If you think that TV installation's complex don't look into an attic over here in Cork, Ireland!

In the days before BBC 1 & 2 were carried on SKY digital
Co. Cork was exclusively served by a few systems (operated by a monopoly cable company):
Cable in the city and larger towns.
MMDS in the non-urban areas.

(ITV/C4 still are not on the Republic of Ireland's SKY package..the irish terestrial channels are on 101-104 and BBC 1/2 on 214/215 so cable/mmds are still the only legal ways of receiving ITV or C4)

However, MMDS coverage isn't exactly universal and the company who operates the cable and mmds systems tends to be pricy and seem to have employed ex-gestapo agents as customer service people!

The result was that during the 1980s a community owned and operated UHF rebroadcasting system was established (without a licence) to rebroadcast BBC 1, BBC 2, ITV and C4 from overspill signal picked up on the east coast (130 miles away). The system picked up the UK broadcasts on a huge tower antenna and beamed them back to a network of distribution TX's around the county. Since cutting off people's favourite TV channels goes down like a lead balloon in an election, not to mention the fact that the TV community group inserted help messages after popular programmes like coronation street to rally the "troops" (community tv campaigners) to come out and march if anyone dared to raid their facilities [Linked Image], the system has been allowed to continue to operate as long as it respects the frequency allocations used by RTE and other broadcasters. However, I suspect that the advent of full "freeview" digital terrestrial type TV here will be the end of the line for the rebroadcasting system.

Anyway, back to the point:

RTE 1 / Network 2 broadcasts on a mix of VHF and UHF
(along with TV3 and TG4 only on UHF)

Southcoast community television broadcasts 4-5 channels on UHF
(for years this included sky one and eurosport!!!)

So the average house has 2 flat panel wideband (UHF/VHF) antennas on the roof pointing at different transmitters.

Using a completely weird mix of diplexers, filters and attenuators tuned to filter out unwanted signals the feeds from the two antennas are merged into one cable and usually fed from there to a distribution amplifier feeding at least 3-4 (if not all) rooms in the house. It would be quite common to add a door security camera on UHF, maybe the feed from the VCR/SAT box too !!

Our antenna installers tend to have to be able to resolve all sorts of ghosting, crosstalk, patterning, weak signals, etc etc.. [Linked Image]

Basically you have:

2 X antennas (with inline amplifiers on the pole)

feeding through all the attenuators etc..

the internal stuff (sat boxes, door cameras etc) is added in.. possibily more attenuators if there are problems with interference / crosstalk.

then on to the distribution amp..

it can get as complicated as a mini-cable tv system! [Linked Image]

Generally analogue reception is excellent though!

ITS COMPLICATED [Linked Image]


[This message has been edited by djk (edited 07-31-2003).]

[This message has been edited by djk (edited 07-31-2003).]