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CX2SA > SATDIG 05.10.13 21:03l 896 Lines 30316 Bytes #999 (0) @ WW
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Sent: 131005/1902Z @:CX2SA.SAL.URY.SA #:11861 [Salto] FBB7.00e $:AMSATBB8341
From: CX2SA@CX2SA.SAL.URY.SA
To : SATDIG@WW
Today's Topics:
1. Digital QRM on FO-29 (Paul Stoetzer)
2. Re: 2m--> 10.7Mhz downconverter (John Stephensen)
3. Stacking LEO and Terrestial antennas (Dean Maluski)
4. Re: Crushcraft A144-10T "VHF Twist" Antenna (i8cvs)
5. Re: AMSAT-BB NF formula posting (i8cvs)
6. Re: 2m--> 10.7Mhz downconverter (i8cvs)
7. Re: AMSAT-BB NF formula posting (Nick Pugh K5QXJ)
8. [Re: AMSAT-BB NF formula posting (amended) (i8cvs)
9. Re: Digital QRM on FO-29 (DF opportunity!) (Robert Bruninga)
10. Re: Digital QRM on FO-29 (DF opportunity!) (Stefan Wagener)
11. Re: Digital QRM on FO-29 (DF opportunity!) (Paul Stoetzer)
----------------------------------------------------------------------
Message: 1
Date: Fri, 04 Oct 2013 16:51:43 -0400
From: Paul Stoetzer <n8hm@xxxx.xxx>
To: AMSAT-BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Digital QRM on FO-29
Message-ID: <524F2A5F.8050409@xxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
During two passes of FO-29 - at around 0120Z last night and around 1430Z
this morning, I've heard some QRM that sounds like a digital signal. I
confirmed that others heard it too and it wasn't local QRM, so it's
obviously being relayed by the satellite. Downlink is around 435.860 MHz
(I heard it around 435.865 last night as the satellite was approaching
and around 435.855 MHz this morning as the satellite was moving away),
so the signal is likely being transmitted around 145.940 MHz.
Has anybody else heard it? Any ideas on what the source might be?
73,
Paul Stoetzer, N8HM
Washington, DC
------------------------------
Message: 2
Date: Fri, 4 Oct 2013 21:08:09 -0000
From: "John Stephensen" <kd6ozh@xxxxxxx.xxx>
To: "Andy Brian" <briaandy@xxxxx.xxx>, "AMSAT-BB" <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: 2m--> 10.7Mhz downconverter
Message-ID: <05B7941524B14030A949D2C347A97B00@xxxxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
For a demonstration, the easiest route would be to modify a 2-meter
receiving downconverter from Down East Microwave or another supplier. Change
the crystal oscillator frequency and retune the IF output to 10.7 MHz. If
you have a choice of IF frequencies use 21.4 MHz as this would be closer to
the usual 28 MHz output.
73,
John
KD6OZH
----- Original Message -----
From: "Andy Brian" <briaandy@xxxxx.xxx>
To: "AMSAT-BB" <amsat-bb@xxxxx.xxx>
Sent: Friday, October 04, 2013 04:45 UTC
Subject: [amsat-bb] 2m--> 10.7Mhz downconverter
> Hi,
>
>
> I need help to find any good design for the 2m to 10.7MHz downconverter
> which I'll try to use for presentation linear transverter.
> Please if you have any or point me to any good books where to find?
>
> Thanks for all answers,
>
>
> BR Andy
> _______________________________________________
> 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: 3
Date: Fri, 04 Oct 2013 08:31:08 -0400
From: Dean Maluski <dean@xxxxx.xxx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Stacking LEO and Terrestial antennas
Message-ID: <1380889868.4906.8.camel@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset="UTF-8"
I have a pair of antennas, 440 and 2 meter LEO typical setup with G-5500
rotor and fiberglass horizontal boom.
It is mounted about 18 inches above top of tower on vertical mast.
I can probably push it up another 1.5 feet before having to add on to
vertical mast.
I would like to also hang a Cushcraft A3S a couple inches above top of
tower on mast.
I think the back of 2 meter antenna is about 5~6 feet that rotates
downward when chasing LEO's.
The reflector on A3S dimension is 7 feet horizontally from mast.
I'm wondering if anyone has a setup similar to this and if there are is
a negative impact of antenna proximity?
