat-bb] Re: LMR400 or 400UF?
To: "Michael Tondee" <mat_62(AT)netcommander.com>, "AMSAT-BB"
<amsat-bb(AT)amsat.org>
Message-ID: <004b01c901af$898a0c00$0201a8c0(AT)tin.it>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "Michael Tondee" <mat_62(AT)netcommander.com>
To: <amsat-bb(AT)amsat.org>
Sent: Tuesday, August 19, 2008 1:05 AM
Subject: [amsat-bb] LMR400 or 400UF?
> I need to rework my 70cm antenna system and was thinking about going with
LMR 400. I have about a 40 foot run. Is there any real advantage to using
the ultra flex for the entire run or can I get by with a short section of
the UF between the preamp and antenna to accomodate the rotor turning? How
about just using a short section of RG8U there instead of the LMR400UF? I'm
trying to do this on a budget.
> Tnx and 73,
> Michael, W4HIJ
> _______________________________________________
Hi Michael, W4HIJ
The attenuation in dB of any transmission line connected between the antenna
and the preamplifier add directly to the Noise Figure NF of the preamplifier
and the power of the signal lost between the antenna and the preamplifier
cannot be recovered.
The attenuation of RG8U at 420 MHz is 4.8 dB /100 ft while the attenuation
of LMR400UF at 400 MHz is 3 dB / 100 ft
You don't mention how many ft of cable you plan to use between the antenna
and the preamplifier wich is antenna mounted by the way it is obvious that
the LMR400UF has less losses in comparison of the RG8U and it is preferred.
Suppose that the run of cable between the antenna and the preamplifier is
only 10 ft and the Noise Figure of your 70 cm preamplifier is NF= 0.5 dB
Using RG8U the NF of your preamplifier is like to be 0.98 dB while using
LMR400UF the NF is like to be 0.8 dB
About the real advantage of using the ultra flex LMR400UF instead of LMR400
for the entire run of 40 ft between the output of the preamplifier and the
RX input from the receiving point of view there is not any advantage because
the loss for 40 ft of LMR400UF is 1.2 dB while the loss of 40 ft of LMR 400
is 1.08 dB
By the way the gain of any good preamplifier for 70 is in the order of 20 dB
minimum so that the loss of 1.2 dB for the entire run of LMR400UF versus
1.08 dB for the entire run of LMR400 subtracts directly to the gain of the
preamplifier but the loss of gain is so low in both situations that the
overall Noise Figure of the receiving system is not deteriorated using one
cable or the other one as calculation shows.
>From the transmission point of view thinks are much different because the
full run of 40 ft is used as well for TXing so that the LMR400 with only
1.08 dB attenuation versus 1.2 dB for the LMR400UF is preferred.
In conclusion all considering for RX/TX conditions I would use:
LMR400UF between the antenna and the preamplifier and LMR400
between the preamplifier and RX/TX
For detailed information on this matter and how to perform calculations I
suggest to read the article:
"Receiver Noise Figure Sensitivity and Dinamic Range ,what the Numbar mean"
by James R. Fisk, W1DTY Ham Radio Magazine october 1975
Since the above article is very old and difficult to find I cand send a
zipped copy of it to everyone is interested.
Best 73" de
i8CVS Domenico
------------------------------
Message: 14
Date: Mon, 18 Aug 2008 22:15:07 -0700
From: "Greg D." <ko6th_greg(AT)hotmail.com>
Subject: [amsat-bb] Re: COMPASS-1 needs your help
To: Mike Rupprecht <mail(AT)mike-rupprecht.de>, "'AMSAT-BB'"
<amsat-bb(AT)amsat.org>
Message-ID: <BLU133-W965EEA2F3FBC1F1C9E9F6A9690(AT)phx.gbl>
Content-Type: text/plain; charset="iso-8859-1"
Hi Mike,
Just finished another pass where COMPASS came out of eclipse mid-pass. I
tried several ****14#200# sequences, from sunlight to LOS. No beeps heard,
however.
