Showing posts with label UHF. Show all posts
Showing posts with label UHF. Show all posts

Monday, May 21, 2018

How to Create a Linear Transponder using a RTL Dongle and HackRF with Gnu Radio.

How to Create a Linear Transponder using a RTL Dongle and HackRF with Gnu Radio.

I wanted to test the concept of a linear Transponder and how difficult would it be to build it with conventional components.
Hardware Configuration
Hardware required to build the Transponder.
  1. SDR IQ demodulator with rtl dongle (RF In)
  2. SDR IQ DSP processing system. Gnu Radio (DSP processing)
  3. SDR IQ Modulator. HackRF (RF Out)
  4. Background management system. (OBC) for additional telemetry.
Software required for Transponder.
  1. SDR IQ demodulator. rtl dongle (RF In)
  2. SDR IQ DSP processing system. Gnu Radio (DSP processing)
  3. SDR IQ Modulator. HackRF (RF Out)
  4. Background management system. (OBC)

Video of working Transponder.



Gnu Radio.


Transponder Block Diagram

RTL SDR Block.

RTL-SDR Source

Low Pass Filter Block.

 
Low Pass Filter Block

AGC Block.

AGC Block

Power Squelch.

Power Squelch

Osmocom Sink. (HackRF)

Osmocom Sink (HackRF)

FFT. (Spectrum View of input)

