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CX2SA > SATDIG 10.03.11 22:16l 731 Lines 23649 Bytes #999 (0) @ WW
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From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. Re: IC-821H Frontend Overload? (Dee)
2. AO-51 back on (Andrew Glasbrenner)
3. 145.825 MHz satellite (Andrew Rich)
4. Re: 145.825 MHz satellite (Andrew Rich)
5. Re: 145.825 MHz satellite (Gordon JC Pearce)
6. Re: 145.825 MHz satellite (Ron Overdrive)
7. for sale (Dads)
8. Re: 145.825 MHz satellite (Gordon JC Pearce)
9. Re: 145.825 MHz satellite (Gordon JC Pearce)
10. Practical Wireless - FUNcube Dongle Article (Trevor .)
11. Re: 145.825 MHz satellite (Jeremy Bomkamp)
12. pots for Yaseu G5400 rotors (n4csitwo@xxxxxxxxx.xxxx
13. Re: pots for Yaseu G5400 rotors (John Price)
14. Re: IC-821H Frontend Overload? (i8cvs)
15. Fwd: [PNWVHFS] FS: Yaesu FT-736R with 222 and 1296 modules
(Bob- W7LRD)
16. Re: IC-821H Frontend Overload? (Andrew Rich)
----------------------------------------------------------------------
Message: 1
Date: Wed, 09 Mar 2011 15:57:07 -0500
From: Dee <morsesat@xxxxxxxxx.xxx>
Subject: [amsat-bb] Re: IC-821H Frontend Overload?
To: "'Mark L. Hammond'" <marklhammond@xxxxx.xxx>, "'Paul Delaney -
K6HR'" <paul.hamradio@xxxxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <C4668AD490D94BDB8321F9F95D0447CE@xxxxxxxx>
Content-Type: text/plain; charset=us-ascii
There is no 24db gain 432 preamp from ARR-They list as a 1 db difference.
You should go for the gasfet as the noise figure will be the difference. I
used one on my 821H for many years-no probs encountered.
73,
Dee,
NB2F
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of Mark L. Hammond
Sent: Wednesday, March 09, 2011 1:28 PM
To: Paul Delaney - K6HR
Cc: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Re: IC-821H Frontend Overload?
It's all about noise figure....I say get the AR2 SP432VDG 24db! If
the front end is "too hot" you can use crummy coax to attenuate the signal
;)
Does the 821H have a preamp that you could turn off if necessary?
Probably won't be necessary, but just in case...
Mark N8MH
On Wed, Mar 9, 2011 at 1:11 PM, Paul Delaney - K6HR
<paul.hamradio@xxxxxxx.xxx> wrote:
> I'm setting up for satellite operation and considering the AR2 SP432VDG
24db preamp. A friend suggests this will likely overload the frontend of the
radio (an 821H) The antennas are M2 eggbeaters. Would the SP432VDA 15db be a
better choice?
>
> Can anyone using these preamps give me some feedback on the 15db vs. 24db
preamps and which might be the best way to go considering the radio and
antennas I have?
>
> Paul Delaney
> paul.hamradio@xxxxxxx.xxx
> http://k6hr.dyndns.org:8080
> _______________________________________________
> 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
>
--
Mark L. Hammond [N8MH]
_______________________________________________
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: 2
Date: Wed, 09 Mar 2011 16:33:41 -0500
From: Andrew Glasbrenner <glasbrenner@xxxxxxxxxx.xxx>
Subject: [amsat-bb] AO-51 back on
To: "Mark L. Hammond" <marklhammond@xxxxx.xxx>
Cc: Amsat - BBs <amsat-bb@xxxxx.xxx>
Message-ID: <4D77F235.6020003@xxxxxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Back to normal as of 2055Z or so. Reports to oscar.dcarr.org are
appreciated.
73, Drew KO4MA
AMSAT-NA VP Operations
On 3/9/2011 11:16 AM, Mark L. Hammond wrote:
> Hi All,
>
> We are receiving and reading multiple reports that AO-51 is OFF, since
> about 1400 utc today.
>
> Additional reports will be appreciated, especially to note if the
> 435.150 transmitter is active or not; if ON, it should be in 9k6
> packet mode.
