Thursday, December 26, 2013

New Satellite planed for Launch in January 2014 from ISS

LituanicaSAT-1 with amateur radio FM transponder to deploy from ISS.
( Launch at 1:32 pm EST on Wednesday, January 8 2014)
You should be able to here this satellite on the webSDR

This satellite will be the first Lithuanian satellite.
1) VGA camera.
2) GPS receiver.
3) UHF CW beacon 100mW.
4) 9k6 AX25 FSK telemetry TX 2 watts.
5) FM Mode V/U transponder 150mW Voice Repeater.

  • FM Transponder Uplink 145.950 MHz Downlink 435.180 MHz 
  • AX25 Uplink 145.850 MHz AX25 Downlink 437.550 MHz 
  • CW Beacon 437.275 MHz 

 Read more at  , and here

Sunday, November 10, 2013

KKS-1 Satellite CW "5 JQ1YYY" log 10 November 2013 at 12:33 GMT

KKS-1 Satellite CW "5 JQ1YYY" log 10 November 2013 at 12:33 GMT (.....|.---|--.-|.----|-.--|-.--|-.--)

Here is the video with the CW recording of KKS-1

TISAT-1 Satellite recording log 10 Oct 2013 09 04 GMT

TISAT-1 Satellite recording log 10 Oct 2013 09 04 GMT

more details is available here
and here

  • Downlink:  beacon frequency is 437.305MHz
  • Power: 400mW
  • Callsign: HB9DE.
    TIsat-1 periodically identifies itself by its codename TISAT radiated as Morse code (CW) at 19WPM, along with basic telemetry.

CW beacon recording CW Beacon "HI HI HI TISAT R" 
(The R at the end indicate the temperature)

Recording was done on webSDR on 10 October 2013 at 09:04 GMT

Thursday, November 7, 2013

AENEAS Satellite Log Thursday 7 November 2013

AENEAS Satellite Log Thursday 7 November 2013

webSDR Settings

Video of Satellite reseption

Here is a log of the AENEAS Satellite on Thursday 7 November 2013. (9:53 SAST) GMT + 2

Tuning on WebSDR frequency  to 437.589Mhz on

Using Soundmodem at 1200 board

AENEAS Telemetry data:

1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [21:54:30R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [21:54:50R]

more data received on 9 November 8:35 (GMT)

1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:23:58R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:24:18R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:25:58R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:26:38R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:27:59R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:28:19R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:28:39R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:29:19R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:29:39R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:29:59R]
1:Fm KE6YFA-1 To CQ Via TELEM <UI F/R Pid=F0 Len=78> [22:30:19R]

More details on the Satellite is available here

Friday, November 1, 2013

Upcoming Satellites with transponders to look out for. FUNcube-1, FUNcube-2 on UKube-1, Delfi-n3Xt, FOX-1, FOX-2 and KletsKous

Upcoming Satellites with transponders to look out for.

FUNcube-1, FUNcube-2 on UKube-1, Delfi-n3Xt, FOX-1, FOX-2 and KletsKous (21 Nov 2013)

FUNcube-1 (1U CubeSAT) (More info available here
and here


FUNcube-1 will launch from Yasny base located in Orenburg Region, Russia on a DNEPR.
Launch Date:expected to be late November  2013.(Also on this launch is tw

Day time mode (Education Mode) Telemetry mode.
  • Beacon frequency: 1k2 BPSK 145.915Mhz
  • Night time mode (Amateur Mode) Transponder mode.
  • Transponder Up link 435.080 - 435.060 Mhz
  • Transponder Down link 145.930 -145.950 Mhz
POD partners, ZAcube from South Africa and HiNCube from Norway
read more about it here

FUNcube-2 (3U CubeSAT) FUNcube-2 is a subsystem on the UKube-1 satellite.
More info available from

Funcube-2 on  UKube-1 satellite
Communications systems:
  • 1k2 or 9k6 BPSK Telemetry downlink 145.840 MHz
  • FUNcube-2 1k2 BPSK Telemetry downlink 145.915 MHz
  • FUNcube-2 Transponder SSB/CW uplink 435.080 – 435.060 MHz and downlink 145.930 -145.950 MHz
  • S Band downlink 2401.0 MHz
  • myPocketQub 437.425-437.525 MHz