I haven't bought the A3S yet. Want to be fairly comfortable this will
work OK before I make the investment in the A3S HF Yagi.
------------------------------
Message: 4
Date: Sat, 5 Oct 2013 05:13:46 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
To: "Amsat - BBs" <amsat-bb@xxxxx.xxx>, <les@xxxxxxxxxxxx.xxx>
Subject: [amsat-bb] Re: Crushcraft A144-10T "VHF Twist" Antenna
Message-ID: <001001cec178$e8d40b50$0301a8c0@xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Les, N1LF
To built a polarization switching for a crossed yagi Cushcraft
A144-10 T is unpractical because the antenna and the phasing
harness are using PL connectors and the coax relays are normally
supplied with N type connectors.
You can't remove the PL connectors from the phasing harness
because they are crimped over two 1/4 electrical length of
RG-59/U and one 1/4 electrical lenght of RG-58/U so that
cutting and removing the original PL connectors those 1/4
wavelengt lines will became shorter than 90 degrees.
BTW you can rebuild a new phasing line using six N connectors
for the phasing line, two N female N barrels connectors,a N type
T connector and change the PL with N flanged female connectors
over the gamma match arms of both dipoles.
The cost for all N connectors and coax relay will be higher than
the cost of a new modern crossed yagi available with switching
polarization relay as new in the USA market.
Since your antenna will be mounted inside your large attic and it
will stay high and dry, I suggest you to connect your A144-10 T
as originally designed connecting the phasing harness for RHCP
or LHCP and stay happy with the compromise results obtined.
73" de
i8CVS Domenico
----- Original Message -----
From: "Les Rayburn" <les@xxxxxxxxxxxx.xxx>
To: "i8cvs" <domenico.i8cvs@xxx.xx>
Sent: Friday, October 04, 2013 5:57 AM
Subject: Re: [amsat-bb] Crushcraft A144-10T "VHF Twist" Antenna
> Domenico,
>
> Thank you for your wise advice. Unfortunately a new cross-polarized
> antenna is not in the cards right now due to budget.
>
> Would it be possible and practical to build a polarization switching
> relay for the antenna to allow me to rapidly switch between RHCP and LHCP?
>
> The connectors are not an issue, since it will be mounted inside my
> large attic. It will stay high and dry.
>
> 73,
>
> Les N1LF
>
>
>
>
>
>
> On 10/3/2013 10:39 PM, i8cvs wrote:
> > ----- Original Message -----
> > From: "Les Rayburn" <les@xxxxxxxxxxxx.xxx>
> > To: "AMSAT Mailing List" <amsat-bb@xxxxx.xxx>; <starcom-bb@xxxxxxxx.xxx>
> > Sent: Friday, October 04, 2013 4:18 AM
> > Subject: [amsat-bb] Crushcraft A144-10T "VHF Twist" Antenna
> >
> >
> >> I just acquired a "new" in the-box, never assembled Crushcraft A144-10T
> >> "VHF Twist" antenna. It includes the cabling to allow the user to
select
> >> left or right hand polarization. My questions are numerous:
> >>
> >> 1.) How is the performance on this antenna, compared to more modern
> >> designs?
> > Hi Les,N1LF from Domenico, i8CVS
> >
> > 1) I have used the A144-10T since 1973 and compared to modern
> > type it works no so well because the phasing harness to switch
> > polarizations uses crimped PL connectors and you get water and
> > humidity into it.
> >> 2.) If I were going to install it inside my attic, should I chose left
> >> or right hand polarization?
> > 2) To switch between RHCP and LHCP you must screw and unscrew
> > by hand the phasing harness connectors and since the antenna is not
> > equipped with a polarization switching relay you have not the time
> > to switch polarization while operating the satellite.
> >> 3.) Any caveats or things to watch out for?
> >>
> > 3) Do not use the above Cushcraft A144-20 T for the above reason.
> > Buy a modern model of crossed yagi with polarization switching
> > relay between RHCP to LHCP possibly from 2M
> >
> >> Any information that could be provided would be great. I was thrilled
> >> when a friend stopped by and asked me if I'd be interested in the
> >> antenna. Good price too.
> >>
> >>
> > I understand a good price because it is a old model of antenna
> > wich designe is almost back 30 yars ago. BTW the aluminum is
> > a good quality and witstand on the environment for many years.
