Given there’s only two stations licensed to 1053 AM - 2CA Canberra and SEN Track Brisbane - I’d suggest it’s a harmonic or signal overload
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Decent tropo this morning from Bung. Getting 96.3 Coast FM on the car radio as well as 91.6 Sydney. 93.3 2SNR also in, unless it’s just 2MNO. Koori has come up with RDS.
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I am on the other end of the Canberra duct.
Weak Classic, Triple J, and News Radio Canberra.
2XX just above the noise floor
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Better than usual reception of Triple M Warragul and national Latrobe Valley stations into Geelong this evening, also getting Flow FM from the Yarra Ranges which I don’t normally get
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I was down in the Illawarra this afternoon & at Windang, I could get the Eden FM services down there, including 103.9 Power FM, 104.7 2SEA & 105.5 2EC. 94.5 2EC & 102.5 Power FM from Bega had managed come in over FBi & 2MBS from Sydney respectively. 2BRW can be received there as well, which leads me to think that it’s permanent reception at that location.
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I wouldn’t imagine it would be permanent, I have tried for that at Flagstaff Point near the Wollongong CBD and I couldn’t get anything further south than Batemans Bay, so I think you may have just got a good catch!
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I think he means 2BRW is permanent and not Eden. Eden can often be received at Hill 60, Port Kembla- but it’s not permanent.
Braidwood is actually NW of Batemans Bay and of course is higher in altitude.
There’s a certain spot driving up the hill from Stanwell Park where Eden often comes in on 105.5 (and probably 103.9 now). You only need a sniff of enhancement. Yet reception of Eden just a little further inland is fairly rare.
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A very random question.
Given most FM stations transmit with mixed polarity, why are all dedicated outdoor FM antennas only designed to maximise reception on one plane and not the other? ie all elements are pointing the same way.
Most FM installations I’ve seen are nearly all horizontal ones, I don’t think I’ve seen any vertical ones.
Is it simply due to practical reasons in manufacturing, transporting and installing them?
So I gather you are referring to outdoor receiving FM BCB antennas?
If so there’s a few reasons for this.
Most receiving outdoor FM BCB antennas are only designed for receiving in one direction only as usually customer only interested in receiving transmission from the one tx site in rural/regional/remote areas.
Much cheaper to design for one direction only.
Most installations for outdoor eg Yagi/log periodic are mounted in horizontal plane. Several reasons for this:
- Easier to mount a horizontally orientated yagi on a vertical mast.
- Cheaper to mount vs vertical, as a vertical yagi requires a stand-off horizontal pole piece so metal vertical mast doesn’t hinder the radiation properties of the vertical orientated (pol) antenna (eg Yagi/LP).
The vertical metal mast does not usually affect a horizontally polarized mounted yagi antenna’s radiation pattern. - Noise or RFI is generally biased towards vertical polarization plane. Hence a horizontally polarized antenna will generally yield a better SNR (signal to noise ratio). This is important.
- Most average Joe TV antenna installers are naïve to FM broadcast polarizations of specific FM stations. Easy to mount horizontally.
There are several low powered stations or several stations only using vertical polarization for their TX antenna. In these cases it would be dumb to use a horizontal polarized receiving antenna as you would be potentially attenuating your received signal by 20 - 40dB.
In some countries they use slant or 45 degree polarization for tx antenna. In practice/theory a vertical or horizontal rx antenna can be used & only suffer a 3dB loss.
Hope this helps 
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As ozbark said for the rest, but not just some countries, we use them here in Aus. but I’m guessing what he means is a single dipole at 45 degrees slant left or right, not both like we use.
From here on, I’m talking slant both ways, like we mostly use here in Aus.
Most side-mount FM transmit antennas are 45 degree slant (depending on make & model), & quite a few sites have Panel antennas that are 45 degree slant elements, good for the exact reasons you mention, Horizontal or Vertical receive, only lose 3dB, but then you have cars with a slant antenna or a portable radio that people generally place the antenna in a 45 degree slant position don’t lose anything.
Slant transmit antennas will give a different radiation pattern to those which have Vertical &/or Horizontal linear elements, which in some cases will give better coverage using slant.
As @Radiohead asked the question, & something that is close to home for him, the KOFM, NXFM, & 2NURFM side mount antennas at Mt Sugarloaf are the slant type (NXFM antenna in pic), the master FM antenna on the BAI tower at Mt Sugarloaf for the ABC’s is also a slant (panel type, in pic), others such as the Commercial FM antenna at Artarmon & the main/standby FM antenna at Gore Hill are Vert./Horiz. panel antennas, (Artarmon in Pic).
NEWFM (not in pic) is a side-mount but is more of the horizontal/vert. type, unfortunately I don’t have a clear photo of the NEWFM antenna & Jampro don’t make that model anymore so I can’t like to it on a web page/photo.
Also while in Australia we say/licence services as being mixed polarisation, most antennas especially of the side-mount type (in the pic) are actually circular polarised antennas, & are called such in the rest of the world. Outside of Australia, you probably won’t hear anyone call an FM transmit antenna a mixed polarisation type.
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I’m wondering if you guys could help me out I brought a 2005 Holden VZ Calais over a year ago and when I first brought it I could pick up all Brisbane FM stations in Gold Coast/Tweed almost perfectly now I can barely pick up them up except for Nova and 97.3 nothing is damaged cause I checked I’m wondering what it could be?
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Sounds like a loose connection with your aerial?
Maybe an auto electrician can fix that.
Yeah I can pick up Gold Coast and Northern Rivers stations okay it’s just the Brisbane ones that aren’t as strong as they used to be
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Thanks @ozbark & @RFBurns for detailed replies. I lapped it all up, appreciated the depth and knowledge you have.
The reasons against vert pol then begs the question, why on earth is DAB+ flawed further with it only TX as vert pol?
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With 5MU off 1125 kHz, has night time reception of 1125 in eastern Australia improved for say 1RPH?
I wonder if 1125 from Radio Vanuatu in Port Vila is part of what can be received at night? Similar to AM 666 from Nouméa used to.
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I found out my reception problems with the Brisbane FM stations was caused by my FM bluetooth transmitter in my car
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No sign of it in Cairns at night. I wonder if it’s actually on air, or transmitting at very low power. Radio Vanuatu has FM transmitters as well as a SW service.
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Thanks @dxnerd, good suggestions, will email them sometime.
Coincidentally, their 7260kHz is audible, just above the noisefloor in Brisbane.
Doing a search on the bands in the backyard again tonight and ALL Melbourne FM & AM Stations coming through without any interference… Check the Tropo Index and there is bugger all tropo too… Could Traralgon East be a sweet spot for Permanent Melbourne Reception? Its strange because they’re supposed to have a null to the east. Oh well, I’m not complaining, no more listening to Gold 104.3 on iheart!
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These ABC Local Radio promotional cards look more appealing than the bland ABC Local stickers.
Now with a few mods they could also make nice QSL cards for the local ABC stations.
Front & rear sides of card displayed for one of the ABC local studio stations.
I didn’t know about the Nowra newsroom.
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