Triton-1 (3U cubesat) Launch  (21NOV2013)
ISIS-BV (Innovative Solutions In Space BV)

  • Main Downlink 145.815MHz & Backup Downlink 145.860MHz.
  • 600-700 km sun-sync orbit.
  • AIS (ship location service) radio science experiment.
  • Two U/V FM to DSB (“AO-16 mode”) repeaters.
  • Will be activated after 3 months (possibly both at once) 

Delfi-n3Xt (3U Cubsat)
More info available from

Communications systems:
  • Downlink 145.870 MHz and 145.930 MHz
  • Downlink 2405.00 MHz high speed
  • Linear transponder Uplink 435.530 – 435.570 MHz Downlink145.880 – 145.920 MHz.

FOX-1 (Fox-1 Assigned for launch in November 2014 on the ELaNa XII mission)
More info available from

Communications systems:
  • FM analog transponder.
  • Telemetry sent simultaneously with voice in sub-audio band as low-speed FSK.
  • Data Mode FSK Digital data up to 9600 bps

More info from
Communications systems:
  • Linear transponder.

KletsKous (1U Cubesat)
More info available here and

Communications systems:

  • Linear transponder.  uplink 70cm  downlink 2 metre

Sunday, October 13, 2013

CUSat 1&2

CUSat 1&2 (SpaceX Falcon 9 rocket launch)

ref :
and  :

You should be able to receive this satellite on this webSDR
CUSat Tracking Info:Cusat 1

  • Beacon Downlink Frequency: 437.405 MHz FM (UHF band)
  • Beaconed Callsign: BOTTOM
  • FCC Callsign: WG2XTI
  • Data Rate: 1200 baud
  • Modulation: AFSK
  • Transmit Interval: Every 1 minute
  • RF Power Output: 2.2 W
  • Antenna Polarization: Linear

CUSat Tracking Info:Cusat 2

• CUSat-2   437.485 MHz
• Cross link 437.305 MHz

Tuesday, October 8, 2013

OOREOS Satellite Telemetry reception report.

O/OREOS Satellite Telemetry reception report.

The reception was done over webSDR from on Windows using Chrome and Soundmodem.

More details regarding the webSDR is available here

Details on the OOREOS Satellite is available here

Here is my audio recording and telemetry data decoded on webSDR on 08 October 2013 at 18:22GMT.
Beacon: 437.305 MHz 1k2 AFSK, FM
1k2 AFSK Beacon signal of OREOS

Settings on webSDR was as follows.
Frequency :437281.50 Mhz
Band width settings 15.28 kHz @ -6dB; 15.74 kHz @ -60dB.
Modulation: FM.


Sound modem application can be found here

Here is the setting of the sound modem configuration.

Telemetry Data decoded with Soundmodem application.

1:Fm KF6JBP To UNDEF Via TELEM <UI F/C Pid=F0 Len=64> [20:22:01R]    77899F0100001602DAFC0133000000CF090D5F094300204B46
1:Fm KF6JBP To UNDEF Via TELEM <UI F/C Pid=F0 Len=64> [20:22:06R]    7C899F0200000902C90200A301430E9A000D5F094300204B46
1:Fm KF6JBP To UNDEF Via TELEM <UI F/C Pid=F0 Len=64> [20:22:36R]    99899F000200FE011BF601A102000286010D5F094300204B46

Some more data from 28 November 2013
1:Fm KF6JBP To UNDEF Via TELEM <UI F/C Pid=F0 Len=64> [23:04:00R]    43EDE2010000FA00DA800117000000CF090D5F094300204B46
1:Fm KF6JBP To UNDEF Via TELEM <UI F/C Pid=F0 Len=64> [23:04:05R]    48EDE2020000F400920000A3017A089A000D5F094300204B46
1:Fm KF6JBP To UNDEF Via TELEM <UI F/C Pid=F0 Len=64> [23:04:10R]    4DEDE2030000E70000060032022E0054050D5F094300204B46
1:Fm KF6JBP To UNDEF Via TELEM <UI F/C Pid=F0 Len=64> [23:04:55R]    79EDE2000000F1001B9E019C02000286010D5F094300204B46

Telemetry can be decoded with the free software of Mike Rupprecht, DK3WN:
You will also need this ocx at this link.

