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.
Items Covered This Month
TFW76BO3 76cm widescreen CRT TV
42WP48A plasma TV
L32M61A7 LCD TV set
Latitude D600 notebook computer
Ford Falcon XE
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
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
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