Ive got a Kings aerial standard with a Knaus moho, has anybody upgraded as the reception seems to be pretty limited.
dabbler said
07:54 PM Nov 1, 2020
TV antenna need to match the transmission plane/polarity, horizontal or vertical.
Before changing anything else, do you have an app or other means to determine which plane is used for a given location and can your existing antenna be adjusted for a given location ?
Warren-Pat_01 said
09:59 PM Nov 1, 2020
Do a 360 degree scan, then if you can change the polarity of the aerial & do another scan.
If you're near others with tv reception, ask how their's is & set yours the same. There might be a problem too with the aerial feed into the van - is it accessible?
Also there may be an amplifier in the line - it could be switched off. There is an old saying "KISS" - we all fall for it sometimes!
Mike Harding said
07:46 AM Nov 2, 2020
I have a top of the range antenna and pre-amp ($800!? Came with the new van) nevertheless I have found reception of digital TV to be very erratic and requiring a good signal much more so that was the case with analogue TV. Currently I am located 6.5km across flat ground from a 40W TV repeater at 30m elevation and I cannot receive a signal channel (polarisation is correct). I suspect the 600MHz signal is largely being absorbed by the forest between me and the Tx, good job I'm not a TV watcher - although I do miss BBC World Service radio on channel 303.
hufnpuf said
08:23 AM Nov 2, 2020
Mike Harding wrote:
and requiring a good signal much more so that was the case with analogue TV. Currently I am located 6.5km across flat ground from a 40W TV repeater at 30m elevation and I cannot receive a signal channel (polarisation is correct). I suspect the 600MHz signal is largely being absorbed by the forest between me and the Tx
Yes, that's right. With analogue you would still have reception even if it was weak. With digital you get NOTHING until your signal is at a certain level. The other thing is that there can be too much signal. The solution to reception problems isn't always signal amplification, sometimes you need an attenuator or to switch off any amplifier. At a fixed residence, an antenna guy has to mess around once to give what the location needs, trying to get optimal signal while going from location to location can be very difficult. OP, you may need to fiddlefiddle with any antenna, unfortunately they aren't "set and forget" so try to get the correct polarity, as suggested and point the antenna in the correct direction. Do the fiddlefaddling before you replace the antenna because the problems may not be down to the antenna.
The strength of your tv tuner can also play a big role. Some tuners are better than others.
(off-topic to Mike Harding)Can you get World Service on a shortwave radio? Do you have one? Do they even sell them any more?
Warren-Pat_01 said
12:06 PM Nov 2, 2020
hufnpuf,
I carry a comms receiver with me - have used it on Radio Australia in the past but heard a year ago that Sheparton had closed down.
I haven't tried listening to other stations for a while so I can't say if they are still operating.
These HF stations were not cheap to operate as most were of relatively high power (RA at Darwin, Radio Canada) were both 250Kw but RA is now defunct & buried (would have been worth a bucket or two in scrap metal (stainless steel, aluminium, copper & brass).
They needed bundles of money (govt support, donations, etc) to keep them going.
All radio transmissions operate similarly - the higher the frequency, the more direct it works e.g.
VLF, LF (<30Khz - 300Khz) mainly travel under water (submarines)
MF (300 - 3000Khz) our normal AM broadcast above ground, partial sky waves depending on time of the day
HF (3 - 30Mhz, what we know as short wave) bounces off various layers of the ionosphere - giving it the desired ranges - hence having to change frequency as the hours tick by.
VHF (30 - 300Mhz) is more line of sight but some bouncing occurs at lower frequencies.
UHF (300 - 3,000Mhz) are more line of sight transmissions
SHF (3,000 - 30,000 Mhz). When the MLC building was built in Adelaide several decades ago, a then PMG tower had to be shifted to enable a radio bearer to continue to operate between My Bonython to Waymouth Xge.
And Mike, wet leaves in a growing rain forest attenuate radio waves more.
Mike Harding said
07:06 AM Nov 3, 2020
>And Mike, wet leaves in a growing rain forest attenuate radio waves more.
I'll bet - wet trees play havoc with GPS reception at 1.6GHz too.
I know a guy who use to do the comms for large car rallies and he had a special licenced frequency in the 70MHz region because he found it penetrated forest *much* better than the more commonly used higher frequencies.
Have you considered going for an Amateur licence Warren? I suspect you would enjoy the hobby.
>(off-topic to Mike Harding)Can you get World Service on a shortwave radio? Do you have one? Do they even sell them any more?