Monday, September 9, 2013

How to setup Putty to do X forwarding for Linux Ubuntu and Raspberry Pi.

How to setup Putty to do X forwarding for Linux Ubuntu and Raspberry Pi. (Remote desktop your Linux)Remote control your Linux and Raspberry Pi

What is X windows forwarding on Linux?

X windows forwarding allows you to local display the applications that is running on a remote Linux server.
Install your favorite X windows server on your MS windows PC.
I will install my favorite Cygwin x windows server and will explained the steps here.

Start the x Windows server.

You Should see a X in the icon bar at the bottom of your desktop.

When done continue with the Putty installation steps here

Install Putty and then run it to get to First configuration screen below.

1) Enter the Host-name or IP of your Linux server in host Name text box.  E.G
2) Enter the Port if its not the default port 22

Putty Start-up Configuration screen

2) Click on the Connection >> SSH >> X11 Category in the tree view.

3) Save the configuration.

4) Open your new configuration.
Enter your username and password.

login as: user1's password:
Welcome to Ubuntu 12.04.3 LTS (GNU/Linux 3.5.0-23-generic i686)

 * Documentation:

245 packages can be updated.
122 updates are security updates.

*** System restart required ***
Last login: Mon Sep  9 15:32:31 2013 from$ 

5) Now see if X fording is setup on your Linux (by default it is enabled but not for the root user)
Run the command echo $DISPLAY

The value could be localhost:12.0 or 10.0

Do not su to any user otherwise your DISPLAY setting will not work.

"ls -l .Xauthority"  in the home directory to verify a file named .Xauthority exists. If so it should show permissions -rw-------

If you have to su to a different user you will have to copy the Xauthority file from your home directory to the home of the su user as well and check if the DISPLAY setting is also correct.

If you don't have a DISPLAY setting then run this command. export DISPLAY=<value from step above> 

6)Test it with  xterm or xclock

it could take some time for the xterm application window to pop up on your MS windows desktop.

and there you have it.

If you want your Raspberry Pi Full desktop and not just the app you start you could use the command on the Raspberry Pi startlxde

Thursday, September 5, 2013

ZACUBE-1 (South Africa CubeSat-1)

ZACUBE-1 (South Africa)November 21st at  07:11:29 UTC.

The amateur radio CubeSat designed and built by students at the Cape Peninsular University of Technology in Bellville.
The current launch info has lift off scheduled for November 21st at  07:11:29 UTC.
Live launch video
You should be able receive ZACUBE-1 satellite on this weSDR.

Satellite seems to be in 1k2 mode at the moment.
The keps that seems to be the best at the moment is 2013-066B (27Nov2013) from

TX power at the moment 0.5 wat.
more info at
Here is a video recording of the telemetry.

The objectives of the mission are:
1) Training of post-graduate students in Satellite Systems Engineering.
2) Earth observation using a visible band matrix imager payload and an S-Band payload data transmitter (2.4 to 2.45 GHz).
3) UHF Store & Forward system (70 cm amateur band).

  • Uplink is 145.860 MHz
  • Downlink 437.345 MHz. Both links have selectable transmission rates of 1.2 kbps or 9.6 kbps.
  • Visible band matrix imager 115200 bps L-Band to S-band data transponder. (2.4 to 2.45 GHz).
  • HF beacon 14.099 MHz Hermanus Magnetic Observatory’s Dual Auroral Radar Network antenna at SANAE base in Antarctica (The HF beacon payload on 14.099 MHz ).
To decode the telemetry of ZAcube-1 download the software from
Telemetry format

0C 16 - header
7A 61 63 75 62 65 30 31 2E - ASCII Text message00 00 19 6d 2C - Timestamp (ticks)0B 0e 2C - Battery bus voltage (volt)06 ad 2C - OBC temperature (°C)00 2E - Command counter

Telemetry decoder from
Here is some pictures from the ZACUBE-1 camera

And many more follow the link to there site
Read more about it here.

Saturday, August 24, 2013

Now added 70cm Satellite webSDR with Egg Beater antenna and low noise amplifier.

