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Project Notes

#388 Singapore Radio Band Activity

Notes on official band plans for Singapore and my and personal observations on where the activity is found.

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Notes

Singapore is relatively progressive when it comes to radio spectrum allocation and use - for example, AM services disappeared by 2000 or so, DAB came and went in 2011 (rendered irrelevant by Internet services and continued popularity of FM). With the almost universal adoption of mobile and internet technology, the general perception is that shortwave and amateur radio are pretty much a thing of the past. Singapore has an amateur radio association (SARTS) - which I am not a member of (yet).

So as I become more interested in RF, my first question is basic: so is there much activity, and if so, what modes and bands?

This document is going to be a work-in-progress. It comprises my notes on:

  • frequency allocations and services
  • personal observations i.e. signals I’ve actually been able to receive
  • mainly shortwave and amateur bands

IMDA Spectrum Allocation

The IMDA maintains allocations for amateur radio that are roughly in line with ITU Region 3 guidelines. Excluded are bands at the low and high end: 2200m, 630m, 23cm.

imda_sg_spectrum

Shortwave Broadcast Services

The following is a personal log of shortwave broadcast services I have been able to receive in central Singapore.

Service Frequency (kHz) Meter Band Language Transmitter Scheduled Time (GMT) Received
BBC World Service 3915 75m   Singapore 22:00 - 00:00  
BBC World Service 6195 49m   Singapore 10:00 - 13:00, 22:00 - 00:00  
BBC World Service 7300 41m   Oman 22:00 - 23:00  
BBC World Service 9740 31m   Singapore 10:00 - 13:00  
Reach Beyond Australia 11865 25m   Kununurra 11:30 - 12:45 2018-01-31 Wed 20:57 UTC+8
China Radio International 11910 25m   Beijing 500 kw 13:00 - 13:57 2018-01-31 Wed 21:55 UTC+8
China Radio International 11710 25m Chinese Nanning 954 100 kw 07:00 - 08:00 2019-03-23 Wed 15:08 UTC+8
China Radio International 11875 25m Chinese Nanning 954 100 kw 07:00 - 08:00 2019-03-23 Wed 15:08 UTC+8
China Radio International 13660 22m English Xian 594 500 kw 07:00 - 07:57 2019-03-23 Wed 15:15 UTC+8
China Radio International 15145 22m Chaozhou Xian 594 500 kw 07:00 - 07:57 2019-03-23 Wed 15:16 UTC+8
NHK World Radio Japan 15280 19m Japanese Ibaragi-Koga-Yamata 300kw 06:55 - 08:58 2019-03-23 Wed 15:19 UTC+8
China National Radio 1 15480 19m Chinese Beijing 572 100kw 06:00 - 09:00 2019-03-23 Wed 15:21 UTC+8
China National Radio 1 17595 16m Chinese Shijiazhuang 723 100kw 06:00 - 09:00 2019-03-23 Wed 15:29 UTC+8
China National Radio 2 15500 19m Chinese Beijing 491 150kw 06:00 - 09:00 2019-03-23 Wed 15:22 UTC+8
China Radio International 17710 16m English Beijing 500 kw 06:00 - 08:00 2019-03-23 Wed 15:25 UTC+8
China Radio International 17740 16m Chinese Xian 594 500 kw 06:00 - 08:00 2019-03-23 Wed 15:23 UTC+8
China Radio International 17750 16m Chaozhou Xian 594 500 kw 07:00 - 07:57 2019-03-23 Wed 15:23 UTC+8
China Radio International 17650 16m Chinese Kashi-Saibagh 2022 500 kw 06:00 - 09:00 2019-03-23 Wed 15:26 UTC+8
China Radio International 17670 16m English Kashi-Saibagh 2022 500 kw 07:00 - 09:00 2019-03-23 Wed 15:28 UTC+8
Radio Saudi 17895 16m Arabic Riyadh 500 kw 02:55 - 08:00 2019-03-23 Wed 15:34 UTC+8
             