> >
> >> --
> >> 73,
> >>
> >> Les Rayburn, N1LF
> >> 121 Mayfair Park
> >> Maylene, AL 35114
> >> EM63nf
> >>
> >> 6M VUCC #1712
> >> AMSAT #38965
> >> Grid Bandits #222
> >> Southeastern VHF Society
> >> Central States VHF Society Life Member
> >> Six Club #2484
> >>
> >> Active on 6 Meters thru 1296, 10GHz & Light
> > 73" de i8CVS Domenico
> >
> >
>
------------------------------
Message: 5
Date: Sat, 5 Oct 2013 05:24:06 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
To: "AMSAT-BB" <amsat-bb@xxxxx.xxx>, "Ralph Wallio, W0RPK"
<W0RPK@xxxxxx.xxx>
Subject: [amsat-bb] Re: AMSAT-BB NF formula posting
Message-ID: <002401cec17a$59d8e2c0$0301a8c0@xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Ralph, W0RPK
I will write the formula in another arithmetical form:
NF = ( Vi x 10^-6 )^2 ) x 20 ) / (BW x S/N ) ) log ) x 10 ) + 174
dB 10
where:
Vi = input signal in uV applied over the 50 ohm RX input
BW = Band Wide in Hz (2400 Hz for SSB)
S/N = Signal to Noise ratio in power ratio = 10
Going to your YAESU FT-726 R the sensitivity is specified for 10 dB of
(S+N)/N and not for 10 dB of S/N so that we must convert first (S+N)/N into
S/N with the following formula:
S + N
S/N = ----------- - 1 = 10 log (10-1) = 9.54 in power ratio
N 10
Calculating the sensitivity for 2 meters SSB/CW less than 0.15 uV for 10
dB (S+N)/N we have:
NF = ( 0.15 x 10^-6)^2 ) x 20 ) / ( 2400 x 9.54 ) ) log ) x 10 ) + 174
= 6.9 dB
dB
10
____________________________________
Calculating the sensitivity for 70 cm SSB/CW less than 0.15 uV for 12 dB
(S+N)/N we have:
S + N
S/N = ----------- - 1 = 10 log (15.84 -1) = 14.84 in power ratio
N 10
NF = (0.15 x 10^-6 )^2 ) x 20 ) / ( 2400 x 14.84 ) ) log ) x 10 ) + 174
= 5.01 dB
dB
10
CONCLUSION:
The sensitivity in 2 meters and 70 cm is the same 0.15 uV but in 70 cm 0.15
uV are specified for 12 dB (S+N)/N and not 10 dB (S+N)/N as in 2 meters and
so it happen that the receiver is more sensitive in 70 cm
The formulas where published into an old issue of the Ham Radio Magazine
early about 1973 and I have to find it in my many papers after that I will
send a copy to you but I remember it very often ant this numbars are burned
into my brain HI HI !
I hope this helps and if you have any question please let me know.
73" de i8CVS Domenico
----- Original Message -----
From: Ralph Wallio, W0RPK
To: domenico.i8cvs@xxx.xx
Sent: Friday, October 04, 2013 4:48 PM
Subject: AMSAT-BB NF formula posting
Domenico --
Thanks for posting the NF formula. Your results for the ICOM IC-R10 cause
me to reconsider what I have been estimating
for my much older YAESU FT-726R. Specifications from the Yaesu Operating
Manual:
2m SSB/CW Less than 0.15uV for 10dB (S+N)/N
70cm SSB/CW Less than 0.15uV for 12dB (S+N)/N
I would like to make this calculation myself but I am having trouble
duplicating your results probably due to uncertainties
resulting from how the formula is formatted by AMSAT-BB.
Perhaps you have a document source to suggest that will resolve these
uncertainties.
TNX es 73 de Ralph W0RPK
------------------------------
Message: 6
Date: Sat, 5 Oct 2013 05:26:24 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
To: "Andy Brian" <briaandy@xxxxx.xxx>, "AMSAT-BB" <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: 2m--> 10.7Mhz downconverter
Message-ID: <003901cec17a$ac383a20$0301a8c0@xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "Andy Brian" <briaandy@xxxxx.xxx>
To: "AMSAT-BB" <amsat-bb@xxxxx.xxx>
Sent: Friday, October 04, 2013 6:45 AM
Subject: [amsat-bb] 2m--> 10.7Mhz downconverter
> Hi,
>
> I need help to find any good design for the 2m to 10.7MHz downconverter
> which I'll try to use for presentation linear transverter.
