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Reception report and 1566kHz 3NE anomalies


Dan Merta
 

Yesterday I went for a walk on Sandringham beach to Red Bluff on Port Phillip Bay in Sth East Melbourne VIC at around 1.00pm 
Whilst walking I had the radio (Digitech AR-1780) tuned to 1566 3NE Located in Wangaratta VIC which was fading randomly in and out from 0db up to 20db in signal. Displaying all the traits of a skywave signal in the middle of the day. 
Tuning to 3RN on 756kHz in Wangaratta also, showed about 02 to 03db in signal with no fading. 
At Red Bluff I tried some other freq and heard a very faint carrier from 2QN Deniliquin on 1521kHz. About 01db
I'm unable to figure out why 1566kHz 3NE behaves in this way,  am wondering it it's due to location? The freq it's on? Transmitter power output? Or a combination of all of the above? 

Anybody who lives in the Melb metro area or in Sth East VIC could listen on 1566kHz and will most likely hear the same phenomenon. 

Radio used was a Digitech AR-1780.
Cheers. Dan. 


Todd
 

Hi Dan,

From where I live in Sydney, 1566 KHz 3NE is 320 miles (515 km). During the winter months around solar noon, 3NE is received via residual E layer skywave. This is due to temporal weakening of the D layer. Normally the D layer blocks incident MW signals from reaching the higher E layer, but during the winter months, especially during low solar activity, sections of the D layer weaken to the point that a degree of signal is not blocked. The term residual means weak and patchy reception. This is why high gain receiving systems are usually required in order to hear daytime skywave signal strengths that are lower than evening strengths. A loop antenna is preferred at my location.

The high end of the MW band is especially sensitive to daytime residual skip. For example, 1503 KHz Melbourne (5 kW) at 450 miles is received via daytime skywave, but less frequently and at lower average signal strength compared to 1566 KHz 3NE. The ionosphere angle of incidence needs to be sufficiently high in order for the signal to penetrate the D layer. A longer distance path corresponds to a lower angle of incidence. This effectively creates a great circle distance limit for daytime skywave.

756 KHz 3RN was received via pure groundwave into Port Phillip Bay in Sth East Melbourne VIC. The frequency (756 KHz) was too low for daytime skywave. However, 1566 KHz 3NE, even though originating from the same general area, was sufficiently high in frequency for daytime skywave.

Regards,

Todd

PS: For Melbourne general area listeners, MW daytime skip targets:

1314, 1431, 1575 Wollongong.
1350 2LF Young.
1368 2GN Goulburn.
1395 5AA Adelaide.
1404 2PK Parkes.
1440 1EA Canberra.
1467 3ML Mildura.
1494 2AY Albury.
1521 2QN Deniliquin.
1539 5TAB Adelaide.


Gary DeBock
 

Dan and Todd,

1566-3NE has always had an overachieving signal, and it was a downright pest for me during a visit to Aitutaki in the Cook Islands in April of 2018.

It ran the Australia Overnight program, wiping out any chance of tracking down 1566-AIR in Nagpur, India. It also made reception of the 100 watt Norfolk Island Station (1566-VL2NI) next to impossible. 693-3AW was another Australia Overnight pest, although the 1000 kW 693-Bangladesh was strong enough to be competitive on occasion.

Gary DeBock (in Puyallup, WA, USA) 


Dan Merta
 

Hi Gary and Todd. 

Thanks for the feedback. I find that 3NE does this into Melbourne all year round. But I'm finding the information about  residual E layer skywave most informative. I will try for the other stations you have suggested Todd, with the aid of a loop antenna. 1314kHz has a semi local station 3BT Ballarat at 5k. I will try for the others. 1467kHz 3ML (River 1467) comes into Melb very well at night. Much stronger than 3SH 1332kHz.
Gary it's a pity you had to listen to Australia Overnight I wouldn't wish that on anyone lol. Unfortunately the Aust stations have been a pain for MW dx since 1987 when they began to broadcast 24/7. So they will block many possible catches in that region.   
The Chinese high powered MW stations are easy catches at this time of year, mainly CRN 5 on 837kHz, and CRN 6 on 684kHz and 909kHz. I can hear these even in high RF interference locations without the aid of a loop. 
Regards. Dan. 

