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For Crystal Palace`s broadcast frequencies see its Channel Allocation Guides for
before and after the DSO. These also include the same information for most of the
other major transmitters receivable within the coverage area of Crystal Palace, i.e.
Sandy, Sudbury, Bluebell Hill, Dover, Tunbridge Wells, Heathfield, Reigate, Midhurst,
Guildford, Rowridge, Hannington, Oxford and Hemel Hempstead. This data can be of
great use in determining possible causes of co-
how most of the broadcast channels from the various transmitters “Dovetail” together
but it has not been possible to eliminate potential co-
output (e.g. for a Sky box or CCTV system) to be added to your TV setup/distribution
system without suffering from co-
Ofcom report significant transmission restrictions from East round to South on all six
digital MUXES, analogue is more or less omnidirectional, certainly the first 4 channels.
DSO is due to occur in 2012 (possibly in April) and unsurprisingly it has been confirmed by Ofcom that Crystal Palace will stay an A group at DSO when its
digital power output will go up from the present 20kW to the post DSO 200kW.
Crystal Palace is transmiting a pre switchover low power HDTV MUX (on CH31 at 10kW)
from December 2009. Due to co-
significantly restricted to the SE, just like the other digital transmissions. Furthermore Sandy, Reigate and Rowridge all transmit on CH31 so it is not unknown to have problems receiving the HD channel even if all the other MUXES are fine. In any event you will
obviously need a new Freeview HD set top box which were on sale from Spring 2010.
As mentioned above the channel planners were able to fit all the Digital / Freeview MUXES in the A group along with the existing analogue stations so an aerial change may well not be necessary. Furthermore those in poor reception areas, who may require an upgrade, can take advantage of the superior performance of an A group aerial over a wideband. In fact such is the widebands inferiority at the bottom of the band that there is no such thing as a “High Gain” wideband aerial for the A group frequencies and nobody should ever fit a “high gain” wideband on an A group transmitter, e.g Crystal Palace.
If the site is in a poor spot an A group aerial should be used. On the other hand if the signal is strong (or medium) then by definition it doesn`t need a “high gain” antenna anyway ! Under these circumstances a Log Periodic should be fitted instead.
See Crystal Palace transmitter`s graph and the wrong aerial for Crystal Palace.
For Crystal Palace we recommend the DM log for strong signal areas, the Log 40 for medium signal areas, the Yagi18A for outside installs in poor signal areas,
the XB10A for loft installations in poor signal areas, and the XB16A for those with the
most marginal signals. Unless you have a massive loft we`d normally recommend the XB10A over the XB16A for a loft install due the smaller size of the former aerial
The dimensions and test performance of the aerials can be found on the relevant tables.
See Crystal Palace`s height in relation to other transmitters.
Picture Justin Smith (ATV)
The frequencies given are for the analogue channels, for (most) digital MUXES add 3MHz.
Note the gaps in the table below for channels 31 to 35, 37, 39 to 40 and 63 to 68, they`re reserved for “other uses”....
Those situated to the North or NW of Crystal Palace may find that during certain
weather condition they can suffer from co-
In the old 405 line VHF days the transmitter only broadcast the BBC and a second similar design (152m in height) was constructed in 1962 for ITV * at Croydon. When UHF started transmission in the 60`s (1964 from Crystal Palace) the distinction between BBC and ITV broadcasting sites was discontinued and everything was transmitted from Crystal Palace.
In fact in 1985 when the VHF signals were finally switched off it seemed Croydon`s days as a TV transmitter were over. However this was not quite the end of the story because when Channel 5 began broadcasting in 1997 Croydon was given the job of transmitting it (also at 1000kW) to the London area. Although Crystal Palace does not transmit analogue C5 the vast majority of those receiving their signals from it will still pick up C5 perfectly well because it`s within group and Croydon is only 1 mile away to the SSW !
That said, the word is that analogue C5 is severely attenuated to the S/SE, possibly to
avoid co-
In any event Digital C5 (on MUX 3) is broadcast from Crystal Palace.
* This double transmitter scenario was also used for Sutton Coldfield / Lichfield,
Emley Moor / Holme Moss and Pontop Pike / Burnhope amongst others.
The site gets its name from the original Crystal Palace which was built for the Great Exhibition (of 1851) and moved to this site in 1854, unfortunately it was tragically destroyed by fire in 1936. Also located near the tower is the National Sports Centre of 1964. For years this housed London`s only 50m swimming pool (until a second one opened in Ealing) but it also has various sports halls plus the the well known athletics track.
External links
Crystal Palace transmitter page on MB21
from France
Crystal Palace transmitter`s channels in relation to the TV band and the gain of the aerials we recommend for it. DM Log Log40 Yagi18A XB10A XB16A
Also see other relevant A group curves.