Greg KO6TH
----------------------------------------
> From: mail(AT)mike-rupprecht.de
> To: amsat-bb(AT)amsat.org
> Date: Sun, 17 Aug 2008 11:12:19 +0200
> Subject: [amsat-bb] Re: COMPASS-1 needs your help
>
> Hi all,
>
> Now we received 2 successfully contacts with COMPASS from Alan (ZL2BX) and
> Sion (9W2QC).
> On both passes was COMPASS in full sunlight.
>
> The most important commando is ****#14#200# to switch the heater off.
>
> Thank you so much for your effort and time. And please, continue to trying
> and help us to recover COMPASS.
>
> Again, thank you very much for your help.
>
> 73, Mike
> DK3WN
>
>
>
>
> -----Urspr?ngliche Nachricht-----
> Von: amsat-bb-bounces(AT)amsat.org [mailto:amsat-bb-bounces(AT)amsat.org] Im
> Auftrag von Alan Cresswell
> Gesendet: Samstag, 16. August 2008 23:22
> An: 'AMSAT-BB'
> Betreff: [amsat-bb] Re: COMPASS-1 needs your help
>
> Mike,
>
> I have just sent the tone sequences to compass and received a very short
> beep tone immediately after each command on the downlink. The tone has a
> slight change of pitch for its duration. The equipment used was a TS-2000
> with the tones in memory and the tone duration set to "SLOW" (100ms tone,
> 100ms mute).
> Compass pass at 2102 UT and max el 54 deg.
>
> Alan
> ZL2BX
>
>
> -----Original Message-----
> From: amsat-bb-bounces(AT)amsat.org [mailto:amsat-bb-bounces(AT)amsat.org]
On
> Behalf Of Mike Rupprecht
> Sent: Saturday, 16 August 2008 13:55
> To: 'AMSAT-BB'
> Cc: Jakob.Schab(AT)gmx.de; johannes.piepenbrock(AT)gmx.de;
> felix.koenig(AT)alumni.fh-aachen.de; 'Artur Scholz'; kev(AT)kunz.biz
> Subject: [amsat-bb] COMPASS-1 needs your help
>
> Hi all,
>
> The recent events are dramatically. Our two ground stations are almost
> inoperable.
>
> A few days ago however, a hard-reset of the satellite had occurred, which
> brought the satellite back into the following vicious circle: Once the
> heater is being switched on, the battery power drops drastically, which
> causes another hard-reset. This goes on and on. The only chance to recover
> the satellite is to avoid the activation of the heater. This can be done by
> adjusting threshold values.
>
> Since these values are reset after each hard-reset, we would need to send
> them again and again, until the satellite is in a stable condition
> (batteries charging), where no reset occurs.
>
> Thus, if you would like to support this recovery phase and have the right
> equipment to do so, please upload the following DTMF tones to COMPASS-1
> (simply from loudspeaker via microphone)
>
> THRESHOLD ADJUSTMENT (to do after every hard reset)
>
> ****14#200# heater off to -55 degr THIS
> IS THE VERY IMPORTANT COMMAND
>
>
>
> ****13#200# heater on to -55 degr
> ****16#170# critical batt threshold to 3.3V
> ****15#255# low batt threshold to max -> charge batteries
>
> The commands consist of 4 stars, two numbers, a hash, 3 numbers, and a hash.
>
>
> If COMPASS receive this sequence successfully you can hear a short
> confirmation beep.
>
>
>
> There is an good and free DTMF dialer to download here:
>
> http://www.polar-electric.com/DTMF/Index.html#Encoder
>
>
>
> Uplink: 145.980 MHz FM
>
> Downlink: 437.275 MHz CW
>
>
>
> If you have any questions, please ask me. Thank you very much in advance !!!
