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Mixing Austar Rf Into Distribution System


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#1 clipper

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Posted 27 March 2012 - 08:31 PM

Customer has 3 outlets for FTA. needs 6. Has two regular Austar boxes. Wants to send Austar to another TV on patio.
I said I can send Austar to all TV FTA outlets around the house, should be able to send austar RF from both boxes to all outlets.

Since ch levels are low 37-44 db at existing 3 outs I'll put in a wideband amp in roof cavity just below antenna. Band 3 feed off antenna (Mt W, Hobart) and UHF feed from PAyTV RF into the amp. The two RF feeds will be mixed before the amp with a Band 5/1-4 mixer and put into the UHF side of the amp, attenuated with gain control. The band 5 feed will be on CH 69, the Band1-4 feed will be adjusted on the second Pay box to Ch35. Reckon this should work. There are no UHF translators in the area. Any thoughts?

Edited by clipper, 27 March 2012 - 08:41 PM.


#2 M'bozo

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Posted 28 March 2012 - 07:16 AM

Keep it simple.

Masthead amplifier with separate UHF/VHF input.

VHF input for the big hill.

Run cables from the RF output both Austar boxes to a point near the antenna.

(I'm assuming they are not Mystars, you did mention they were regular boxes. Mystar standard boxes have to be done differently.)

Combine both RF outputs of the Austar boxes in a reverse 2 way splitter, using an attenuator on the output of the splitter (or use a tap of suitable value in reverse), to drop the signals to around 50dBµV (to keep the RF PQ at an acceptable level), and feed this into the UHF input of the masthead amplifier.

Have the RF out on the boxes at leat 3 channels apart - I use channels in the range 60-68.

Adjust the masthead gain controls for suitable levels at the outlets.

Watch for aspect ratio problems if the slave TVs are 4:3 versions.

#3 Tazzy2Heads

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Posted 28 March 2012 - 10:16 PM

Customer has 3 outlets for FTA. needs 6. Has two regular Austar boxes. Wants to send Austar to another TV on patio.
I said I can send Austar to all TV FTA outlets around the house, should be able to send austar RF from both boxes to all outlets.

Since ch levels are low 37-44 db at existing 3 outs I'll put in a wideband amp in roof cavity just below antenna. Band 3 feed off antenna (Mt W, Hobart) and UHF feed from PAyTV RF into the amp. The two RF feeds will be mixed before the amp with a Band 5/1-4 mixer and put into the UHF side of the amp, attenuated with gain control. The band 5 feed will be on CH 69, the Band1-4 feed will be adjusted on the second Pay box to Ch35. Reckon this should work. There are no UHF translators in the area. Any thoughts?

Hi Clipper,
I guess there is a reason why you didn,t do plan 'A' , Austar to the one tv with a wireless A/V sender. M'bozo is on the money
with his post. Watch the levels and all should be good, I have done a few jobs over the years before AV senders became a
reasonable price sending FTA overseas tv or Christian tv and VCR RF output via high channel
UHF signals to other tvs and everything was ok just using a 2 way splitter in reverse to feed into the system. Band 4/5 diplexers I've found are not to
common off the shelf and splitters seem ok to do the job.
Cheers Tazzy.

#4 clipper

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Posted 29 March 2012 - 07:18 AM

Band 4/5 diplexers I've found are not to
common off the shelf and splitters seem ok to do the job.


Just that I have a couple of diplexes in the van, only reason why I said I'd use one. Have used splitters in reverse on other jobs but then remember reading somewhere that a diplexer is somehow 'better'.

#5 nbound

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Posted 30 March 2012 - 04:25 PM

Johanssen do a 0-69 and 0-69 diplexer, good for mixing all kinds of things.

#6 andrewlace

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Posted 19 June 2012 - 08:02 PM

diplexers have far better isolation and lower insertion loss. For your application: mixing two analogue feeds they should be more than adequate. This is fine for analogue. Make sure that the channels are more than three channels apart and check for noise at the antenna and post amplifier before choosing an appropriate channel for the modulators (amplifiers do create noise) and it is worth checking to find free channel space.