>
> http://oscar.dcarr.org/
>
> It will be a few more hours (around 2100utc) before the bird is in the
> footprint of a command station, so we'll hope for the best (a quick
> reset after a voltage trip).
>
> 73,
>
------------------------------
Message: 3
Date: Thu, 10 Mar 2011 08:12:34 +1000
From: "Andrew Rich" <vk4tec@xxxxxxxxxxxxx.xxx>
Subject: [amsat-bb] 145.825 MHz satellite
To: <amsat-bb@xxxxx.xxx>
Message-ID: <8AC9C11F00FF4D229CEC0E592E91F4CC@xxxxxxxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hello
I am hearing another satellite on 145.825 MHz
Sounds like some sort of PSK
Ideas ?
- Andrew -
------------------------------
Message: 4
Date: Thu, 10 Mar 2011 08:15:33 +1000
From: "Andrew Rich" <vk4tec@xxxxxxxxxxxxx.xxx>
Subject: [amsat-bb] Re: 145.825 MHz satellite
To: "Andrew Rich" <vk4tec@xxxxxxxxxxxxx.xxx>, <amsat-bb@xxxxx.xxx>
Message-ID: <0C5529CA9485474193B293075D4C502B@xxxxxxxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Must be UO-11 ?
----- Original Message -----
From: Andrew Rich
To: amsat-bb@xxxxx.xxx
Sent: Thursday, March 10, 2011 8:12 AM
Subject: 145.825 MHz satellite
Hello
I am hearing another satellite on 145.825 MHz
Sounds like some sort of PSK
Ideas ?
- Andrew -
------------------------------
Message: 5
Date: Wed, 09 Mar 2011 22:28:25 +0000
From: Gordon JC Pearce <gordonjcp@xxxx.xxx>
Subject: [amsat-bb] Re: 145.825 MHz satellite
To: amsat-bb@xxxxx.xxx
Message-ID: <1299709705.3556.2.camel@xxxxxxxxx.xxxxxxxxxxx>
Content-Type: text/plain; charset="UTF-8"
On Thu, 2011-03-10 at 08:15 +1000, Andrew Rich wrote:
> Must be UO-11 ?
>
Check the timings. UO-11 has a distinctive
bleebleeeebleeeebleeeebleeeep AFSK tone, a bit like an old BBC Micro
loading from tape. Nothing else up there sounds like it. It's *really*
strong, too - I could get it driving through a motorway tunnel in
Glasgow where I can't hear the local repeater ;-)
Gordon MM0YEQ
------------------------------
Message: 6
Date: Wed, 9 Mar 2011 17:33:12 -0500
From: Ron Overdrive <ronoverdrive@xxxxxxxx.xxx>
Subject: [amsat-bb] Re: 145.825 MHz satellite
To: Gordon JC Pearce <gordonjcp@xxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID:
<AANLkTikcBxqBdgKGSH4knr62cdW1uPAg-FnHdDLXmnJs@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Make a recording of it and share.
~73, AC2RF Ron
On Wed, Mar 9, 2011 at 5:28 PM, Gordon JC Pearce <gordonjcp@xxxx.xxx> wrote:
> On Thu, 2011-03-10 at 08:15 +1000, Andrew Rich wrote:
> > Must be UO-11 ?
> >
>
> Check the timings. UO-11 has a distinctive
> bleebleeeebleeeebleeeebleeeep AFSK tone, a bit like an old BBC Micro
> loading from tape. Nothing else up there sounds like it. It's *really*
> strong, too - I could get it driving through a motorway tunnel in
> Glasgow where I can't hear the local repeater ;-)
>
> Gordon MM0YEQ
>
> _______________________________________________
> 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: Wed, 9 Mar 2011 16:47:52 -0600
From: "Dads" <w0sat@xxx.xxx>
Subject: [amsat-bb] for sale
To: <amsat-bb@xxxxx.xxx>
Message-ID: <SNT125-DS21BB433A88E2FC673007D7E4C90@xxx.xxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Hi: I,m trying to help a fellow ham with health problems.
He has a real nice Kenwood TS-2000 like new.