Now added 70cm Satellite webSDR with Egg Beater antenna and low noise amplifier.

here is the link to the 70cm websdr described below

1) Eggbeater antenna.
Home build more details here
a Video on how to build the Eggbeater antenna

2) Low noise Amplifier (SP432VDG)


High Performance Inline Rf Switched Amateur Preamplifiers

3) RTL dongle
more info here
Where to get a dongle

4) webSDR
more info here

Saturday, July 27, 2013

EchoLink on Ubuntu (Setting up Svxlink server and qtel)

EchoLink on Ubuntu. (12.04) (Setting up Svxlink server and qtel)

Svxling is a application that allows you to setup a Echolink link or a Echolink repeater on your server.
You will need to build a interface between your computer Serial port and Mic and line in and outputs of the available sound card on your server.
Here is a typical interface diagram. You can get this interface in kit form at or prebuild versions at

Computer to Radio interface.

Jingtong Radio interface.
Jingtong HT

I now use the Baofeng uv-5r and not the Jingtong due to the squelch not being stable.

Qtel is a Echo link client that allows you to connect to Echolink system as a client simulating a radio. Communication is done using VOIP from your client to Echolink system.

Here is the steps that you neet to take if you want to set-up Svxlink link or you could only install client Qtel see nr 4.

You will have to verify your call-sign on with proof of your Radio amateur license documents. (The verification process can take 24 ours, so do it upfront and you need to verify your call sign for -L link and -R repeater options)

Ones this is done you will have call-sign and password required for the configuration below.

I would suggest you get a APRS servers password as well but is not required to get your Svxserver going. ( you could add the APRS functionality later.)
1) First add the Svxlink repository ref. to Ubuntu 
sudo add-apt-repository ppa:felix.lechner/hamradio

2) Update all repository config files for Ubutu.
sudo apt-get update

3) Install the Svxlink from the new repository configerd above.
sudo apt-get install svxlink-server

4) Install the qtel client.
sudo apt-get install qtel

5) Configure the Svxling server confugeration
sudo vi /etc/svxlink/svxlink.conf

6) Change the following fields in the /etc/svxlink/svxlink.conf file


     CALLSIGN=EL-ZR0ABC # callsign for a link EL for link and ER for repeater.

     PTT_PORT=/dev/ttyS0 # this could be a USB serial port  /dev/ttyUSB0 ?? change this to your device

     FREQUENCY=430.050 # tx-frequency is 145.550 MHz (Radio Frequency)


     TX_POWER=3 # tx output is 3 watts


     ANTENNA_GAIN=5 # antenna gain is 5 dBd


     ANTENNA_HEIGHT=10m # 10 meters above the ground 
     OR ANTENNA_HEIGHT=90 # 90 feet

Save the file.

Now comes the difficult part where you need to define your audio device for TX and RX.

Run the Command sudo aplay -l  This command will display all the alsa devices that can play sound to ext Speak.

sudo aplay -l
**** List of PLAYBACK Hardware Devices ****
Home directory /home/anton not ours.
card 0: Intel [HDA Intel], device 0: ALC662 rev1 Analog [ALC662 rev1 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

sudo arecord -l

In my case I only have one device "card 0: Intel [HDA Intel]"

You could properly use the device name Intel.

And to get the input device available on your computer run the command sudo arecord -l

sudo arecord -l

**** List of CAPTURE Hardware Devices ****
Home directory /home/anton not ours.
card 0: Intel [HDA Intel], device 0: ALC662 rev1 Analog [ALC662 rev1 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: V10 [FUNcube Dongle V1.0], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

In my case there was two devices and I wanted to use the same alsa device and above so it will be the "Intel" device
Defining alsa device by going to your home directory 
now edit the asla config file .asoundrc in your home directory (create one if it dose not exists)

sudo vi .asoundrc    The Intel part in the file must be changed to have your computers interface card name from the above process.

#This configuration file is for alsa interface configuration.
# 1) Intel motherboard (1 stereo input and 1 stereo output)
#************************** pcm definition ************************************
pcm.Intel_card {# defining the card to be used
     type hw
     card Intel # this has to be done to force reboot to point to same card
#************************* control section ***********************************
ctl.Intel_card {#defining the control interface
     type hw
     card Intel # this has to the same as above

Save the file.