> Please if you have any or point me to any good books where to find?
>
> Thanks for all answers,
>
>
> BR Andy
Hi Andy,
I have never seen in the market a 2 meters downconverter with an IF
of 10.7 MHz
If your 10.7 MHz IF is a value strictly mandatory the only way for you
is to modify a 144 to 28 MHz downconverter in wich the local oscillator
is made with a original XTAL of 144-28 = 116 MHz
The new XTAL must be 144 - 10.7 = 133.3 MHz overtone wich is
difficult to find and must be ordered to a company that cut crystals.
Remember that who cut crystals must have precise specifications in
order to know if it must be series resonant and if it must be 3? or 5?
overtone and the best way is to send to the above company a photocopy
of the original downconverter schematic diagram.
Actually it is very difficult to find in Europe labs that cut only one
XTAL per frequency except the EISCH ELECTRONIC in 89079
Ulm Gogglingen wich cut and supply one XTAL in a week or two
at a price of about US $ 35,00. Here the internet address:
http://www.eisch-electronic.com/index.html
In addition you must retune the local oscillator coil and trimmers
to get the circuit to oscillate at 133.3 MHz
Also you must retune the IF output circuit after the mixer to get
the maximum output at 10.7 MHz IF.
Another choise easier for you should be to buy an old downconverter
144/28 MHz and convert the 28 MHz IF into a second IF of 10.7 MHz
using a single mixer and a local oscillator with a XTAL of
28 - 10.7 = 17.3 MHz...........VERY EASY !
have fun
73" de i8CVS Domenico
------------------------------
Message: 7
Date: Sat, 5 Oct 2013 03:08:52 -0500
From: "Nick Pugh K5QXJ" <quadpugh@xxxxxxxxx.xxx>
To: "'i8cvs'" <domenico.i8cvs@xxx.xx>, "'AMSAT-BB'"
<amsat-bb@xxxxx.xxx>, "'Ralph Wallio, W0RPK'" <W0RPK@xxxxxx.xxx>
Subject: [amsat-bb] Re: AMSAT-BB NF formula posting
Message-ID: <000301cec1a2$21c6ea30$6554be90$@xxx>
Content-Type: text/plain; charset="us-ascii"
Domenico nice explanation please send the papers to the list
Thanks
nick
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of i8cvs
Sent: Friday, October 04, 2013 10:24 PM
To: AMSAT-BB; Ralph Wallio, W0RPK
Subject: [amsat-bb] Re: AMSAT-BB NF formula posting
Hi Ralph, W0RPK
I will write the formula in another arithmetical form:
NF = ( Vi x 10^-6 )^2 ) x 20 ) / (BW x S/N ) ) log ) x 10 ) + 174
dB
10
where:
Vi = input signal in uV applied over the 50 ohm RX input BW = Band Wide in
Hz (2400 Hz for SSB) S/N = Signal to Noise ratio in power ratio = 10
Going to your YAESU FT-726 R the sensitivity is specified for 10 dB of
(S+N)/N and not for 10 dB of S/N so that we must convert first (S+N)/N into
S/N with the following formula:
S + N
S/N = ----------- - 1 = 10 log (10-1) = 9.54 in power ratio
N 10
Calculating the sensitivity for 2 meters SSB/CW less than 0.15 uV for 10
dB (S+N)/N we have:
NF = ( 0.15 x 10^-6)^2 ) x 20 ) / ( 2400 x 9.54 ) ) log ) x 10 ) + 174
= 6.9 dB
dB
10
____________________________________
Calculating the sensitivity for 70 cm SSB/CW less than 0.15 uV for 12 dB
(S+N)/N we have:
S + N
S/N = ----------- - 1 = 10 log (15.84 -1) = 14.84 in power ratio
N 10
NF = (0.15 x 10^-6 )^2 ) x 20 ) / ( 2400 x 14.84 ) ) log ) x 10 ) + 174
= 5.01 dB
dB
10
CONCLUSION:
The sensitivity in 2 meters and 70 cm is the same 0.15 uV but in 70 cm 0.15
uV are specified for 12 dB (S+N)/N and not 10 dB (S+N)/N as in 2 meters and
so it happen that the receiver is more sensitive in 70 cm
The formulas where published into an old issue of the Ham Radio Magazine
early about 1973 and I have to find it in my many papers after that I will
send a copy to you but I remember it very often ant this numbars are burned
into my brain HI HI !
