Category: SARTS Talks

Talks and presentations

Ham Radio via Satellites

Hardware, Software, Experiences

SARTS talk by Klaus, 9V1KG, 29th July 2021

Klaus presented his setup and experiences working linear Satellites.

Satellites-9V1KG presentation (pdf)Download

Satellite Audio Samples

Hope 1 CW telemetry
TO-108 – some strange tones before the CW transmission starts
Athenoxat-1 – Singapore Satellite from Giulio, 9V1FC
Calling CQ on RS-44 – right channel: CW side tone, left channel: signal from the satellite. Clearly to hear the Doppler shift.
RZ0CQ calling in CW via RS-44
Tunig in my SSB signal
CQ SSB – right channel: Up link, left channel: Downlink
JA3IKC answering my call
Nayif-1 telemetry signal 1K2 BPSK

Satellite Operation Outdoor Planning SOOP

https://github.com/9V1KG/soop

FCC Amateur Radio Licensing Guide for Singapore HAMs

by 9V1DT, April 2021

A short guide by Sampath how to prepare for and get the FCC license. The US FCC license is well recognized world wide and sometimes can be helpful to get a visitor’s ham radio license abroad.

FCC-Amateur-licensing_v3_20210402Download

One page guide as pdf (9V1YP):

Guide-to-get-FCC-ham-radio-licenceDownload

Applying the Concept of Earth-Moon-Earth (EME)

by Philip Lai, 9V1PL

This article was motivated by my fellow HAMs from the satellite group. Based on my success with the application of the concept of EME on 2 m to our SARTS Repeater without line of sight, I hope this write up can help those in the hobby with similar challenges to explore the concept of EME.

Earth-Moon-Earth communication (EME), also known as moon bounce, is a radio communications technique, which relies on the propagation of radio waves from an earth-based transmitter directed via reflection from the surface of the moon back to an earth-based receiver.

The challenge of my location (QTH)

I am located at the South Eastern Coast of Singapore, an apartment dweller with low elevation of 25 m facing south west. The distance to the Singapore VHF repeater is approximately 12 km. The small balcony with an opening of just slightly over 100 degrees is surrounded by tall buildings and makes it difficult for me to reach the repeater located at Dover.

For many months, when I first started as a new HAM, all I could hear was noise from my handheld (HT).

Each time I pushed the PTT, I couldn’t trigger the repeater, but even when I could trigger the repeater, I couldn’t hold it transmitting. It was frustrating, I fully understand, if you are facing similar challenges.

Continue reading Applying the Concept of Earth-Moon-Earth (EME)

Experiences with SDRs and active antennas

9V1KG, Klaus, Feb 2021

The presentation gives an overview on SDRs under $ 200 and active antennas for the HF range, and how to setup a simple and low budget SWL and monitoring station.

SDR-PresentationDownload

Audio samples

Received on 160 m with active loop and RTL SDR with up-converter.

E2X on 160 m during ARRL 160 m Contest
7C1B on 160 m during the same contest

Comparison between signals received on 80 m (YB2BFF) with ICOM 7300 and 5 m whip antenna with loading coil, and RTL-SDR with up-converter, active loop antenna and GQRX software receiver.

ICOM 7300 with 5 m whip antenna on 80 m
RTL-SDR with active loop antenna on 80 m

PSK Reporter

PSK reporter link to see current stations received.