Now edit the line AUDIO_DEV=alsa:pcm.Intel_card in the sudo vi /etc/svxlink/svxlink.conf file with the name U defined in the .asoundrc file U edited above ( in section Rx1 and Tx1)

Save the file.

Now you need to configure the echo-link connectivity details.
sudo vi /etc/svxlink/svxlink.d/ModuleEchoLink.conf

change the following fields.

CALLSIGN=CALLSIGN-L # your callsign

PASSWORD=your_verified_password #verify you callsign at

SYSOPNAME=your name and info

LOCATION=[Svx] Fq, your location town ....

DESCRIPTION="You have connected to a SvxLink node,\n"
            "a voice services system for Linux with EchoLink\n"
            "Check out for more info\n"
            "QTH:     South of Johannesburg, South Africa\n"
            "QRG:     Simplex link on 145.550 MHz\n"
            "CTCSS:   My_CTCSS_fq_if_any RX only working on TX Hz\n"
            "Trx:     My_transceiver_type Jingtong JT-208\n"
            "Antenna: My_antenna_brand/type/model Mag mount 1/4 on house roof\n"

Save a file and you should be ready to start the server.

Before we start the server with start-up script lets check if there is any errors.

Run the command sudo svxlink

if all is ok you should see something like this.

SvxLink v0.13.0 (Apr 15 2012) Copyright (C) 2011 Tobias Blomberg / SM0SVX

SvxLink comes with ABSOLUTELY NO WARRANTY. This is free software, and you are
welcome to redistribute it in accordance with the terms and conditions in the
GNU GPL (General Public License) version 2 or later.

Using configuration file: /etc/svxlink/svxlink.conf
--- Using sample rate 48000Hz

Starting logic: SimplexLogic
Home directory /home/anton not ours.
Loading module "ModuleHelp" into logic "SimplexLogic"
        Module Help v0.7.0 starting...
Loading module "ModuleParrot" into logic "SimplexLogic"
        Module Parrot v0.7.0 starting...
Loading module "ModuleEchoLink" into logic "SimplexLogic"
        Module EchoLink v0.10.1 starting...
*** WARNING: The value of ModuleEchoLink/LOCATION is too long. Maximum length is 27 characters.
Loading module "ModuleTclVoiceMail" into logic "SimplexLogic"
        Module Tcl v0.3.0 starting...
Event handler script successfully loaded.
EchoLink directory status changed to ON
--- EchoLink directory server message: ---
To ensure security, each
callsign used with EchoLink
must be validated.  The
callsign you are using has
not yet been validated.

Several different validation
options are available.  To
begin, please go to and click on


1) if you get an error like this.

*** ERROR: The sample rate could not be set to 8000Hz for ALSA device "pcm.Intel_card". The closest rate returned by the driver was 44100Hz.
*** ERROR: Could not open audio device for receiver "Rx1"

Most build in sound-cards should be able to handle 96000 or 48000Hz
Change the sample rate by editing the config file

Try uncommenting the CARD_SAMPLE_RATE=48000 and change it to 8000 or 16000 or 48000 in the /etc/svxlink/svxlink.conf file (high value is better)

2) if you get an error like this.

open serial port: Input/output error
*** ERROR: Could not initialize TX "Tx1"
*** ERROR: Could not initialize Logic object "SimplexLogic". Skipping...
*** ERROR: No logics available. Bailing out...

This means the serial port defined above PTT_PORT=/dev/ttyS0 is wrong and you need to get the correct port. (If you are using USB serial port it could be something like /dev/ttyUSB0)

3) If you get an error like this.
*** WARNING: SvxLink can only handle WAV files with sample rate 8000: /usr/share/svxlink/sounds/en_US/EchoLink/name.wav

It seems that the Ubuntu install install 16 bit audio files by default.
You can check the files by running the command.
file  /usr/share/svxlink/sounds/en_US/Default/0.wav
This what you will get from the command conferming it is 16bit

/usr/share/svxlink/sounds/en_US/Default/0.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 16 bit, mono 16000 Hz
I had to replace the files with this link

backup the existing wave files
Remove / uninstall the 16 khz files
sudo dpkg -r  svxlink-sounds-en-us-heather-16khz

Download the install file
Run sudo wget

Run the command
sudo dpkg -i svxlink-sounds-en-us-heather-8khz_11.11-1~raring~ppa1_all.deb

There should be now errors. (if there is errors tel me how you got it fixed below)
Normally you could just edit the /etc/svxlink/svxlink.conf file and fix the error.