I hope this helps and if you have any question please let me know.
73" de i8CVS Domenico
----- Original Message -----
From: Ralph Wallio, W0RPK
To: domenico.i8cvs@xxx.xx
Sent: Friday, October 04, 2013 4:48 PM
Subject: AMSAT-BB NF formula posting
Domenico --
Thanks for posting the NF formula. Your results for the ICOM IC-R10 cause
me to reconsider what I have been estimating
for my much older YAESU FT-726R. Specifications from the Yaesu Operating
Manual:
2m SSB/CW Less than 0.15uV for 10dB (S+N)/N
70cm SSB/CW Less than 0.15uV for 12dB (S+N)/N
I would like to make this calculation myself but I am having trouble
duplicating your results probably due to uncertainties
resulting from how the formula is formatted by AMSAT-BB.
Perhaps you have a document source to suggest that will resolve these
uncertainties.
TNX es 73 de Ralph W0RPK
_______________________________________________
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: 8
Date: Sat, 5 Oct 2013 14:12:09 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
To: "AMSAT-BB" <amsat-bb@xxxxx.xxx>, "Ralph Wallio, W0RPK"
<W0RPK@xxxxxx.xxx>, "Nick Pugh K5QXJ" <quadpugh@xxxxxxxxx.xxx>
Subject: [amsat-bb] [Re: AMSAT-BB NF formula posting (amended)
Message-ID: <000d01cec1c4$1f50c1a0$0301a8c0@xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Ralph, W0RPK and All on the list.
Unfortunately in my previous message i have taped few mistake but hopefully
the following calculation are actually correct.
I have rewrite the formula in another arithmetical form wich is easier to be
used and not is corrupted or differently formatted sending it through BB
NF = ( Vi x 10^-6 )^2 ) x 20 ) / (BW x S/N ) ) log ) x 10 ) + 174
dB
10
where:
Vi = input signal in uV applied across the 50 ohm RX input
BW = Bandwidth in Hz (2400 Hz for SSB)
S/N = Signal to Noise ratio in power ratio
The sensitivity for YAESU FT-726R of W0RPK in 2 meters is specified
for 10 dB of (S+N)/N and not for 10 dB of S/N as required by the formula
so that we must convert first (S+N)/N into S/N as follow.
S + N
S/N = ----------- - 1 = (10-1) = 9 in power ratio
N
Calculation of NF for sensitivity of 2 meters SSB/CW less than 0.15 uV for
10 dB (S+N)/N ........... we compute:
NF = ( 0.15 x 10^-6)^2 ) x 20 ) / ( 2400 x 9 ) ) log ) x 10 ) + 174 =
7.18 dB
dB
10
____________________________________-
The sensitivity for YAESU FT-726 R of W0RPK in 70 cm is specified
for 12 dB of (S+N)/N and not for 10 dB of S/N as required by the formula
so that we must convert first (S+N)/N into S/N as follow:
S/N = ( S + N ) / N ) - 1 = 10^( 12/10) ) -1 = 15.84 - 1 = 14.84 in power
ratio
Calculation of NF for sensitivity of 70 cm SSB/CW less than 0.15 uV for a
12 dB (S+N)/N ratio.............. we compute:
NF = (0.15 x 10^-6 )^2 ) x 20 ) / ( 2400 x 14.84 ) ) log ) x 10 ) +174
= 5.01 dB
dB
10
CONCLUSION:
2 meters: Noise Figure NF = 7.18 dB
70 cm: Noise Figure NF = 5.01 dB
The sensitivity voltage in 2 meters and 70 cm has the same value of
0.15 uV but in 70 cm 0.15 uV are specified for a 12 dB (S+N)/N ratio
and not for a ratio of 10 dB (S+N)/N as in 2 meters and so it happens
that the receiver is more sensitive in 70 cm
Please note that the above formula is valid only for Vi = input signal in uV
applied across the 50 ohm RX input.
