Scanning from inside buildings

[gkoutlis]

All;

While at work I can't seem to get the FESA channels. But as soon as i go outside - they pick up perfectly - close to 100%

What can i do to get the FESA channel while i am indoors at work, While i am at home there is no issue - being in south perth its actually pretty good.

I would appreciate any response or comment to help here.

[meg]

Which channels are you talking about - 6AR/6IP or the area channels ?

[gkoutlis]

Those especially Meg - definatley 6AR/6IP - My desk at work is right next to a window with no interference with antennaes or anything.

[meg]

Strange - I'm in an office in Perth next to a window and have no problem picking up 6IP and the area channels. Can't get simplex, but that's understandable...

I've heard of buildings where the spacing of the metal frame was such that it blocked particular frequencies - the only suggestion I could give in that case would be to run a cable to an antenna outdoors - a bit extreme!

Others might have better ideas though

[gkoutlis]

Thankyou for the idea and the thought - i appreciate it.

[vk6hgr]

Frequencies at around 79Mhz are poor at penetrating buildings. High-band VHF (166Mhz or so) and more so UHF (like the police on 468Mhz) do a much better job.

This is the reason why FESA are keen to move away from 79Mhz. It has excellent range generally but poor building coverage.

Plus, scanner antennas are hardly efficient at 79Mhz. A proper quarter-wave antenna would be a piece of wire about a metre long

[vk6hgr]

Frequencies at around 79Mhz are poor at penetrating buildings. High-band VHF (166Mhz or so) and more so UHF (like the police on 468Mhz) do a much better job.

Just been doing some searching about this and UHF has greater loss in dense trees and forests than does VHF. Makes me wonder why FESA are keen to go to UHF...

[Brian]

One of the things you will also find with scanning inside a building is the fact that because there is so much concrete and metal and other communications (data in cable etc.) floating around you that even though you might be next to a window and it helps reception a bit, the tower you might want to listen to could be on the other side of the building so the signal is getting blocked by the building itself.

In a tall building it can obviously be a bit of a problem putting an antenna up sometimes (especially outside), but you could look at some of the new antennas on the market which are a patch antenna. Laser makes a few of them, but mainly only for 800 MHz and UHF. Nothing specific for VHF. There are a tuned sticker basically that just sticks onto your window (car, house, boat, 134 th floor, etc.) and then couples to your radio. Much better than an onglass antenna because there is a physical connection between the antenna and the scanner.

I can supply more details of these if anyone is interested.

Regards,

[gkoutlis]

Brian - Welcome on board - Thankyou for your very helpful information, I suppose i will just have to live with it for the moment.

Thanks also to you too vk6hgr!

[JG-103]

Brian, so how do these stickers work and how much? Do they improve frequencies that you normally pick up well? JG103

[Brian]

Essentially the stickers are just that. A sticker. What makes the sticker special is the fact that it has a tuned antenna running in it made from a metal similar to that on the back windscreen for the demister. In fact there are some covert cars around that use exactly this for an antenna (The demister wires on the rear windscreen), they do need to be tuned up though and I wouldn't recommend just connecting the scanner to the demister.

Anyway, the wires in this sticker are pretty thin and silver which pretty much makes them see through. They come in a number of different bands and can be put almost anywhere. Not recommended to be put over demister wires. The only bad thing about the antennas is basically once they are on, there is no getting them off and moving them to another point.

How much are they? All depends exactly what you want. Have a look in the store here for some examples. Some of the initial pictures are cloudy for some reason but if you click for a larger picture it comes good.
http://www.emcom.com.au/store/view_prod ... _clear-474

Here's another one for cellular applications
http://www.emcom.com.au/store/view_prod ... =Laser_707

Panorama Antennas also makes some active antennas for windows that are a little more obtrusive because they are not clear, but work just as well if not better than the Laser antennas. An example is here.
http://www.emcom.com.au/store/view_prod ... PAN_EF-422

Of course these are just three examples I picked off the top of my head and all around the $40 - $50 mark so they are not too expensive. All depends how long you are planning on making use of it I suppose.
There are a number of other similar and completely different antennas in the Antenna category listed below. Some of the Panoramas are fantastic and have been designed especially for those European cars with the antennas in the roof. Pull the old antenna out, and stick the Panorama combination antenna in. All sorts of combinations of Two-Way, Cellular, GPS, AM/FM and more.
http://www.emcom.com.au/store/index.php ... e=Antennae

Regards,

[Fastlane]

Frequencies at around 79Mhz are poor at penetrating buildings. High-band VHF (166Mhz or so) and more so UHF (like the police on 468Mhz) do a much better job.

Just been doing some searching about this and UHF has greater loss in dense trees and forests than does VHF. Makes me wonder why FESA are keen to go to UHF...

.. only UHF in the metro area. High-band VHF will be used in regional areas.

[Brian]

I'm in no position to speak about the way these networks are set up because I have nothing to do with them. What I can comment on though is how a number of Government Agencies in NSW have just spent years changing all of their communications to One band. The SES is one that I have been involved in. Over the last Seven years we have spent massive amounts of money ditching all of the old UHF, VHF, and HF systems that were all over the State. Basically you could have a large operation in an area and get heaps of out of area crews in and no one could communicate with each other because we all used different band radio equipment.

Now we have one platform (UHF), with some HF still remaining in remote outlying areas. Pretty much the entire State is now covered with UHF radio coverage and most of the relative areas are all linked together.

The NSW Police are going down the same path slowly getting rid of their VHF system and going to UHF across the entire state. This once again means any car can go anywhere and there is no need for a dual fit in border area cars. Currently we have Blue Mountains cars on UHF and Lithgow cars (10 mins away) on VHF. Neither of them have each others radios and they have a lot of territory where they need to co-operate if there is a big accident. This means that two different radio centres at opposite sides of the State need to ring each other on the phone to communicate what the cars that are often 150 metres away from each other want to tell each other.

Makes a lot of sense really........ NOT!

Regards,

[vk6hgr]

Now we have one platform (UHF), with some HF still remaining in remote outlying areas. Pretty much the entire State is now covered with UHF radio coverage and most of the relative areas are all linked together.

Strange thing is, the WA police actually have a state-wide UHF network on the standard 64 channels. They're now changing it so country keeps analogue UHF and the city go to digital.

I've heard the new city radios will be able to also operate on 468Mhz the entire exercise seems to me to be a colossial waste of time and money...