My start up scrips did not work with the default instillation procedure as above and I had to add additional info in the script /etc/init.d/svxlink-server as follows.

4) If you get an error like this when you start up svxlink-server: 39: [: -eq: unexpected operator
It also means your PTT_PORT=/dev/ttyS0 is not set correctly.

I had to add the following lines.

Edit the file
sudo vi /etc/init.d/svxlink-server
add the following
LOGFILE=/var/log/svxlink # just below the PATH line

and changed RUNASUSER=svxlink to RUNASUSER=root 

Now lets start the Svxlink server.
sudo /etc/init.d/svxlink-server start

Check that the process is running.
sudo ps -ef | grep svxlink

We still need to adjust the audio levels for tx and rx.
run the alsa mixer to adjust the audio levels

run  sudo alsamixer   In my case I gad to set the Capture volume for the Audio from radio.

The log file will indicate if the level is set to high.

alsamixer (F5, F6, space bar, m, up, down selection keys )

Tail the log file for possible configuration errors when u start the server.

sudo tail -f /var/log/svxlink

To stop the server 
sudo /etc/init.d/svxlink-server stop

How to start Qtel client

sudo qtel

Linux Qtel Client

Qtel CLient

Client on windows

Echolink Client

Android Client
Echolink Station list

Link connection screen
Connection view

If the APRS server details, username and password is configured correctly you should be able to see your station on the APRS map.
What is nice is the fact that your APRS station details get updated with connection details as stations connect to your Svxlink server.


Please give me feedback on any mistakes.
more info is avalible at

Monday, July 15, 2013

Why not put your own Satellite in space ?

 for as little as $19.00

  1. Transmitter power is 10mW DSSS transmitted through a dipole. The maximum solar panel power available on the standard device is 100mW. 
  2. Hardware Development Scouts can potentially have as much as 500mW solar power.
  3. The orientation of the device in orbit around the earth should be able to be determined most accurately by use of the magnetometer.
  4.  It might also be possible to work out orientation by using the single pixel sensor as a moon/earth/sun sensor.
  5. They will be doing there best to make the landing site the earth side of the moon.
  6. If you are, or would like to be, a radio amateur, they will show you how to communicate directly with your spacecraft in space when it is nearby using inexpensive UHF and S-band equipment. Communication at (cis-)lunar distances is more expensive (typically requiring 5-24m+ steerable dishes), but available to some clubs and enthusiasts.

More info is available at

Tuesday, June 4, 2013

Shell scripts to stop and Start your rtl_tcp Dongle (bash script) on Linux

Shell scripts to stop and Start your RTL Dongle (bash script)

Script to start rtl_tcp
1) Create a directory where you will store your scripts and where to save your process id.

mkdir sh   
cd sh  
mkdir pid

2) Use your favorite text editor (vi ...) and create a file ( with the following content
3) Change the pid file path to your directory as well as where the rtl_tcp excusable is.
4) Add port , ip if so required.
5) to find the path to rtl_tcp directory just use the command type rtl_tcp and you should get the path returned.

#This program will write pid file
# We start app and create the pidfile
#Supported gain values for rtl_tcp (14): -1.0 1.5 4.0 6.5 9.0 11.5 14.0 16.5 19.0 21.5 24.0 29.0 34.0 42.0
        sudo $PROGRAM -g 42.0 &
        echo $PID > "$pidfile"
        echo Program has started

Create a stop script wit your editor ( in the same directory U created start script with the following content

#This program will readthe pid file
# We kill app and remove the pidfile``
        pid2kill=`cat $pidfile`
        kill -9 $pid2kill
        rm $pidfile

To run or stop the scripts just run sudo ./  or sudo ./

Hope this helps.