I've installed a fishbone on top of the roof. I've got two tvs in different rooms. When connecting the antenna cable to each tv directly, it works fine, so we bought a tv splitter. It's a basic one: http://www.dicksmith.co.nz/antennas/ds-tv-2-way-right-angle-splitr-dsnz-cn3507
However, when we split it to two tvs, one one gets reception and the other one doesn't. Our house is in on top of the hill and can see the reception tower, so the signal should be strong.
Any ideas how I can make this work?
I've got a similar setup except my signal is in the shadow of Mt Kaukau, so the signal gets very marginal very quickly. You may be getting strong signal to the aerial, but from there it has to get to the tv's and so on. Aerial wire can get very lossy very quickly, and splitters tend to make it worse.
The analogy most people use is the hose... the longer the hosepipe, the weaker the water pressure. Add multiple taps and the water pressure drops etc.
You've said that when you're directly connected, then both tv's work fine. So passively splitting the signal (which is what you're doing) means there isn't enough to drive both. That means:
1. Shorten cable lengths from outside aerial to point of split or if possible replace the cable run with very low loss new wiring. I'm guessing that's not an option though :-)
2. Install a low strength active signal booster as close to the aerial as possible (which means you need some sort of ac power source close by). Hills Signalmaster or similar
3. Call a tv guy to help