It has very low hours on it.
The price is $900.00 firm
w0sat@xxx.xxx
Jerry w0sat
------------------------------
Message: 8
Date: Wed, 09 Mar 2011 22:51:16 +0000
From: Gordon JC Pearce <gordonjcp@xxxx.xxx>
Subject: [amsat-bb] Re: 145.825 MHz satellite
To: amsat-bb@xxxxx.xxx
Message-ID: <1299711076.3556.5.camel@xxxxxxxxx.xxxxxxxxxxx>
Content-Type: text/plain; charset="UTF-8"
On Wed, 2011-03-09 at 17:33 -0500, Ron Overdrive wrote:
> Make a recording of it and share.
>
> ~73, AC2RF Ron
>
I never hear the damn thing when I'm in the house, only when I'm in the
van!
I heard UO-11 the weekend before last, heading up through the Cairngorms
national park, I heard it earlier in the week bimbling around between
customer sides, never heard so much as a chirp when I was actually at
home.
Gordon MM0YEQ
------------------------------
Message: 9
Date: Wed, 09 Mar 2011 22:58:34 +0000
From: Gordon JC Pearce <gordonjcp@xxxx.xxx>
Subject: [amsat-bb] Re: 145.825 MHz satellite
To: amsat-bb@xxxxx.xxx
Message-ID: <1299711514.3556.7.camel@xxxxxxxxx.xxxxxxxxxxx>
Content-Type: text/plain; charset="UTF-8"
On Wed, 2011-03-09 at 17:33 -0500, Ron Overdrive wrote:
> Make a recording of it and share.
Actually, I've found an old recording I made:
http://www.gjcp.net/~gordonjcp/uo11.ogg
Quite noisy, but you get the idea.
Gordon MM0YEQ
------------------------------
Message: 10
Date: Wed, 9 Mar 2011 23:09:14 +0000 (GMT)
From: "Trevor ." <m5aka@xxxxx.xx.xx>
Subject: [amsat-bb] Practical Wireless - FUNcube Dongle Article
To: amsat-bb@xxxxx.xxx
Message-ID: <519510.71300.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
The April edition of Practical Wireless magazine has a special treat for
all satellite enthusiasts and VHF/UHF listeners - a two page article on the
AMSAT-UK FUNcube Dongle radio
The FUNcube Dongle (FCD) Software Defined Radio (SDR) was developed as part
of the AMSAT-UK FUNcube satellite project.
It plugs into the USB port of your PC and although little bigger than a
memory stick covers the range 64 - 1700MHz (Note: external antenna
required). The FCD costs about ?125 and a proportion of the price goes to
support AMSAT-UK's FUNcube satellite. So far over 500 have been sold around
the world.
David Dix G8LZE bought his FCD in January from the second batch to be
produced. He must have been quick off the mark as they all sold out in under
a minute of going on sale!
Since then David has been putting the FCD through its paces. His well
written PW article gives an overview of CubeSats and describes the results
he obtained with his 1/4 wave 70cm Ground Plane antenna and the free WRplus
software.
As usual PW is packed full of first class radio articles. In this issue Data
Modes columist Mike Richards G4WNC deals with ALE, while Chris Lorek G4HCL,
in his Emerging Technology column, shows how once again Amateur Radio work
is proving its valuable worth to the emerging future of radio communications.
Practical Wireless magazine is on sale now from UK High Street newsagents
such as W.H.Smith.
Postal copies can be purchased using a Debit or Credit card by ringing
+44 (0)1202 659910 Monday - Thursday 8.30am - 4.00pm.
