BBC Hong Kong relay - a visitors view

BBC Hong Kong relay - a visitors view

Post by Richard Buckb » Tue, 10 Sep 1996 04:00:00

Hello Folks,

         It has been an ambition of mine for some time to visit Hong
Kong and with the hand over to China of this last British Asian
territory in July next year, I thought it was about time I went!  My
wife Sue visited her brother out there last year and returned full of
enthusiasm and loaded down with shopping!  She also broke her journey in
Dubai and said that it looked to be an interesting place, so we decided
to spend a couple of days there on the way out.

         We had a very nice flight to Dubai with Emirates Airlines and
after an interesting stay there, flew on to Hong Kong.  When we left
Manchester the temperature was 61 degrees F, in Dubai it was a "mild"
106 F and Hong was a mere 90 F but hyper humid - you get a free sauna
this time of year - just stand in the street!

         I knew that the BBC HF relay station in Hong Kong was due to
close in the next few months and being an ex-BBC transmitter man, I was
hoping to visit the site before it was too late.  The station is
actually called the "East Asia Relay Company Limited" and the company
manager and the only expatriate BBC man there is Miles Ashton.  I had
exchanged e-mails with him before leaving the UK and when I got to Hong
Kong I telephoned him and arranged a visit.

         Getting to the site is interesting, the location is at Tsang
Tsui in the far west of the New Territories and quite an isolated spot
not served by Hong Kong's excellent and very cheap public transport
system. Although we were staying in Kowloon and an overland journey was
possible, Miles suggested that the best route was by hovercraft!  My
wife and daughters evinced little interest in visiting a transmitting
station so I left them shopping, took the hotel bus to the famous "Star
Ferry" for the 10 minute ride over to Hong Kong Island, then walked
along to Pier 5 passing the huge construction site where the new rapid
transit station is being built.  The hovercraft go every 15 minutes to
Tuen Mun and it is quite a long journey, around 24 km. and takes about
35 minutes and is one of the more expensive ferries, all of HK$ 19,
which is about US$ 2.70 !

         Hong Kong harbour is remarkable, it resembles a maritime
freeway with vessels of all shapes and sizes running within feet of one
another and with hovercraft and hydrofoils dodging through the gaps in
between, I have never seen anything like it.  We set off and until we
could get out of this traffic jam we had to behave as an ordinary boat
and this particular vessel is obviously not designed for low speeds.  I
began to be thankful I had eschewed a cooked breakfast, as it would soon
have made a re-appearance!  We eventually got up to speed and the ride
became smoother.  Our route took us through the Ma Wan channel under the
huge new bridges that will connect the new Chek Lap Kok airport with
downtown Hong Kong.  We arrived in a flurry of spray at Tuen Mun, one of
the new towns built to house the territories booming population.

         I called Miles from the pier and lurked on the roadside,
getting odd looks from passers by, as Europeans seem to be rare in these
parts. Miles collected me and we headed off to Tsang Tsui.  He pointed
out a new power station being constructed on the coast and told me that
the road to the station was fairly new and before its construction, a
lengthy detour around the north coast was required.

         We seemed to arrive very suddenly at the station - having been
used to many acres of "aerial farm" at places like Woofferton and
Ascension, I was very surprised at the compactness of the site.  To the
south, big hills start immediately behind the aerial field.  However, a
glance at the map made the reason obvious.  The station was set up
basically to get signals into China, the coast of which is visible only
5 or so miles away.  To this end, the only direction of interest is
North.
        The reason for the huge amount of real estate at most short wave
sites is so that aerial arrays can cover many different directions.  At
Tsang Tsui there are just 5 towers in a line running East - West and
slung between them are 4 band arrays all pointing North.  The bearings
of the arrays can be electrically "slewed" some 14 degrees either side
of their natural beam heading.  There is no requirement to beam south
(there is nobody there!) so a simple curtain of horizontal wires acts as
a reflector.

         The arrays are fed with some very impressive 50 ohm coaxial
feeder which terminates under each array, where it goes into a balun to
convert it to 300 ohm balanced feed up to the dipoles.  All switching,
slewing and frequency changing is performed by the central computer in
the station which has the station schedule programmed into it, although
manual over-ride is possible.  One unusual feature of the aerial field
is a small temple where one of the staff regularly lights joss sticks.