FFT Spectrum View

REF: Power point Slides at AMSAT SA

Ref:Source code is available on Github Version 4

Saturday, August 27, 2016

SDR Comparison

SDR Comparison

Name TypeFrequency rangeBand withChannelHost InterfaceWindowsLinuxMacEstimated price
AirSpy
Pre-build
24-1750 MHz
20 MSPS MSps ADC sampling, up to 80 MSPS 
1
USB
Yes
Yes
Yes using ports
US$199
SDRstick UDPSDR-HF1
Pre-built
0.1–30 MHz
80 Msps
1
1G Ethernet via BeMicroCV-A9
Yes
Yes
Yes
US$169
Apache Labs ANAN-10E
Pre-built
10 kHz – 55 MHz
122.88 Msps (14 bit ADC)
2
Gigabit Ethernet
Yes
Yes
Yes
US$995
Apache Labs ANAN-10/100
Pre-built
10 kHz – 55 MHz
122.88 Msps (16 bit ADC)
4
Gigabit Ethernet
Yes
Yes
Yes
US$1,649-US$2,449
Apache Labs ANAN-100D/200D
Pre-built
10 kHz – 55 MHz
122.88 Msps (16 bit ADC)
7
Gigabit Ethernet
Yes
Yes
Yes
US$3,299-US$3,999
SunSDR2
Pre-built
10 kHz – 160 MHz
160 MSPS
3/4
10/100 Ethernet, WLAN (embedded)
Yes
Yes
 ?
US$1,960
bladeRF
Pre-built
300 MHz - 3.8 GHz
80 kSPS - 40 MSPS
RX/TX (12-bit ADC/DAC)
 ?
USB 3.0 SuperSpeed
Yes
Yes
Yes
US$420
FLEX-6700
Pre-built
0.01–73, 135-165 MHz
245.76 MSPS (transceiver)
8/8
Ethernet
Yes
Yes
Yes
US$7,499
FLEX-6700R
Pre-built
0.01–73, 135-165 MHz
245.76 MSPS (receiver)
8/8
Ethernet
Yes
Yes
Yes
US$6,399
FLEX-6500
Pre-built
0.01–73 MHz
245.76 MSPS (transceiver)
4/4
Ethernet
Yes
Yes
Yes
US$4,299
FLEX-6300
Pre-built
0.01–54 MHz
122.88 MSPS (transceiver)
2/2
Ethernet
Yes
Yes
Yes
US$2,499
FLEX-5000A
Pre-built
0.01–65 MHz
48, 96, 192 kHz (transceiver)
2/2
1394a Firewire
Yes
No
No
US$2,800
FLEX-3000
Pre-built
0.01–65 MHz
48, 96 kHz (transceiver)
1/1
1394a Firewire
Yes
No
No
US$1,700
FLEX-1500
Pre-built
0.01–54 MHz
48 kHz (transceiver)
1/1
USB
Yes
No
No
US$650
Perseus
Pre-built
10 kHz – 40 MHz (87.5–108 MHz using FM down-converter)
80 MSPS
 ?
USB
Yes
Yes
 ?
US$1,199
SDRplay: Radio Spectrum Processor
Pre-built
0.1–2,000 MHz
0.5-12 MS/s and up to 8 MHz bandwidth
0/1
USB
Yes
Yes
Yes
US$149
ISDB-T 2035/2037
Pre-built
50–960 MHz
0.5-12 MS/s and up to 8 MHz bandwidth
0/1
USB
Yes
Yes
Yes
US$25
Soft66AD / Soft66ADD / Soft66LC4 / Soft66RTL
Pre-built
0.5–70 MHz
External ADC required (I/Q output)
0/1
USB
Yes
Unofficially
 ?
US$20
FUNcube Dongle
Pre-built
64–1700 MHz
96 kHz
0/1
USB
Yes
Yes
Yes
US$160
FUNcube Dongle Pro+
Pre-built
0.15–240 MHz, 420-1900 MHz
192 kHz
0/1
USB
Yes
Yes
Yes
US$200
FiFi-SDR
Pre-built
200 kHz – 30 MHz
96 kHz (integrated soundcard)
0/1
USB
Yes
Yes
 ?
€120
SDR-IQ
PnP
0.1 kHz – 30 MHz
66.666 MHz
1/1 ?
USB
Yes
Yes
Yes
US$525
WinRadio WR-G31DCC
Pre-built
9 kHz – 50 MHz
100 MSPS
3/3
USB
Yes
No
No
US$950
USRP B200
Pre-built
70 MHz to 6 GHz
56 Msps
 ?
USB 3.0
Yes
Yes
Yes
US$675
USRP B210
Pre-built
70 MHz to 6 GHz
56 Msps
 ?
USB 3.0
Yes
Yes
Yes
US$1,100
USRP N200
Pre-built
DC to 6 GHz
25 Msps for 16-bit samples; 50 Msps for 8-bit samples
 ?
Gigabit Ethernet
Yes
Yes
Yes
US$1,515
USRP N210
Pre-built
DC to 6 GHz
25 Msps for 16-bit samples; 50 Msps for 8-bit samples
 ?
Gigabit Ethernet
Yes
Yes
Yes
US$1,717
USRP X300
Pre-built
DC to 6 GHz
200 Msps
 ?
Gigabit Ethernet, 10 Gigabit Ethernet, PCIe
Yes
Yes
Yes
US$3,900
USRP X310
Pre-built
DC to 6 GHz
200 Msps
 ?
Gigabit Ethernet, 10 Gigabit Ethernet, PCIe
Yes
Yes
Yes
US$4,800
Cross Country Wireless SDR receiver v. 3
Pre-built
472–479 kHz, 7.0–7.3 MHz/10.10–10.15 MHz, and 14.00–14.35 MHz
External ADC required (I/Q output)
1/1
Crystal controlled two channels
Yes
Yes
Yes
US$80
Realtek RTL2832U DVB-T tuner
Pre-built with custom driver
24–1766 MHz (R820T tuner) (sensitivity drops off considerably outside this range, but can go 0–2,200 MHz (E4000 tuner with direct sampling mod))
2.4 MHz (can go up to 3.2 MHz but drops samples)
 ?
USB
Yes
Yes
Yes
US$8 - US$10
SoftRock-40
Kit
7.5 MHz
48 kHz
1
USB
Yes
Yes
Yes
US$21
SoftRock RX Ensemble II
Kit
180 kHz – 3.0 MHz, and 1.8–30 MHz operation
External ADC required (I/Q output)
1
USB
Yes
Yes
Yes
US$67
ZS-1
Pre-built
300 kHz – 30 MHz
10 kHz, 20 kHz, 40 kHz, 100 kHz
3
USB 2.0
Yes
No
No
€1,399
HackRF One
Pre-built
1 MHz - 6 GHz
8 Msps - 20 Msps
1
USB 2.0
Yes
Yes
Yes
US$299
HiQSDR
prebuilt modules & kits, pcbs
30 kHz - 62 MHz
48 - 960 kHz
 ?
10/100 Ethernet
Yes
Yes
No
US$650
US$1,400
KiwiSDR
Pre-built
0.1 - 30Mhz
30Mhz
4
Beagle black
yes
yes
yes
 USD 99
LimeSDR
Pre-built (full Open Source / Hardware)
100 kHz to 3.8 GHz
61.44 Msps (12 bit ADC)
 ?
USB 3.0, PCIe
Yes
Yes
Yes
US$299(USB) US$799(PCIe)