Unfortunately the manufacturers do not specify if Vi of the sensitivity
specifications is the voltage that we read with the RF Signal Generator
connected to the receiver input or if Vi is the voltage that we read over
the Signal Generator with open output.
This can generate ambiguity in calculating NF because measurement
are made with a Signal Generator with 50 ohm impedance output
connected to the receiver input wich impedance is as well 50 ohm
so that the output voltage of the Signal Generator is divided in two
equal parts across both the internal 50 ohm impedances.
BTW many commercial receiver NF calculations are demonstrating
that the value of NF match very well with the input voltage Vi so that
we can assume that the manufacturers specifications are giving Vi
as the voltage applied across the 50 ohm receiver input.
The formulas where published into an old issue of the Ham Radio Magazine
early about 1973 and I have to find it in my many papers after that I will
send a copy to any one is interested to it.
I use this formula very often and this numbars are burned into my brain HI
HI !
Please Ralph let me know if your calculations match with the actual one ?!
I hope this helps and if there is any question please let me know.
73" de i8CVS Domenico
----- Original Message -----
From: Ralph Wallio, W0RPK
To: domenico.i8cvs@xxx.xx
Sent: Friday, October 04, 2013 4:48 PM
Subject: AMSAT-BB NF formula posting
Domenico --
Thanks for posting the NF formula. Your results for the ICOM IC-R10 cause
me to reconsider what I have been estimating for my much older YAESU FT-726R.
Specifications from the Yaesu Operating Manual:
2m SSB/CW Less than 0.15uV for 10dB (S+N)/N
70cm SSB/CW Less than 0.15uV for 12dB (S+N)/N
I would like to make this calculation myself but I am having trouble
duplicating
your results probably due to uncertainties resulting from how the formula is
formatted by AMSAT-BB.
Perhaps you have a document source to suggest that will resolve these
uncertainties.
TNX es 73 de Ralph W0RPK
------------------------------
Message: 9
Date: Sat, 5 Oct 2013 09:25:44 -0400
From: Robert Bruninga <bruninga@xxxx.xxx>
To: Paul Stoetzer <n8hm@xxxx.xxx>
Cc: AMSAT-BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Digital QRM on FO-29 (DF opportunity!)
Message-ID:
<CALdCfN+Yyhfma1+byQx0ZjGJk6OTC3vMnSL6Q6+vjx-gLwEPmg@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Wow, a GREAT DF opportunity and exercise. The Doppler info is there
to determine its location. Just plot the doppler and note the center
point and draw a line of bearing through it. Combine with others and
find the source.
heh heh... though, complicated by having to subtract out your own...
But we should develop these techniques. They are the basis of all of
the original Search And Rescue satellite systems.
In fact!!! Why not get a few hams in a few areas of the country to
operate a CW carrier (at low power) at a known frequency in 4 corners
of the US and let evreyone practice their techniques. This way, we
learn how to do it on a known signal.
Just a thought.
Bob, WB4APR
On Fri, Oct 4, 2013 at 4:51 PM, Paul Stoetzer <n8hm@xxxx.xxx> wrote:
> During two passes of FO-29 - at around 0120Z last night and around 1430Z
> this morning, I've heard some QRM that sounds like a digital signal. I
> confirmed that others heard it too and it wasn't local QRM, so it's
> obviously being relayed by the satellite. Downlink is around 435.860 MHz (I
> heard it around 435.865 last night as the satellite was approaching and
> around 435.855 MHz this morning as the satellite was moving away), so the
> signal is likely being transmitted around 145.940 MHz.
>
> Has anybody else heard it? Any ideas on what the source might be?
>
> 73,
>
> Paul Stoetzer, N8HM
> Washington, DC
> _______________________________________________
> 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: 10
Date: Sat, 5 Oct 2013 09:09:25 -0500
From: Stefan Wagener <wageners@xxxxx.xxx>
To: Robert Bruninga <bruninga@xxxx.xxx>
Cc: AMSAT-BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Digital QRM on FO-29 (DF opportunity!)
Message-ID:
<CAKu8kHB68jY8YnUQRP2rkxaHyjq-CHBWNCVfHeLOM_9OiG79dg@xxxx.xxxxx.xxx>
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At one point, folks were using PSK31 on FO-29.