Yearly subscriptions to PW are available from
http://www.mysubcare.com/magazinestore.asp?curpage=3
PW Publishing
http://www.pwpublishing.ltd.uk/
Free WRplus SDR Software by Alberto di Bene I2PHD
http://www.wrplus.altervista.org/
You can join the FUNcube Yahoo Group at
http://groups.yahoo.com/group/FUNcube/
----
73 Trevor M5AKA
------------------------------
Message: 11
Date: Wed, 9 Mar 2011 16:00:18 -0800 (PST)
From: Jeremy Bomkamp <wa113y3s@xxxxx.xxx>
Subject: [amsat-bb] Re: 145.825 MHz satellite
To: amsat-bb@xxxxx.xxx
Message-ID: <590185.42251.qm@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
One other than the digipeaters on the ISS and NO-44
------------------------------
Message: 12
Date: Wed, 9 Mar 2011 19:12:37 -0500
From: <n4csitwo@xxxxxxxxx.xxx>
Subject: [amsat-bb] pots for Yaseu G5400 rotors
To: <amsat-bb@xxxxx.xxx>
Message-ID: <8B120CEE99A84DB9AC435316AB7D9E27@xxx>
Content-Type: text/plain; charset="iso-8859-1"
Can anyone recommend a good source for the pots that go into the Yaseu G5400
rotors?
Dave, AA4KN
------------------------------
Message: 13
Date: Wed, 9 Mar 2011 20:00:37 -0500
From: John Price <n4qwf1@xxxxx.xxx>
Subject: [amsat-bb] Re: pots for Yaseu G5400 rotors
To: n4csitwo@xxxxxxxxx.xxxx amsat-bb@xxxxx.xxx
Message-ID:
<AANLkTin39uwzoZaRaY+RB1c9kq7gdZ2q4hJtsyjK-mBw@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
This should be what you need. I bought 4 from them about two years ago.
Parts Department (Manuals, Parts 8 am - 4 pm PST):
1-714-827-7600 parts department
(562) 404-2700
(562) 404-4828 FAX
Email : yaesuparts@xxxxxxxx.xxx
http://www.yaesu.com/amateur/techsupport.html
500K in rotor S8(B)101823
Pot in control box Q9000404
73's << John
On Wed, Mar 9, 2011 at 7:12 PM, <n4csitwo@xxxxxxxxx.xxx> wrote:
> Can anyone recommend a good source for the pots that go into the Yaseu
> G5400 rotors?
>
> Dave, AA4KN
> _______________________________________________
> 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
>
--
N4QWF Amateur Radio Operator
AO-7,AO-27,FO-29,SO-50,AO-51,VO-52,ISS
Email N4QWF@xxxxx.xxx
Formerly KC4AHW VK3FEZ
Amsat Member #27845
DXCC #33,478
VUCC SAT #135
WAS SAT #296
51 on AO-51 #13
LON -79.256 LAT 37.459 Grid FM07il
>From the Foothills of the Blueridge
*Life should not be a journey to the grave with the intention of arriving
safely in a pretty and well preserved body, but rather to skid in broadside,
thoroughly used up, totally worn out, and loudly proclaiming - "WOW, What a
ride!"
------------------------------
Message: 14
Date: Thu, 10 Mar 2011 19:01:56 +0100
From: "i8cvs" <domenico.i8cvs@xxx.xx>
Subject: [amsat-bb] Re: IC-821H Frontend Overload?
To: "Paul Delaney - K6HR" <paul.hamradio@xxxxxxx.xxx>, "Amsat - BBs"
<amsat-bb@xxxxx.xxx>
Message-ID: <000801cbdf4d$3f059f40$0401a8c0@xxxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Paul, K6HR
The SSB and CW sensitivity of an IC 821H in 70 cm is less than 0.11uV
for a Signal to Noise ratio S/N= 10 dB
Converting the above data into Noise Figure NF in dB we get:
-6 2
( Vin x 10 ) x 20
NF = 10 log [ ------------------------ ] + 174
dB 10 BW x S/N
Where:
Vin = input signal = 0.11 uV (microvolt)
BW = Band Width for SSB = 2400 Hz
S/N = Signal to Noise ratio = 10 dB i.e. 10 time in power ratio
-6 2
( 0.11 x 10 ) x 20
NF = 10 log [ --------------------------- ] + 174 = 4 dB
dB 10 2400 x 10
Showing a NF= 4 dB the IC 821 H seems to be a very good sensitive receiver
but if you want to improve the overall Noise Figure using an antenna mounted
preamplifier the Noise Figure of it must be less than 1 dB and infact the
Noise Figure of a AR SP432VDG is NF= 0.55 dB and the only change between
two models is only the gain because model VDG has a gain of 24 dB while the
model VDA has a gain of 15 dB
The important thing here adding an antenna mounted preamplifier to a
receiver is not to overload the receiver with a very high noise coming from
the preamplifier gain.
