TV Masthead Amps

[Citroënbender]

Q: Are these a WOFTAM? Trying to help a friend renting in an area with poor TV reception due to steep terrain and ongoing high rise construction all ‘round. Just wants the usual Sydney channels, nothing more.

Have got a couple of antennas to play with, a panel type and a regular form. Neither can get all channels in dry weather, and inclement conditions worsen this to one or two only, even with careful alignment. Working budget for hardware about $120.

[.:4:.]

Are you pointing the aerial in the right direction? For sydney the tv towers are in chatswòod. If you dont have test equipment, easy trick is to look at the direction the tv arials on the other houses point.

[Citroënbender]

Yes, absolutely. Even a couple of degrees off will make the difference between number of channels it receives OK.

[.:4:.]

Matchmaster do do head amplifiers. Its probably a better bet to go to jaycar and pick up a gme unit.

[Itsme]

Installing digital antennas is not like the old analogue where you point in direction and that is it, sometime just the location of the antenna will not be suitable due to nearby interference.
Usually, an antenna installer will test for the best location on your dwelling.

[Citroënbender]

Being a rental, my hands are somewhat tied. I’m sure the ideal installation would be a massive mast, probably well over six metres, with the antenna on top.

There’s an existing mast of about 3,6m I can attach the antenna to, and a suitable GPO for inserting power.

[JasonACT]

I've had good success with Kingray, so not a waste of time. But still, I've got a PC that has 3 x dual tuner devices (can tune in 6 channels at the same time - and report signal level and quality) which really helped me get my antenna in just the right spot.

Quality on 1 channel always droops when it's raining though (only occasionally gets bad enough to notice - and I think when that happens that's at the transmitter end - which I suspect has its own rain water leakage issues).

[Citroënbender]

OK, got myself a 15W Kingray masthead and a PSK06 power injector. Now it’s raining - no time to channel Tevye. :(

Does anyone here know if the passive setup will still (vaguely) function if I do the underfloor stuff (power injector install) in advance? Not turning it on, just wiring it in.

[.:4:.]

You talking about the power amplifier that goes into the coax and plugs in?

[Citroënbender]

This part:

https://www.kingray.net.au/au/power-supplies/psk06f/

I presume they just supply a DC voltage and “backflow” is prevented/filtered. Just didn’t know if there was a physical connection inside.

[.:4:.]

I wouldn't waste the time putting in the roof, under the house or wherever. Just put it behind the credenza the tv sits on and plug it in.

[Citroënbender]

There’s a three way splitter under the house, so it needs to go before that. TVs are variously wall hung, sat on a dresser and up on a bedroom shelf.

Also, the last antenna install was done using a 10m prefabricated cable, which is not long enough to allow full height on the mast. The amplifier means I can use a 3m cable from antenna, then the previous 10m cable, so no straining of the wires.

[.:4:.]

If its just a splitter, it doesn't matter which side the signal amplifier connects to. If its a reducer, then yes, that matters.

[Citroënbender]

Pretty sure it just says splitter on it. I’ll look today.

[JasonACT]

Originally Posted by Citroënbender

There’s a three way splitter under the house, so it needs to go before that.

Correct, if you don't, then 2 of the 3 TVs will be fed power causing real problems.

But, at the same time, this extra detail will be why the signal is so rubbish. You should have got a Kingray with 1 aerial input and 4 outputs - and replace the passive setup. Even if the Kingray isn't installed on the mast, but instead under the house, it will give you much better results.

And no, don't install the power injector before the amp is installed. You will short circuit it with the existing connection to the antenna - or at least have a 75 ohms short, which is really not good at all. Even if not turning it on, it'll most probably ruin your reception.

[Citroënbender]

Thank you (again!).

I knew there was a reason I didn’t watch TV. :-/ All this effort to fill one’s mind with an on-demand alternative to life outside.

I’ll press on with my current pieces, it’s close to maxing out the budget as it sits. The fancier Kingray parts were quite a bit dearer.

[JasonACT]

Worth a try. These things are made to solve this issue though (and yes, they get expensive, but without it you're only working with one third the signal). Also, don't discount the idea that the passive splitter is cactus (I've had that before) so it's worth bypassing it when setting everything up, if you have the right connector, so only 1 TV is wired to the aerial.

[Citroënbender]

Yes, I purchased an F type joiner so that it can be tested on a single output only.

The real problem is massive amounts of high rise going up in the 20-odd kilometres between the transmitters and this site, and where signal in the lee of a decent hill was once passable, it’s no longer the case.

[Citroënbender]

Result.

All channels now working. Thanks to the AFF tech team for advice I could build on.

[zilo]

In case it deteriorates again...If you rotate the aerial at 90 degrees to the horizontal it will focus extremely accurately (and will need to be firmly fixed), we have done this in Hobart when site is more than 50km from the transmission tower and fresnel effect from hills etc.