You sure can buy domestic short wave receivers - Sony still make then and I'm told this Tecsun SSB unit (A$275) is good:
I have an advanced Amateur Radio licence so generally use an Icom IC-7300 30kHz-70MHz transceiver and an 80m off-centre fed antenna for short-wave listening - a very nice SDR radio and well priced at A$1700.
Unfortunately (and foolishly, just like ABC) the BBC have significantly reduced their short-wave transmission of the World Service. It is possible to receive the Indian and African signals in Oz but you will need a good antenna (wire in the sky) a telescopic whip won't suffice.
This reduction in world broadcasting by BBC/ABC and others has left the door open for China to spread their culture/propaganda and there are *many* Chinese stations on the bands.
hufnpuf said
08:00 AM Nov 3, 2020
Mike Harding wrote:
Unfortunately (and foolishly, just like ABC) the BBC have significantly reduced their short-wave transmission of the World Service. It is possible to receive the Indian and African signals in Oz but you will need a good antenna (wire in the sky) a telescopic whip won't suffice.
That's a shame, when the internet disappears, they'll be wanting to put it all back in. I have a (Sony) radio that has shortwave (I think). It's only a small radio though, I doubt you could use it otherwise than somewhere with a transmitter/repeater close by.
Warren-Pat_01 said
04:26 PM Nov 3, 2020
No, Mike,
Have too many hobbies now - bird watching, astronomy, tripping, gem stone collecting, cutting, fishing (rare these days), etc.
A couple of blokes that I worked with who were HAMs put me off it years ago - besides working at it was enough! Thankfully work increased the number of channels I dealt with from one to high capacity fibre optic.
When I first went to Darwin (Radio Australia), my first job was Mon& Obs, where we had a number of RA freqs to monitor & rate, as well as some other overseas stations. Of course we quickly go sick of flicking past the Voice of America in the Philippines (at the height of the Vietnam War). The receivers were high quality Racal units with all sorts of flash filters on them.
The comms receiver I have is the more expensive Jaycar one. Perhaps that's where a couple of extra kilos of weight that I forgot about - my long wire!
Derek Barnes said
06:21 PM Nov 4, 2020
When our TV reception gets bad while caravanning we use a portable VAST satellite TV antenna and receiver. We used it on our last trip when the reception at Nyngan was poor. The portable satellite antenna was out in the middle of an enormous downpour which lasted hours but the reception was good all through the storm. The only hiccup occurred when a gum leaf landed on the satellite dish and stopped the reception until I removed it.
Phillipn said
11:25 PM Nov 4, 2020
Derek Barnes wrote:
When our TV reception gets bad while caravanning we use a portable VAST satellite TV antenna and receiver. We used it on our last trip when the reception at Nyngan was poor. The portable satellite antenna was out in the middle of an enormous downpour which lasted hours but the reception was good all through the storm. The only hiccup occurred when a gum leaf landed on the satellite dish and stopped the reception until I removed it.
Heavy rain and thick clouds will interfear with satellite reception for both VAST and Foxtel.
Derek Barnes said
07:52 AM Nov 5, 2020
Actually as I said in my post the reception during the storm using the VAST system was perfect.
Mike Harding said
01:20 PM Nov 5, 2020
Derek Barnes wrote:
Actually as I said in my post the reception during the storm using the VAST system was perfect.
You were lucky.
As, no doubt, will be another 50 posters who'll assure me rain, hail, clouds, fog or pestilence has never affected *their* TV signal :)
Ive got a Kings aerial standard with a Knaus moho, has anybody upgraded as the reception seems to be pretty limited.
If you're near others with tv reception, ask how their's is & set yours the same. There might be a problem too with the aerial feed into the van - is it accessible?
Also there may be an amplifier in the line - it could be switched off. There is an old saying "KISS" - we all fall for it sometimes!
I have a top of the range antenna and pre-amp ($800!? Came with the new van) nevertheless I have found reception of digital TV to be very erratic and requiring a good signal much more so that was the case with analogue TV. Currently I am located 6.5km across flat ground from a 40W TV repeater at 30m elevation and I cannot receive a signal channel (polarisation is correct). I suspect the 600MHz signal is largely being absorbed by the forest between me and the Tx, good job I'm not a TV watcher - although I do miss BBC World Service radio on channel 303.
Yes, that's right. With analogue you would still have reception even if it was weak. With digital you get NOTHING until your signal is at a certain level. The other thing is that there can be too much signal. The solution to reception problems isn't always signal amplification, sometimes you need an attenuator or to switch off any amplifier. At a fixed residence, an antenna guy has to mess around once to give what the location needs, trying to get optimal signal while going from location to location can be very difficult. OP, you may need to fiddlefiddle with any antenna, unfortunately they aren't "set and forget" so try to get the correct polarity, as suggested and point the antenna in the correct direction. Do the fiddlefaddling before you replace the antenna because the problems may not be down to the antenna.