9V Amateur Radio Band Plans

  • NB: Narrow band modes including Digital modes not exceeding 2 kHz
  • WB: Wide band modes including FM
band frequency range
70cm 430 MHz UHF
2m 144 MHz VHF
10m 28 MHz HF
12m 24 MHz HF
15m 21 MHz HF
17m 18 MHz HF
20m 14 MHz HF
30m 10 MHz HF
40m 7 MHz HF
80m 3.5 MHz HF
160m 1.8 MHz MF

160m, 1.8 MHz

  • nighttime only band; during daylight, signals absorbed by the D-layer and the band is dead
  • after local sunrise, propagation to 1000 to 2300 miles is possible
  • signals peak at about local midnight
  • during summartime, conditions are limited due to atmospheric noise and storms
  • efficient antennas are essential
  • can be challenging because of the large sizes required for efficient antennas

9v_160m

80m, 3.5 MHz

  • nighttime only band but can provide some daytime action
  • distances limited to about 250 miles during the day
  • for DX, efficient antennas are essential

9v_80m

40m, 7 MHz

  • most popular QRP band
  • tends to follow ionization levels closely
  • day: distances to 500 miles
  • night:
    • signals rise quickly after dusk
    • recombination of F-layer means unsettled conditions 10-11pm local
    • once F settles, transcontinental possible
    • simple dipole suspended 25-40 feet
    • even mediocre antennas perform well

9v_40m

30m, 10MHz

  • great for QRP
  • open day and night
  • summer noise levels lower than 40m but absorbtion greater than 20m

9v_30m

20m, 14 MHz

  • lowest frequency DX band, considered among the best for DX
  • open most time to various areas of the world
  • closely follows ionization levels in upper ionosphere

9v_20m

17m, 18 MHz

  • mainly daylight band
  • must be sufficient solar activity to produce band openings
  • can produce outstanding DX to most areas of the world

9v_17m

15m, 21 MHz

  • mainly daylight band
  • must be sufficient solar activity to produce band openings
  • propagate primarily via reflection off of the F2 layer
  • can produce outstanding DX to most areas of the world

9v_15m

12m, 24 MHz

  • daylight band
  • can produce outstanding DX during much of the solar cycle
  • band forms up several hours after sunrise
  • normal skip distance about 900 miles

9v_12m

10m, 28 MHz

  • portion of the shortwave radio spectrum, HF
  • daylight band
  • can produce outstanding DX during much of the solar cycle
  • at peak solar cycle, can achieve extremely long-distance signals, refracting from the F2 layer
  • band forms up several hours after sunrise
  • normal skip distance about 900 miles
  • summertime sporadic-E openings

9v_10m

2m, 144 MHz

  • portion of the VHF radio spectrum
  • predominately used for FM or digital voice communications through repeaters
  • mainly local (50 miles), but DX possible with tropospheric ducting, sporadic E and meteor scatter
  • SARTS maintains a 2m repeater, managed by 9V1AI.
    • Repeater Tx 145.625 MHz
    • Repeater Rx 145.025 MHz
    • CTCSS Tone 156.7 Hz

9v_2m

70cm, 430 MHz

  • portion of the UHF radio spectrum internationally allocated to amateur radio and amateur satellite use
  • predominately used for FM or digital voice communications through repeaters
  • overlaps with the LPD433 band used by short range devices/RC models

9v_70cm

Credits and References

About LEAP#388 Radio
Project Source on GitHub Project Gallery Return to the LEAP Catalog

This page is a web-friendly rendering of my project notes shared in the LEAP GitHub repository.

LEAP is my personal collection of electronics projects, usually involving an Arduino or other microprocessor in one way or another. Some are full-blown projects, while many are trivial breadboard experiments, intended to learn and explore something interesting (IMHO!).

The projects are usually inspired by things found wild on the net, or ideas from the sources such as:

Feel free to borrow liberally, and if you spot any issues do let me know. See the individual projects for credits where due. There are even now a few projects contributed by others - send your own over in a pull request if you would also like to add to this collection.