         The transmitters are two Marconi 250 kW units which take up
remarkably little space and are designed for unattended operation.
Indeed the station is only staffed from 9 to 5 Mondays to Fridays.  If a
problem is detected outside these hours, a fault reporter unit auto-
dials the "Transmission Operations Centre" (TOC) in Warwick, England.
The TOC is manned 24 hours and they then place an overseas call to the
unfortunate engineer in Hong Kong whose turn it is to attend!  There is
a night watchman on site but he is not supposed to touch anything!  I
met his dog who is very friendly and probably not much use as a guard
dog, Miles tells me that he pays for the dog's food, so that probably
makes the pooch a BBC employee!

         The transmitters are interesting in that they employ Pulse
Width Modulation (PWR) rather than the high level modulation that used
to be the norm. PWR means that on modulation peaks the transmitter power
actually falls, the system relies on the AGC in the listener's receiver
recovering the signal.  I tuned into the signals from Hong Kong and
switched off the receiver AGC and it does indeed sound very odd.  The
use of PWR results in a big saving in electricity costs compared to
conventional systems.

         The programme feeds to the station go from Bush House in London
to the British Telecom ground station at Madley in central England, up
to the satellite and are received at Hong Kong Telecom's ground station
at Stanley on Hong Kong Island.  A fibre optic cable brings them to the
station.  The World Service in English stream (Green Network) is also
used to feed the RTHK Radio 6 medium wave transmitter on 676 kHz.

         Apart from Miles, the other engineers on the station are local
and are employees of Hong Kong Telecom under contract to the BBC.  I got
there just in time for lunch and was invited to share a "proper" Chinese
meal with them cooked on the premises.  Miles has grown used to chop
sticks during his 3 year tour but I failed miserably and to ease my
discomfort the station's solitary fork was produced!  I regret to report
that most of our other meals in HK were at MacDonalds!

         The station runs with an air of quiet efficiency and Miles
described his job as being akin to lighthouse keeping.  Indeed with the
sea only a few metres away and ships passing his window, I could see
what he meant.  However, change is on the way very soon.  It has been
known for some time that with the handover to China would mean that the
station had to go and this is one of the reasons for the building of the
new station in Thailand.  First transmissions are due in the next few
weeks and once the station is up and running, it will take over from
Hong Kong.  Miles did not have a definite date for this to happen,
sometime in October is probable.

         When the station closes, the terms of the lease are that the
site must be returned to its former state, effectively a green field.
This means that Miles has the awesome task of supervising the
dismantling and shipping of the transmitters and technical equipment
back to the UK.  The towers have to be taken down and the neat building
flattened.  A melancholy task indeed.  Miles reckons that by March next
year there will hardly be a sign that the BBC were ever there.  He
thinks that the engineers working for HK Telecom will still have a job,
but the other staff, including the dog, face redundancy.

         I noticed on Miles' desk several reception reports, mostly from
Japan but one very long and wordy one from Germany.  He tells me he is
happy to reply to them but asks that they be kept brief and to the point
and of course return postage in the form of an IRC is appreciated.  So,
if you want Hong Kong confirmed, you had better hurry!

         The address of the station is:

East Asia Relay Company Limited,
Tsang Tsui Broadcasting Station,
Nim Wan,
Tuen Mun,
Hong Kong.

FAX:  2474 6603

         As I bounced back across the bay in the lurching hovercraft I
reflected that if it was not for politics, life could be so much
simpler!

         I would like to thank Miles very much for taking the time to
show
me his fine station before it is consigned to history.




 
 
 

BBC Hong Kong relay - a visitors view

Post by Richard Buckb » Sun, 15 Sep 1996 04:00:00


Hello Folks,

        Further to my article about BBC Hong Kong earlier this week, I
have received the following message from Miles Ashton, the company
manager:-

==========

Richard,

Pleased that you got back safely.  I hope that your credit card bill =
isn't TOO huge!

Things have developed since you were here.  Our last broadcast isn't =
certain yet but will probably be at the end of November.  I'll let you =
know.

Regards,

Miles

========

        So it seems that you have bit longer to log the station before
it is demolished.  I think that the Thailand relay which will replace it
is running a little late.

(In case you are wondering - yes my credit card bill WAS rather large!

        The address of the station is:

East Asia Relay Company Limited,
Tsang Tsui Broadcasting Station,
Nim Wan,
Tuen Mun,
Hong Kong.

FAX:  2474 6603