Foxing out a Foxtel installation

I recently received a handwritten work order from the managing agents of a block of 12 units, stating that the antenna amplifier in the basement needed urgent replacement. According to the order, it was ruining all the Foxtel reception.

Now I had never been to this address before and knew nothing about it. I tried phoning the agents but the man in charge wasn’t available. In the end, I decided that as I had been contracted to do the job, I might as well see what I could do.

When I arrived, I discovered that the block was a security building to which I had no access except to the basement. Inside, I could find no sign at all of a distribution amplifier, nor any trace of one ever having being there. There was, however, a Foxtel amplifier.

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The distribution amplifier was probably up in the roof (which would make more sense), so I drove to the managing agent and obtained the key. Back at the units, I finally got into the roof area but there was no amplifier there either. There was, however, ample evidence to show that there used to be one because there was an empty box for one and there were cable fittings for one to be installed. Fortunately, I managed to talk to a long-time resident of the block who was pretty cluey and he told me that there used to be an amplifier there but it had been removed many years ago.

He also told me that what was now in place at the units was a Foxtel Satellite System that had been installed privately except for the dish and LNB which had been fitted by Foxtel. It had been running successfully for a few years but had failed about two months earlier and several previous technicians had called but had failed to fix the problem.

Now the story I had previously been given had a certain ring of truth about it, as it is not uncommon for a distribution amplifier to interfere with Foxtel transmissions. That’s because most technicians invariably run free-to-air transmissions and Foxtel on the same line through this amplifier. A faulty DC power supply can thus introduce hum bars into the distribution amplifier and severely affect the Foxtel signal, sometimes to the extent that it prevents the decoder from working at all.

However, in this instance, there was no distribution amplifier and unfortunately, I am not all that familiar with the Foxtel satellite system. For starters, I don’t know the satellite channel plan or what sort of levels to expect, nor do I have the correct signal level measuring equipment.

Fortunately, I managed to borrow the correct meter from a colleague although I wasn’t initially all that confident as to how to drive it. However, having familiarised myself with the gear, I checked the signal level output from the Foxtel amplifier to be 75dB, which is not enough for a 12-outlet building. As a result, I picked up a new Foxtel satellite amplifier (identical to the original unit) from my wholesaler, along with a generic spare and an 18V power supply.

I connected the brand new Foxtel amplifier, only to find it was DOA (dead on arrival) – faulty straight out of the box! I then fitted the new generic amplifier and set its output for 100dB. That done, I went to one customer’s unit and measured 70dB at his outlet which is perfect for Foxtel. But there was still no Foxtel.

Foxtel use horizontal and vertical polarisation in their systems, controlled by the power supply, ie, 12V = vertical and 18V = horizontal. The question was, which one was being used? I tried the 18V power supply I had with me but no go, so I went back to my friendly wholesaler and picked up a 12V power supply. It made no difference so I left the original 18V power supply in place.

Foxtel also uses two local oscillator frequencies – 11.3GHz and 10.7GHz – to match the appropriate LNB, so that was the next thing to look at. I managed to get the locked Foxtel security code (set-up menu 0611) to get into the service menu and changed the local oscillator from 11.3GHz to 10.7GHz.

At last – perfect pictures! It was then just a matter of going around to all the other Foxtel owners and readjusting their menus in the same way.

When the job was completed (all in the same day), I had time to reflect on what had probably happened. When the original fault occurred, there was a lot of miscommunication as to what the problem was and too many different technicians got involved.

The cause was actually the Foxtel amplifier but a previous technician had changed the LNB on the dish for one with a different local oscillator frequency and didn’t replace the original when he found it made it worse – probably because he was told to just change it and didn’t have time to check the result.TCL widescreen TV