Of noisy power supplies and logs

An interesting week on the bands. Some days have been plagued by poor propagation, whilst others have shown what the shortwave bands can offer up when conditions are good. The 13th gave an excellent illustration of the importance of MUF (Maximum Usable Frequency) to international broadcasters. This is the maximum frequency which can support good communications to the target area. During the late afternoon/evening of the 13th, I started monitoring on the higher bands (16m and 19m). These proved to be somewhat poor in offerings, so I moved down to the 25m band. Well, what a difference! S.E. Asia, Africa and Australia, came bounding in. ABC Australia on 12065 was the strongest I had ever heard it! I’m guessing that with the prevailing conditions, the MUF was probably around 13 Mhz.

I use a laptop for logging and checking station ID’s (using SWSKEDS lists). This is a somewhat ancient (in modern terms) Lenovo Z60m. I bought it s/hand about 3 years ago, when it was already about 5 y.o.. It came with an after market power supply/charger, the original probably having been lost or broken. This power supply, being a poorly constructed switch mode type, has always caused huge amounts of noise across all bands. Even adding a filter on the mains side made no difference. It also became very hot during use, which became apparent when I checked the specs. The original charger supplies 20v at up to 4.5 A. The after market one was rated at 20v and 3.25 A! No wonder it was getting hot. During any listening activity, I had to unplug the charger, which only gave me about 45 minutes listening time at a spell.

So I have now purchased the correct one and what a difference. Completely noise free across all bands, and it doesn’t get hot. So now my listening sessions can span a much longer period! It has been the best £20 I’ve spent in a long time. Sometimes it pays to get better equipment!

And so to the logs. All received, as usual, using a Yeasu FT-450D, a homebrew half size OCFD, via a homebrew ATU.

5025 Khz Cuba R Rebelde 06:23 UTC Spanish. LA Music and chat SINPO: 33333 2016-02-16

17830 Khz Ascension Island BBCWS 16:10 UTC English. West Ham v Norwich City SINPO: 54444 2016-02-13

13640 Khz India AIR 18:55 UTC Music. SINPO: 54455 2016-02-13

11635 Khz North Korea V.O. Korea 19:36 UTC English. Military music. SINPO: 33333 2016-02-13

11660 Khz Ascension Island BBCWS 19:38 UTC Hausa. Music and chat. SINPO: 33333 2016-02-13

11735 Khz Zanzibar ZBC 19:41 UTC Swahili. Music and chat. Some deep QSB SINPO: 32233 2016-02-13

11750 Khz South Africa AWR 19:47 UTC Igbo. Religious broadcast. SINPO: 44444 2016-02-13

11810 Khz Ascension Island BBCWS 19:51 UTC English. Magazine article about renewable technology in Costa Rica. SINPO: 43333 2016-02-13

11900 Khz Sao Tome VOA 19:54 UTC French. Female announcer with discussion program. SINPO: 43333 2016-02-13

12050 Khz Oman R Sultanate of Oman 19:58 UTC Arabic. Music and chat SINPO: 33333 2016-02-13

12065 Khz Australia R Australia 19:59 UTC English. ID at 20:00 followed by News. SINPO: 54444 2016-02-13

9390 Khz Thailand R Thailand 19:04 UTC English. ‘The Morning News Hour’ SINPO: 44444 2016-02-17

9420 Khz Greece V.O. Greece 19:38 UTC Greek. Discussion program. SINPO: 54444 2016-02-17

9470 Khz Botswana VOA 19:40 UTC Kinyarwanda. Discussion program SINPO: 43344 2016-02-17

15340 Khz Australia Reach Beyond Australia 15:15 UTC English. Religious discussion. SINPO: 32233 2016-02-19

15505 Khz Bangladesh Bangladesh Betar 15:18 UTC Hindi. Female announcer SINPO: 32222 2016-02-19

15545 Khz Vatican City R Tamazuj 15:22 UTC Sudanese. Music and chat. SINPO: 32233 2016-02-19

11650 Khz Phillipines FEBC Manilla 15:51 UTC Russian. Discussion program. SINPO: 54444 2016-02-19

11695 Khz Phillipines Vatican Radio 15:53 UTC Classical music. Tinang relay SINPO: 44444 2016-02-19

11870 Khz Phillipines VOA 16:02 UTC Burmese. Phone-in discussion. SINPO: 33333 2016-02-19

11995 Khz Thailand BBCWS 16:09 UTC Farsi. Discussion program. Unbelievably strong signal. Arm-chair copy. SINPO: 54455 2016-02-19

12045 Khz Thailand BBCWS 16:12 UTC Dari. Discussion program.
SINPO: 54444 2016-02-19

9390 Khz Thailand R Thailand 19:24 UTC English. ‘Radio Thailand News’ SINPO: 44444 2016-02-19

9505 Khz Sudan V O Africa 19:29 UTC Hausa. Closing music and sign off SINPO: 22222 2016-02-19

9525 Khz Indonesia V O Indonesia 19:33 UTC English. ID and contact details at 19:34. Somewhat muffled modulation. Discussion about the problems of plastic bags. SINPO: 43344 2016-02-19

9625 Khz Japan R Japan 20:08 UTC Japanese. Male announcer SINPO: 22222 2016-02-20

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s