 


Todd
 

Hi Gary and Dan,

I receive noon residual noon MW skywave from distances as short as 27 miles (44 km), for example 1692 KHz Radio Symban, Wedderburn. I can mainly hear 1575 KHz Wollongong at 50 miles via high angle skip during the day, but late evenings can only receive 1575 VOA Thailand, and Dunedin, NZ. The combination of high angle of incidence, and high radio frequency (e.g. 1575 KHz) is what it takes to penetrate the daytime D layer.

1566 KHz 3NE gets out better than expected. The station would be certainly surprised to learn that it reaches the Cook Islands.

1566 KHz 3NE is received into Melbourne via noon residual skywave. But there also days where there is no skywave. Peak D layer depletion is centered around the Winter Solstice (June 21).

Regards,

Todd
Sydney, AU


Dan Merta
 

Hi Todd. 

What equipment are you using to receive VOA Thailand and Dunedin NZ? Most interesting. There was a NZ beacon on 1692kHz years ago, & there is one still on 1630kHz you may be able to receive that at your location. 

Yes 1566 kHz 3NE does get out quite a long way than expected. I recall in the mid 1980s it would come into Melb very weak around and just after sunset, then disappear again about 1/2 hour later. Things changed in the early 90s when they upgraded their transmitter.

Regards. Dan. 


Todd
 

Hi Dan,

I mostly use the Sangean PR-D3 portable radio for its above average audio fidelity. It is the Australian equivalent of the C. Crane CCRadio-2E. The PR-D3 features 6 and 3 KHz switchable bandwidth.

The antenna is a 65 cm (26.5 inch) diameter PK loop mounted on the kitchen bench top. This is manufactured upon request by PK Antennas, Melbourne.

Geographic location (Sydney) may be the main contributor for me receiving 1575 KHz VOA Thailand, and Otago Access Radio Dunedin, NZ. Indeed there are times when it is easy to receive these stations using just the PR-D3 radio. But the loop makes the signal louder.

The 40 inch PVC box loop enables stronger signal reception compared to the 26.5 inch PK loop, but not always better signal-to-noise ratio. Some rooms in my house are RF quieter than others. The 40 inch loop is likely the general equivalent of a 5 inch FSL. Hence, there are various antenna and radio combinations that would adequately receive 1575 KHz VOA Thailand, and Otago Access Radio Dunedin, NZ at my location.

918 KHz Cambodia sometimes just fades over 4VL Charleville, QLD. This is a case of signal propagation being the main contributor.

610 KHz Vietnam produces a loud 2 KHz het when tuned to 612 KHz 4QR Brisbane. 

Regards,

Todd


Dan Merta
 

Hi Todd. 

I also have a PK loop antenna, purchased at a hamfest about 5 years ago, I find it very handy for listening to 675kHz ABC Corwa in the mornings. 

I can confirm VOA Thailand does get to Melbourne, after my last post I tuned in at 10.44pm Sat night and heard Music, and another station with talk. The music station came up above the talk and I clearly heard the VOA ident. This was with the aid of the PK loop. 
Afterwards I tried again without the loop & VOA came right up with the ident clearly heard again. I was lucky the ident was announced on 2 occasions while the station came in strong. The radio used was the Digitech AR-1780 which is my main dx unit atm.

918 kHz sounds like one I could try too, but there's a local station here on 927 kHz who's spatter will be a pest. 
Also we have a 50kw station 3RN on 621 kHz so 612 kHz is difficult to work with. 

This afternoon, about 3.30pm  some residual E layer skywave was taking place, 900kHz 2LT Lithgow was clearly heard, as was 1053 kHz 2CA Canberra. Also the usual ones near the top of the band. 1494kHz 2AY Albury, 1521kHz 2QN  Deniliquin and 1566kHz 3NE.

Regards. Dan.