>
>
> We appreciate your support!! On behalf the COMPASS-team
>
> 73, Mike DK3WN
>
> For more information see : http://www.raumfahrt.fh-aachen.de/news.htm
>
>
>
>
>
>
>
>
>
> _______________________________________________
> 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
>
> _______________________________________________
> 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
>
>
> _______________________________________________
> 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
>
>
> _______________________________________________
> 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
_________________________________________________________________
Get ideas on sharing photos from people like you. Find new ways to share.
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Gallery_082008
------------------------------
Message: 15
Date: Mon, 18 Aug 2008 22:18:48 -0800
From: Edward Cole <kl7uw(AT)acsalaska.net>
Subject: [amsat-bb] Re: LMR400 or 400UF?
To: Patrick Domack <patrickdk(AT)patrickdk.com>, amsat-bb(AT)amsat.org
Message-ID: <200808190618.m7J6InhD056801(AT)iris.acsalaska.net>
Content-Type: text/plain; charset="us-ascii"; format=flowed
At 05:16 PM 8/18/2008, Patrick Domack wrote:
>Between your antenna and the preamp is where you want your best coax
>at, cause every bit of loss you have there, is lost.
>
>Once it's past the preamp, it will give you good gain, so then it's
>just how paranoid you are, as to how much loss you are willing to give
>up, to get it into your shack.
>
>If your preamp has a noise level of like 1db, you should be able to
>safely loose 1db in coax from your preamp to your shack, and at
>40feet, your talking about rg8, maybe mini8 (1.2db I believe).
>
>I'm one of the paranoid people, and normally keep my losses <1db, and
>most of them are <.5 db
>
>Quoting Michael Tondee <mat_62(AT)netcommander.com>:
>
> > I need to rework my 70cm antenna system and was thinking about going
> > with LMR 400. I have about a 40 foot run. Is there any real
> > advantage to using the ultra flex for the entire run or can I get by
> > with a short section of the UF between the preamp and antenna to
> > accomodate the rotor turning? How about just using a short section
> > of RG8U there instead of the LMR400UF? I'm trying to do this on a
> > budget.
> > Tnx and 73,
> > Michael, W4HIJ
Michael,
Assuming your cable is not long from the antenna to the preamp it
will not matter that much.
I calculated the loss in an 8-foot run of LMR-400 vs LMR-400UF. The
former shows 0.2 dB loss vs 0.3 dB loss for the flex cable.
I am running LMR-400UF from my terrestrial 432 and 222 antennas to
the preamp. I then run RG-8/x or also called mini-8 from the output
of the preamp to the radio. The flex is better suited for flexing
around the rotator. You can use RG-8/U instead of the mini-8 equally
well. But do use at least LMR-400UF in front to your preamps to get
the best low-noise performance.
If you are sharing the line from the house for transmitting the run
LMR-400 up to the preamps and coax relays.
*****************************************************
73, Ed - KL7UW BP40iq, 6m - 3cm
144-EME: FT-847, mgf-1801, 4x-xp20, 185w
http://www.kl7uw.com AK VHF-Up Group
NA Rep. for DUBUS: dubususa(AT)hotmail.com
*****************************************************
------------------------------
Message: 16
Date: Tue, 19 Aug 2008 10:52:12 +0200
From: "Simon \(HB9DRV\)" <simon(AT)hb9drv.ch>
Subject: [amsat-bb] Re: COMPASS-1 needs your help
To: "'AMSAT-BB'" <amsat-bb(AT)amsat.org>
Message-ID: <2387280C556F48D5BE7994BD7408407B(AT)doubletrouble>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Nothing heard here a few minutes ago, satellite in the sun all the way. I
was just listening on the CW downlink.
I normally hear all CW beacons.
Simon Brown, HB9DRV
www.ham-radio-deluxe.com
----- Original Message -----
From: "Greg D." <ko6th_greg(AT)hotmail.com>
Just finished another pass where COMPASS came out of eclipse mid-pass. I
tried several ****14#200# sequences, from sunlight to LOS. No beeps heard,
however.
------------------------------
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End of AMSAT-BB Digest, Vol 3, Issue 422
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