Spectrum = Interleaved Spectrum Channels
Some post switchover MUX allocations will be changed due to the 800MHz clearance.
If you`ve found this site informative and, hopefully, interesting as well,
There are two interleaved spectrum channels allocated to Crystal Palace, CH29 and CH42.
It will be noted that CH 29 is within the previously announced Post DSO group but CH42 is not. However the latter frequency will have co channel issues with at least three other transmitters so its power and radiation pattern will be severely restricted. The proposed radiation pattern for this particular interleaved frequency (from the Ofcom Document) is shown below right. I`m not an expert on interpreting these but as far as I can tell only
those to the East and the NNW would stand any chance of getting it ! Under these
circumstances, together with the fact it will be out of band for the great majority of the
aerials within its coverage area, one wonders who would actually pay much for it !
Those who want the option of this (possible) MUX should fit the Log 40 or the XB16A if in a poor spot. Group A aerials fitted after the mid 1990s (when the group was extended from CH34 up to CH37) may well receive CH42 in strong signal areas.
The proposed transmission pattern for the CH29 interleaved frequency is shown below
left and it is far more omni directional.It must be remembered that all these radiation
patterns may be subject to change due to the “800MHz clearance”, and if the frequencies
change so do the co-
Proposed interleaved spectrum channels for Crystal Palace.
These are the wrong aerials for Crystal Palace (or any other A group transmitter).
(see Crystal Palace graph)
Both these aerials were spotted in Purley On Thames, just West of Reading, and they`re
both on Crystal Palace transmitter which is about 40 miles away. The thing is, they`re the
wrong aerials for Crystal Palace, or any A group transmitter come to that.
I`m not familiar with the signal strength in this location (though the one on the left was on
a bleedin` high pole....) but whether it`s a strong or weak area the installer has still fitted
the wrong aerial.
Why ?
Well if it`s a weak reception area an A group aerial should have been used.
On the other hand if it`s a strong or medium reception area he should have
fitted a Log Periodic aerial,
Let`s assume it`s a weak area. I estimate that over the Crystal Palace frequencies the
aerial on the left would average about 1.5 dB more than a DM Log and the one on the right about 2.0 dB more. But if you`re short of signal a Yagi18A would give about 4.7 dB more, and an XB16A about 6.7 dB more. We had a customer who was shielded from Crystal Palace transmitter by the Arsenal football stadium. He originally had a DAT75 but his pictures were very poor, so he swapped to an XB16A and reported that whilst his signal wasn`t perfect it was much better, “we can actually watch TV now” was his exact comment ! QED #1
Now don`t get me wrong, I`m not saying these wideband aerials aren`t working for these particular installations. Let`s be honest if it`s a decent signal area they`ll work fine.
But the fact is that on Crystal Palace there would be a minimal performance difference between one of these huge wideband aerials and a Log40. The latter performs just as well
as any wideband Tri Boom antenna, yet has much less wind loading, is still be a wideband and has all the advantages that a Log Periodic aerial offers. QED #2
The thing is a Log40 is smaller than a Tri Boom so some installers find it harder to justify their (large ? ) bills..... Any connection ? Or am I just getting cynical as I get older ?
In my opinion if any installer tries to sell you this type of Tri Boom aerial for Crystal Palace
(or any other A group transmitter) you can quote me that he’s fitting the wrong antenna.
Although I think Tri Booms are over rated (particularly for frequencies at the bottom of the band) it`s possibly a little unfair to pick on them because all of the comments in this article apply (to a large extent) to any wideband Yagi type aerial, whether X Beam or not.
But all Tri Booms are wideband so at least I can be sure what I`ve photographed !
experience problems, e.g. with certain MUXES disappearing. First try rescanning your
TV / set top box (do it manually if possible), but if this fails to work check on transmitter work
or call the reception advice phone numbers. Also see basic digital fault finding.
Crystal Palace transmitter is situated 6 miles South of The Tower Of London, though it was built rather more recently than the latter, in 1950. The tower is 222m high (see How High is High ? ) and in some ways looks similar to the Eiffel tower in Paris, although the French structure is taller at 318m. I have often wondered why the owners of Crystal Palace don`t learn from their Parisian counterparts and build a public viewing platform. I`m sure they would recoup the investment many times over, after all it`s far higher than, say, “The London Eye” ! There`s probably some Health & Safety B******s ruling to stop it.....
Crystal Palace transmitter`s population coverage is unsurprisingly the highest in the UK at around 11 million and it is also one of the most powerful transmitters in the country at 1000kW (analogue power) and 20kW (digital power). Crystal Palace transmits a horizontally polarised signal and it was, is, and is due to remain, an A group transmitter.
The transmitter has fifty six smaller relays of which 8 are horizontally polarised which could be important to bear in mind if you are trying to confirm which transmitter you are on !