Sunday, May 17, 2015

Setting up the Kydera DM-880 Portable DMR (mototurbo)

Setting up the Kydera DM-880 Portable DMR (mototurbo)


Here is the instructions to setup the Kydera DM-880 to connect to the Amateur radio repeater network in South Africa.
What do you get with the Kydera DM-880 (Programming cable is optional)

How to Program the DM-880
You can download the Programming software here.
Here is the video how to install the Programming software.


Unzip the downloaded file and run the 
Here is a video on how to program the Kydera DM-880



You will have to change the Serial port number to below 10 for the software to able to access you radio.Change the serial port number by going to the computer settings devices. Then select the Kydera serial universal serial bus controllers  Right click and select properties and then select the port tab and change the port number below 10. Then un plug the serial cable from radio and replug it in computer. The new port should now be active and you can select it in the programming application.

Here is the Configuration file with the South Africa DMR Repeaters and Analog repeaters pre-configured mentioned in the video above.
 
Programming software here 
 






Friday, February 28, 2014

Baofeng HT Radios

Baofeng HT Radios. (UV-5RA) 2m (136-174Mhz) and 70cm (400-480Mhz) with a additional FM broadcast band Rx only (65-108Mhz) (the Transmitting power is (1 Low/4W High).
This radio should be ideal for Satellite work but it is not full duplex ;-(

Baofeng UV-5RA
Transceiver is available from http://www.giga.co.za
I have heard a lot about the small Baofeng HT radios and I was wondering how well they work.
Firstly when I looked around on the internet I found a whole range of the Devices with minor differences between them.

Here is some comparison differences I could found.

Radio Model Dual band Memory Channels Frequency range(s) Battery Power Tx Power Battery
UV-5R Yes 128 136 to 174 MHz and 400 to 480 MHz 12 hours 4/1W 1800-mAh
UV-3R Yes 99 136 to 174 MHz and 400 to 480 MHz broadcast band 68 to 108 MHz(RX) 10 hours 3 W 1800-mAh
UV-5RA Yes 128 136 to 174 MHz and 400 to 480 MHz broadcast band 68 to 108 MHz(RX) 12 hours 4/1W 1800-mAh
BF-888S No 16 400 to 470 MHz 8 hours 4W 1500-mAh
UV-100 Yes 99 136 to 174 MHz and 400 to 470 MHz Broadcast band 65 to 108 Mhz(RX) 10 hours 2W 1200mAh
UV-B5 Yes 99 136 to 174 MHz and 400 to 470 MHz 12 hours 5/1W 1800-mAh
UV-5RC Yes 128 136 to 174 MHz and 400 to 480 MHz broadcast band 68 to 108 MHz(RX)  ?? 4/1W 1800-mAh

Well I was surprised with the UV-5RA that I got and was reasonably easy to configure and program.
I got the repeater split set-up in no time after watching a YouTube video.

Here is the Microphone and external speaker connection details.

Both the modules is available from Giga Technology http://www.giga.co.za

Programming cable assembly.

Programming cable assembly.