Check the waterfall and see how it looks like :-)
Stefan, VE4NSA
On Sat, Oct 5, 2013 at 8:25 AM, Robert Bruninga <bruninga@xxxx.xxx> wrote:
> Wow, a GREAT DF opportunity and exercise. The Doppler info is there
> to determine its location. Just plot the doppler and note the center
> point and draw a line of bearing through it. Combine with others and
> find the source.
>
> heh heh... though, complicated by having to subtract out your own...
> But we should develop these techniques. They are the basis of all of
> the original Search And Rescue satellite systems.
>
> In fact!!! Why not get a few hams in a few areas of the country to
> operate a CW carrier (at low power) at a known frequency in 4 corners
> of the US and let evreyone practice their techniques. This way, we
> learn how to do it on a known signal.
>
> Just a thought.
>
> Bob, WB4APR
>
> On Fri, Oct 4, 2013 at 4:51 PM, Paul Stoetzer <n8hm@xxxx.xxx> wrote:
> > During two passes of FO-29 - at around 0120Z last night and around 1430Z
> > this morning, I've heard some QRM that sounds like a digital signal. I
> > confirmed that others heard it too and it wasn't local QRM, so it's
> > obviously being relayed by the satellite. Downlink is around 435.860 MHz
> (I
> > heard it around 435.865 last night as the satellite was approaching and
> > around 435.855 MHz this morning as the satellite was moving away), so the
> > signal is likely being transmitted around 145.940 MHz.
> >
> > Has anybody else heard it? Any ideas on what the source might be?
> >
> > 73,
> >
> > Paul Stoetzer, N8HM
> > Washington, DC
> > _______________________________________________
> > 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!
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>
------------------------------
Message: 11
Date: Sat, 05 Oct 2013 10:14:10 -0400
From: Paul Stoetzer <n8hm@xxxx.xxx>
To: Stefan Wagener <wageners@xxxxx.xxx>
Cc: AMSAT-BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Digital QRM on FO-29 (DF opportunity!)
Message-ID: <52501EB2.8020107@xxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
It definitely wasn't PSK31. I'll post the audio of it when I get a
chance tomorrow.
73,
Paul, N8HM
On 10/5/2013 10:09 AM, Stefan Wagener wrote:
> At one point, folks were using PSK31 on FO-29.
>
> Check the waterfall and see how it looks like :-)
>
> Stefan, VE4NSA
>
>
> On Sat, Oct 5, 2013 at 8:25 AM, Robert Bruninga <bruninga@xxxx.xxx
> <mailto:bruninga@xxxx.xxx>> wrote:
>
> Wow, a GREAT DF opportunity and exercise. The Doppler info is there
> to determine its location. Just plot the doppler and note the center
> point and draw a line of bearing through it. Combine with others and
> find the source.
>
> heh heh... though, complicated by having to subtract out your own...
> But we should develop these techniques. They are the basis of all of
> the original Search And Rescue satellite systems.
>
> In fact!!! Why not get a few hams in a few areas of the country to
> operate a CW carrier (at low power) at a known frequency in 4 corners
> of the US and let evreyone practice their techniques. This way, we
> learn how to do it on a known signal.
>
> Just a thought.
>
> Bob, WB4APR
>
> On Fri, Oct 4, 2013 at 4:51 PM, Paul Stoetzer <n8hm@xxxx.xxx
> <mailto:n8hm@xxxx.xxx>> wrote:
> > During two passes of FO-29 - at around 0120Z last night and
> around 1430Z
> > this morning, I've heard some QRM that sounds like a digital
> signal. I
> > confirmed that others heard it too and it wasn't local QRM, so it's
> > obviously being relayed by the satellite. Downlink is around
> 435.860 MHz (I
> > heard it around 435.865 last night as the satellite was
> approaching and
> > around 435.855 MHz this morning as the satellite was moving
> away), so the
> > signal is likely being transmitted around 145.940 MHz.
> >
> > Has anybody else heard it? Any ideas on what the source might be?
> >
> > 73,
> >
> > Paul Stoetzer, N8HM
> > Washington, DC
> > _______________________________________________
> > Sent via AMSAT-BB@xxxxx.xxx <mailto: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 <mailto: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 member? Join now to support the amateur satellite program!
http://amsat.org/mailman/listinfo/amsat-bb
End of AMSAT-BB Digest, Vol 8, Issue 341
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