Addind RF stages in cascade the rule of thumb is the following one:
"When adding a preamplifier if the noise increases by 10 dB than the overall
noise of the receiving system is not deteriorated "
Since the NF of a AR SP432VDA is 0.55 dB and the gain is 15 dB if the coax
cable between the output of your preamplifier and receiver input is not too
long and lossy then you will not overload the IC 821 H because the S meter
reading with the preamplifier ON will be only about two S units of more
noise but the overall Noise Figure of your receiver system will be in the
range between 0.55 dB and 1 dB so that you will get a consistent improvement
in sensitivity.
About the above matter also please read the following letters :
http://www.db0anf.de/app/bbs/messages/show-AMSATBB4673
73" de
i8CVS Domenico
----- Original Message -----
From: "Paul Delaney - K6HR" <paul.hamradio@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Sent: Wednesday, March 09, 2011 7:11 PM
Subject: [amsat-bb] IC-821H Frontend Overload?
> I'm setting up for satellite operation and considering the AR2 SP432VDG
24db preamp. A friend suggests this will likely overload the frontend of the
radio (an 821H) The antennas are M2 eggbeaters. Would the SP432VDA 15db be a
better choice?
>
> Can anyone using these preamps give me some feedback on the 15db vs. 24db
preamps and which might be the best way to go considering the radio and
antennas I have?
>
> Paul Delaney
> paul.hamradio@xxxxxxx.xxx
> http://k6hr.dyndns.org:8080
> _______________________________________________
> 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: 15
Date: Thu, 10 Mar 2011 18:11:23 +0000 (UTC)
From: Bob- W7LRD <w7lrd@xxxxxxx.xxx>
Subject: [amsat-bb] Fwd: [PNWVHFS] FS: Yaesu FT-736R with 222 and 1296
modules
To: amsat-bb@xxxxx.xxx
Message-ID:
<362161066.2269188.1299780683278.JavaMail.root@xxxxxxx.xxxxxxxxxx.xx.xxxx.xxxx
xxx.xxx>
Content-Type: text/plain; charset=utf-8
I am just fowarding as it has some satellite capabilities.
73 Bob W7LRD
----- Forwarded Message -----
From: "Clay W7CE" <w7ce@xxxxxxx.xxx>
To: pnwvhfs@xxxxxxxxxxxx.xxx
Sent: Thursday, March 10, 2011 9:49:15 AM
Subject: [PNWVHFS] FS: Yaesu FT-736R with 222 and 1296 modules
I've decided to sell my FT-736R. ?This hasn't been an easy decision
because I really like this radio. ?However, I now have 2M, 222 and 432
on my Flex-5000A and can use my TS-2000X on 1296 until I get a
transverter working with the 5000A. ?So it's time to let someone else
enjoy this radio.
It is in excellent condition and, in addition to the hard to find 222
and 1296 modules, has the optional CW Keyer, 600Hz narrow-band CW filter
and FTS-8 CTCSS Tone Encoder/Decoder. ?I have the manual, AC & DC power
cords and I'm pretty sure that I still have the original box (I'll have
to look for that when I get home tonight). ?Everything on the radio
works as it should and anyone who has worked me on 222, 432, or 1296 has
heard this radio.
Price is $1700 firm. ?If you try to buy the 222 and 1296 modules to add
to a stock radio you can expect to spend about $1000-1100. ?I could make
more money by parting it out, but I'm not going to do that. ?I'm not in
a hurry to sell it, so I'm giving 1st priority to hams in the Pacific
Northwest (we need more of us on 222 and 1296). ?I can bring it to
Puyallup this weekend or make arrangements to meet in WA or OR for
pickup. ?If someone local doesn't show an interest in the next month or
two, then I'll consider shipping it out of the area.
73,
Clay ?W7CE
360-951-0817 (cell)
--
~The Voice of the Pacific NorthWest VHF Society~
You received this message because you are subscribed to the Google Groups
"PNWVHFS" group.