Programming your Baofeng radio (UV-5R?)

Frequency Mode vs. Channel Mode
These two modes have different functions and often confused. 

  • Frequency Mode - Used for a temporary frequency assignment, such as a test frequency or quick field programming. 
  • Channel Mode - Used for selecting preprogrammed channels. 

All programming MUST be initially done in the Frequency Mode using the Upper Display only. From there you have the option of assigning the entered data to a specific channel for later access in the Channel Mode if desired.

IMPORTANT: Programming done using the Lower display cannot be saved and will be lost.  


Programming a Repeater Channel with Standard Offsets (600kHz minus offset)
  
This example is for:  146.700 MHz
600kHz minus offset
into channel 99
CTCSS tone 123.0

1.    Set radio to VFO Mode   (Frequency Mode)
      a.)     UV5R series - Press VFO/MR button
      b.)     UV82 - Turn radio OFF, then Press/Hold MENU button during PowerON.

2.    Select   Display A    (this is a must)
      a.)     UV5R/GT3 - Press     [A/B]      and select the Upper Display.
      b.)     UV82 - Press [EXIT A/B] and select the Upper Display.

3.    Disable TDR (Dual Watch/Dual RX) which toggles between A and B.
          Press  [Menu]   7   [Menu]
          Select OFF
          Press  [Menu]   [Exit]

4.    Delete Prior Data from the channel to be programmed.
          Press  [Menu]   2 8   [Menu]
          Enter   9 9   (Memory Channel to clear)
          Press  [Menu]   [Exit]

5.    Enter the Repeater Offset.
         Press [Menu]   2 6   [Menu]
         Enter  0 0 6 0 0
         Press  [Menu]   [Exit]

6.   Enter the Transmit Frequency Shift.
        Press  [Menu]   2 5   [Menu]
        Enter  2  for Minus shift. ( or    to  - )
        Press  [Menu]   [Exit]  

7.   Set CTCSS or DCS codes for Transmit. 
         ( example = CTCSS TX tone 123.0 Hz )
            Press  [Menu]   1 3   [Menu]
            Enter  1 2 3 0   [Menu]   [Exit]

8.   Enter the repeater output frequency,  1 4 6 . 7 0 0 

9.   Store RX frequency
        Press  [Menu]   2 7   [Menu] 
        Enter   9 9   (Memory Channel)  ( 000 to 127 )    
            This is the channel that was cleared in step 4. 
        Press  [Menu]   [Exit] 

10.  Press the [ * Scan ] button.     
         This activates  Reverse Mode and displays the TX frequency.

11.   Press  [Menu]   2 7   [Menu] 
         Enter the same Memory Channel entered above. 
         Press  [Menu] 

12.   Press the  [* Scan] again to exit the Reverse Mode.

13.   Press  [Exit]

This will now appear it in the channel list when you switch to Channel Mode. (MR)
Boafeng UV-VF5 Circuit diagram

REF http://www.uv3r.com/images/Schematic-Baofeng-UV5R.pdf

Radio programing details
here is a link to the Chirp program http://chirp.danplanet.com

Which antenna is best?

 It's all personal preference, but a good rule of thumb is:
 The longer the radiator, the better the range, especially on transmit.
 Short stubby antennas use a coil to match TX to 50 ohm, not radiate.
 The closer to 1/4 wavelength in the air, the better the performance.

NOTE:
      A field test was performed between 31 popular antennas.
     The results can be found HERE.   

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 http://live.cput.ac.za/live.html
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 http://www.celestrak.com/NORAD/elements/tle-new.txt

TX power at the moment 0.5 wat.
more info at http://www.cput.ac.za/fsati
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 http://www.dk3wn.info/software.shtml
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 http://www.dk3wn.info/software.shtml
Here is some pictures from the ZACUBE-1 camera


And many more follow the link to there site
http://www.cput.ac.za/blogs/fsati/2014/01/22/south-africa-on-a-clear-day-as-seen-by-tshepisosat/
Read more about it here.