|
Navigation
Contact Details
Peter Miles
Northam, Western Australia
QRZ Page: VK6YSF
Email
Social
Media
Buy me a coffee
|
If you found information on this site interesting, beneficial, or learned something new, please consider buying me a cup of coffee by clicking the coffee cup below.
It helps keep the website going and is greatly appreciated.
|
|
|
|
MASTHEAD COAX CABLE
POWER FEED UNIT
Masthead equipment coaxial cable 12v power
feed unit.
The masthead equipment coaxial cable 12v power
feed unit is to provide an approximately 12 volt supply for equipment
at the top of the mast via the connecting coax cable.
The circuit injects a DC voltage into station end
of the coax cable and allowing the RF to pass un-attenuated to the
receiver while blocking the DC to the receiver. The circuit also
blocks RF from passing into the DC supply system.
Fig
1 Masthead coax cable
power feed unit schematic.
|
ID
|
DESCRIPTION
|
QTY
|
|
C1
& 2
|
CAPACITOR,
CERAMIC - 470n, 50V
|
2
|
|
D1
|
LED
|
1
|
|
D2
|
DIODE,
SCHOTTKY, 1N5822, 3A 40V
|
1
|
|
FUSE
|
TO SUIT
LOAD. TYPICALLY 100mA ~ 500mA, 3AG, GLASS, FAST OPERATION
|
1
|
|
L1
|
INDUCTOR,
470uH
|
1
|
|
R1
& 2
|
RESISTOR
- CARBON 1k,
0.25W
|
2
|
|
S1
|
SWITCH
|
2
|
Fig
2 Component detail
list.
|
|
|
|
Photo 1
The masthead equipment coaxial cable 12v power
feed unit viewed from the front.
|
Photo 2 The masthead equipment coaxial cable 12v power
feed unit viewed from the rear.
|
The
effect on mast end voltage from the electrical load of the equipment
at the masthead end
of the coax has been calculated in the below graphs for coax cable
lengths from 5m to 30m at a variety of loads. Loads of up to 500mA for
reasonable lengths of RG58 coax will deliver a sufficient supply
voltage.
Fig
3 The
chart shows the voltage at the masthead end of lengths of RG58 coax
against various loads.
Fig
4 The
chart shows the voltage at the masthead end of lengths of RG213 coax
against various loads.
Details
of the compact active wide-band receiving
antenna powered by masthead power
feed unit. See: ACTIVE ANTENNA V1
TOP
OF PAGE
Page
last revised 12 March 2022
|
|
|
Space Weather
https://www.swpc.noaa.gov/
|
Sir Ernest Thomas Fisk
born 8 August 1886
Establishment of a Beam Wireless Service, providing the longest and fastest telegraphic communications in the world. The first such communication between Australia and England was in January 1927.
|
Notice Board
|
VK6YSF JS8Call and
Olivia 8/250 operations.
Current activity is generally
focused - though not restricted to - JS8Call operations on the 20,
30m, and 40m bands.
Olivia 8/250 is used occasionally on the 20m band.
Proposed
band and mode activity
is often communicated on HamSpots: https://hamspots.net/js8/
or my profile on
X: https://x.com/vk6ysf97230
.
Post
date: 29 July 2026
|
|
Local
Repeaters
Repeaters Page Updated
- Expanded and refreshed information on VHF and UHF repeaters across Western Australia's Central Coast, Perth, the Avon Valley, and the Peel region. New AllStar Link information has also been added, including linked repeater details and
gateway information across the State.
See: https://vk6ysf.com/local_repeaters.htm
Post
date: 27 July 2026
|
|
MARMOTSat
Amateur radio CubeSat
now successfully in orbit
Payload includes:
145.875 MHz – AX.25 packet digipeater
436.125 MHz – Telemetry & command (digital)
29.410 MHz – CW telemetry beacon, DVB-S2 experiments.
https://marmotsat.ca
https://www.propagationlab.ca/satellite/
Tracking: SatNOGS
DB - MARMOTSat
Post
date: 29 July 2026
|
|
Western Australian SSTV net
Popular
Western Australian SSTV net for both digital and anolog SSTV.
Generally
found at 7214.0kHz LSB every afternoon from 08:00 UTC (4:00pm WST)
For more
details: https://www.wasstv.net/wasstv.net/index.html
Post
date: 8 December 2025
|
|
VK6MJM LF (136kHz) and MF (474kHz) Beacon
VK6MJM is a LF/MF station
located in Manjimup, Western Australia.
Common Mode: FST4W 300 (Similar to
WSPR)
Note:
other modes and sub-modes may be used.
Station details were presented by
Peter Hall (VK6HP) at PerthTech 2024.Presentation PDF: Peter
Hall VK6HP at PerthTech
QRZ Page: VK6MJM
on QRZ.com
Post
date: 10 March 2025
|
|
|
|
|
