AM and FM DX

I’m at Charlestown, my building is at a slightly higher elevation than Highpoint, so even though I am only 6 floors up, I am still 138 M ASL, with a perfect LOS south… Even on a clear day, I can see the Wyrrabalong hill upon which the Wyong DTV transmitters are on without binoculars, which is 53 kms away.

My building runs SW-NE, and it’s quite long, which means it’s difficult to get signals from the north.

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I live in Logan and there is nothing on 88.2. But there is Tourist radio on 88.0

No wonder you obtain such great results to the south. I would like to test an 8 element Yagi from your location, though I know it’s probably impossible to put one up on the roof. Do you have access to a balcony? Other enthusiasts have rested 3 element Yagis on strategically positioned tables outside of their apartment, with fairly good results.

Very interesting, didn’t think the penthouse headline was any great advancement, as you write, you’re already close to that.

How have you calculated the 138m ASL?

I do have a balcony, but it’s not deep enough for an 8 element yagi.

You’ve got me thinking about a 3 element one, that would probably bring about a worthwhile improvement over a pair of rabbit ears.

Well, I used Google Earth to get the street level elevation @ 120 M.

And then there are 96 steps each 18cm high (no, I didn’t measure every step! But they all look to be the same height).

And my DXing height adds close to another metre.

Have you got a GPS navigation that you can take out of the car?

Most have a height ASL reading you can see, look through the settings & take it out on the balcony.

I do have a TomTom Via 280 (I think)… not sure if it has elevation, but I’ll have a look.

Altimeter is what measures elevation.

A 3 element Yagi would provide much more gain than a simple set of rabbit ears. The hierarchy of antennae is roughly this:

  • Whip antenna (negative gain)
  • Rabbit ears (negative gain, a little better than a simple whip)
  • Dipole (0 dB gain, the ‘reference’ antenna. Will yield good results when conditions are suitable).
  • 3 element Yagi (several dB gain over dipole. The minimum requirement for exotic FM reception such as double hop E-skip and long distance tropo).
  • 8 element Yagi (several dB gain over 3 el Yagi, but not as much as 3 el Yagi>dipole. Recommended antenna for serious FM DX).
  • 15 element Korner Yagi (state of the art, several dB gain over 8 element Yagi, will readily pick up very weak signals such as pirate FM stations via E-skip. Recommended in rural areas. However, overload will probably be experienced in metro listening areas).
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I’m picking up a non-English station on 189 kHz on the LW band in Sydney. Does anyone what station this could be or can anyone else receive it?

A harmonic of SBS or a AM foreign lang narrowcaster?

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Speaking of harmonics, there is still a very strong one of ABC News on 774 in western Sydney.

My car radio picked this up via the “auto seek” function in Prospect, about 15 kms from the Prestons Tx site.

Live not far from the 3RN/3LO transmitter in Melbourne; the two harmonics on 1242 (3RN) and 1548 (3LO) are stronger than the signal from the other main AM stations

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Though when i wss in western Sydney, I did not see any harmonic of 702 on 1404, or of 630 on 1260 (which is right next to 2SM).

I don’t think there was one on 1152 either (2 x 576).
I probably wasn’t close enough to the Tx.

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That’s not a harmonic thought, that’s a phantom image, there used to be a strong one in Newcastle for the same reason, it’s still there but not as strong, It has been discussed in here before.

It’s due to a sum of the difference between 2 of the ABC frequencies, there’ll actually be 2 of them, one will project an image of the upper frequency station & one will project an image of the lower frequency station.

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I can get one on 1404 kHz from where I am. 1152 kHz shows up on some receivers, too. The Prestons beasties are super strong here due to a total riparian path in that direction.

I get heaps of Fox Melbourne Harmonics on one of the radios but never get them on the RTL-SDR…
It confuses the f%@ out me when i’m trying to DX.

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I checked all the medium-wave stations, but nothing matched what was on 189 kHz.

It’s coming from Iceland according to http://www.shortwaveschedule.com/index.php?freq=189