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TRANSMITTING FM, AM, SSB, SSTV AND FSQ WITH JUST A RASPBERRY PI

Previously we posted about the Raspberry Pi’s ability to modulate one of its pins to produce FM transmissions with PiFM. A developer (F5OEO) has recently expanded on this idea, and now the Raspberry Pi is capable of modulating and transmitting FM, AM, SSB, SSTV and FSQ signals anywhere between 130 kHz to 750 MHz.

[…]

Building an APRS iGate using a Raspberry Pi and a TV tuner dongle

I’ve been messing around with APRS – the Automatic Packet Reporting System – for some time now and had noticed an absence of coverage in my local area. The end goal of APRS is to feed packets (which might be position data, weather reports, messages or other information) to the APRS-IS (which can be […]

KISS TNC by m0pzt

Projects : KISS TNC Most of this project is based-upon the firmware from Mobilinkd but some discrete parts and some soldering (or breadboard) is required to get things working. By re-flashing an Arduino-compatible microcontroller, it’s possible to turn it into a KISS TNC for use with APRS/AX25. Depending upon where you get your ‘duino […]

Arduino Multiband Beacon

Arduino Multiband Beacon INTRO http://blog.dxers.info/2016/01/been-playing-around-with-39usd-arduino.html 144 MHz (2 meters) http://blog.dxers.info/2016/01/arduino-uno-si5351a-breakout-as-144.html 432 MHz (70cm) http://blog.dxers.info/2016/01/arduino-uno-si5351a-breakout-as-432mhz.html 902 MHz http://blog.dxers.info/2016/02/arduino-uno-si5351a-breakout-as-902mhz.html TESTS http://blog.dxers.info/2016/02/etherkit-si5351a-beacon-and-another.html MULTI-BAND Operation (successful) http://blog.dxers.info/2016/02/arduino-tinkerkit-etherkit-si5351a.html 5-BAND Operation (TESTING) http://blog.dxers.info/2016/02/arduino-tinkerkit-etherkit-si5351a_9.html

 

ที่มา: http://blog.dxers.info/p/arduino-multiband-beacon.html

[…]

VHF BEACON AND APRS TRACKER

VHF BEACON AND APRS TRACKER (ENGLISH VERSION) 29/06/2015f4goh

This little low cost FM transmitting card can be used for different applications, like:

APRS Tracker APRS WX station APRS for sounding balloon Fox hunt Beacon for emergency exercice

Most of the time , the transmission of an APRS signal is AFSK , that is […]

Broadband Multi-Wire ANTENNA BARRETT

BROADBAND MULTI-WIRE ANTENNA BARRETT BC91200

This antenna consists of three wires connected at the both ends. In the middle of the central wire there is 50W 1250 Ohm resistor. External wires are cut in the middle, attached to isolators and feed through the balun.

Balun is wired on a ring shape ferrite core […]

HF Broadband Antenna

Broadband Antennas:

Diagram above: Broadband VertaLoop as described in this article. Wire loop supported by trees, Diamond BB7V Vertical Element with feedpoint resistive matching unit, “ground” radial wire, metal support pole, coaxial cable, ferrite feedline choke clamps, and grounding points.

Concepts and Construction of the Broadband VertaLoop Antenna Design and Installation Notes by […]

แปลง Raspberry PI ให้เป็น เครื่องส่งวิทยุ

Learn how to build a FM Radio Transmitter using a Raspberry Pi. This little hack doesn’t need anything much other than the Raspberry Pi and a Jumper cable. It allows you to transmit any audio content through the Raspberry Pi. Building this Raspberry Pi Radio Transmitter wouldn’t take more than 15-20 minutes to set up […]

Raspberry Pi ส่งภาพจากกล้อง ด้วย SSTV

ติดตั้งกล้อง

 

การ Capture รูปจากกล้อง (โปรแกรม raspistill ติดตั้งมาแล้ว)

raspistill -t 1 –width 320 –height 256 -e png -o /tmp/image.png

 

การเพื่ม Callsign ลงในรูป

mogrify -pointsize 24 -draw “text 10,40 ‘E27AF’” /tmp/image.png

ต้องติดตั้ง mogrify ด้วยคำสั่ง

$ sudo apt-get install imagemagick

 

เตรียมการส่ง

./pisstv /tmp/image.png 22050

จะได้ไฟล์ .wav สำหรับส่งออกด้วยเสียง

 

ต้องติดตั้งโปรแกรม pisstv เพื่อทำการแปลงรูปให้เป็นสัญญาณเสียงในรูปแบบของ sstv ก่อน

download ได้จาก […]

ทำสายอากาศ รวบรวมข้อมูล 14/1/59

http://www.oknation.net/blog/E22CTX/2009/03/13/entry-3 http://www.108ham.com/?id=198 http://www.feed-auto.com/bbu/antenna.htm http://www.100watts.com/smf/index.php?topic=82771.0 http://www.e27ae.com/index.php?topic=1577.0 http://www.feed-auto.com/bbu/antenna.htm http://www.utenwater.com/forums/index.php?topic=348. http://www.gpsteawthai.com/index.php?topic=2589.0 http://www.hamsiam.com/smf/index.php?topic=97720.0 http://www.hs8jyx.com/html/vhf_uhf_matching.html http://hs8jyx.blogspot.com/2015/05/yagi-2e-24-mhz.html

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