The strength of your tv tuner can also play a big role. Some tuners are better than others.
(off-topic to Mike Harding)Can you get World Service on a shortwave radio? Do you have one? Do they even sell them any more?
I carry a comms receiver with me - have used it on Radio Australia in the past but heard a year ago that Sheparton had closed down.
I haven't tried listening to other stations for a while so I can't say if they are still operating.
These HF stations were not cheap to operate as most were of relatively high power (RA at Darwin, Radio Canada) were both 250Kw but RA is now defunct & buried (would have been worth a bucket or two in scrap metal (stainless steel, aluminium, copper & brass).
They needed bundles of money (govt support, donations, etc) to keep them going.
All radio transmissions operate similarly - the higher the frequency, the more direct it works e.g.
VLF, LF (<30Khz - 300Khz) mainly travel under water (submarines)
MF (300 - 3000Khz) our normal AM broadcast above ground, partial sky waves depending on time of the day
HF (3 - 30Mhz, what we know as short wave) bounces off various layers of the ionosphere - giving it the desired ranges - hence having to change frequency as the hours tick by.
VHF (30 - 300Mhz) is more line of sight but some bouncing occurs at lower frequencies.
UHF (300 - 3,000Mhz) are more line of sight transmissions
SHF (3,000 - 30,000 Mhz). When the MLC building was built in Adelaide several decades ago, a then PMG tower had to be shifted to enable a radio bearer to continue to operate between My Bonython to Waymouth Xge.
And Mike, wet leaves in a growing rain forest attenuate radio waves more.
>And Mike, wet leaves in a growing rain forest attenuate radio waves more.
I'll bet - wet trees play havoc with GPS reception at 1.6GHz too.
I know a guy who use to do the comms for large car rallies and he had a special licenced frequency in the 70MHz region because he found it penetrated forest *much* better than the more commonly used higher frequencies.
Have you considered going for an Amateur licence Warren? I suspect you would enjoy the hobby.
>(off-topic to Mike Harding)Can you get World Service on a shortwave radio? Do you have one? Do they even sell them any more?
You sure can buy domestic short wave receivers - Sony still make then and I'm told this Tecsun SSB unit (A$275) is good:
Tecsun PL880
Also consider the Degen brand available on eBay.
I have an advanced Amateur Radio licence so generally use an Icom IC-7300 30kHz-70MHz transceiver and an 80m off-centre fed antenna for short-wave listening - a very nice SDR radio and well priced at A$1700.
Unfortunately (and foolishly, just like ABC) the BBC have significantly reduced their short-wave transmission of the World Service. It is possible to receive the Indian and African signals in Oz but you will need a good antenna (wire in the sky) a telescopic whip won't suffice.
This reduction in world broadcasting by BBC/ABC and others has left the door open for China to spread their culture/propaganda and there are *many* Chinese stations on the bands.
That's a shame, when the internet disappears, they'll be wanting to put it all back in. I have a (Sony) radio that has shortwave (I think). It's only a small radio though, I doubt you could use it otherwise than somewhere with a transmitter/repeater close by.
Have too many hobbies now - bird watching, astronomy, tripping, gem stone collecting, cutting, fishing (rare these days), etc.
A couple of blokes that I worked with who were HAMs put me off it years ago - besides working at it was enough! Thankfully work increased the number of channels I dealt with from one to high capacity fibre optic.
When I first went to Darwin (Radio Australia), my first job was Mon& Obs, where we had a number of RA freqs to monitor & rate, as well as some other overseas stations. Of course we quickly go sick of flicking past the Voice of America in the Philippines (at the height of the Vietnam War). The receivers were high quality Racal units with all sorts of flash filters on them.
The comms receiver I have is the more expensive Jaycar one. Perhaps that's where a couple of extra kilos of weight that I forgot about - my long wire!
When our TV reception gets bad while caravanning we use a portable VAST satellite TV antenna and receiver. We used it on our last trip when the reception at Nyngan was poor. The portable satellite antenna was out in the middle of an enormous downpour which lasted hours but the reception was good all through the storm. The only hiccup occurred when a gum leaf landed on the satellite dish and stopped the reception until I removed it.
Heavy rain and thick clouds will interfear with satellite reception for both VAST and Foxtel.
Actually as I said in my post the reception during the storm using the VAST system was perfect.
You were lucky.
As, no doubt, will be another 50 posters who'll assure me rain, hail, clouds, fog or pestilence has never affected *their* TV signal :)
Nevertheless, it does.