To post to this group, send email to PNWVHFS@xxxxxxxxxxxx.xxx
To unsubscribe from this group, send email to
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------------------------------
Message: 16
Date: Fri, 11 Mar 2011 04:15:07 +1000
From: Andrew Rich <vk4tec@xxxxxxxxxxxxx.xxx>
Subject: [amsat-bb] Re: IC-821H Frontend Overload?
To: i8cvs <domenico.i8cvs@xxx.xx>
Cc: Amsat - BBs <amsat-bb@xxxxx.xxx>
Message-ID: <776E35BC-8F7B-43FD-9F8B-8931A8E8002D@xxxxxxxxxxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
Very good explanation
Sent from my iPhone
Andrew Rich
On 11/03/2011, at 4:01, "i8cvs" <domenico.i8cvs@xxx.xx> wrote:
> Hi Paul, K6HR
>
> The SSB and CW sensitivity of an IC 821H in 70 cm is less than 0.11uV
> for a Signal to Noise ratio S/N= 10 dB
>
> Converting the above data into Noise Figure NF in dB we get:
> -6 2
> ( Vin x 10 ) x 20
> NF = 10 log [ ------------------------ ] + 174
> dB 10 BW x S/N
>
> Where:
>
> Vin = input signal = 0.11 uV (microvolt)
> BW = Band Width for SSB = 2400 Hz
> S/N = Signal to Noise ratio = 10 dB i.e. 10 time in power ratio
>
> -6 2
> ( 0.11 x 10 ) x 20
> NF = 10 log [ --------------------------- ] + 174 = 4 dB
> dB 10 2400 x 10
>
> Showing a NF= 4 dB the IC 821 H seems to be a very good sensitive receiver
> but if you want to improve the overall Noise Figure using an antenna mounted
> preamplifier the Noise Figure of it must be less than 1 dB and infact the
> Noise Figure of a AR SP432VDG is NF= 0.55 dB and the only change between
> two models is only the gain because model VDG has a gain of 24 dB while the
> model VDA has a gain of 15 dB
>
> The important thing here adding an antenna mounted preamplifier to a
> receiver is not to overload the receiver with a very high noise coming from
> the preamplifier gain.
>
> Addind RF stages in cascade the rule of thumb is the following one:
>
> "When adding a preamplifier if the noise increases by 10 dB than the overall
> noise of the receiving system is not deteriorated "
>
> Since the NF of a AR SP432VDA is 0.55 dB and the gain is 15 dB if the coax
> cable between the output of your preamplifier and receiver input is not too
> long and lossy then you will not overload the IC 821 H because the S meter
> reading with the preamplifier ON will be only about two S units of more
> noise but the overall Noise Figure of your receiver system will be in the
> range between 0.55 dB and 1 dB so that you will get a consistent improvement
> in sensitivity.
>
> About the above matter also please read the following letters :
>
> http://www.db0anf.de/app/bbs/messages/show-AMSATBB4673
>
> 73" de
>
> i8CVS Domenico
>
> ----- Original Message -----
> From: "Paul Delaney - K6HR" <paul.hamradio@xxxxxxx.xxx>
> To: <amsat-bb@xxxxx.xxx>
> Sent: Wednesday, March 09, 2011 7:11 PM
> Subject: [amsat-bb] IC-821H Frontend Overload?
>
>
>> I'm setting up for satellite operation and considering the AR2 SP432VDG
> 24db preamp. A friend suggests this will likely overload the frontend of the
> radio (an 821H) The antennas are M2 eggbeaters. Would the SP432VDA 15db be a
> better choice?
>>
>> Can anyone using these preamps give me some feedback on the 15db vs. 24db
> preamps and which might be the best way to go considering the radio and
> antennas I have?
>>
>> Paul Delaney
>> paul.hamradio@xxxxxxx.xxx
>> http://k6hr.dyndns.org:8080
>> _______________________________________________
>> 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
>
> _______________________________________________
> 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
------------------------------
_______________________________________________
Sent via amsat-bb@xxxxx.xxx. Opinions expressed are those of the author.
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End of AMSAT-BB Digest, Vol 6, Issue 148
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