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Old February 2nd 08, 07:54 AM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jul 2006
Posts: 232
Default 70cm reflectometer?

Owen Duffy wrote:
Do Australian TVs use "Bloody Belling Lee" connectors like we still do
in the UK? What does "PAL" stand for?


Yes, the TVs invariably have the Belling Lee connector, now known as
the PAL connector. I don't know how it got the PAL label, perhaps
related to its use in the UK where PAL colour encoding was used (as it
is here in Oz).


OK, that makes sense.

[ Incidentally, for anyone who hasn't seen the 'alternative' meanings
for the various international color TV standards:

NTSC (USA) = Never Twice the Same Color
SECAM (France) = Something Else, Contrary to American Methods
PAL (rest of western Europe, Australia and NZ) = Perfection At Last. ]


Apparently the PAL connector was invented in 1922 and complies with BS
and IEC standards.

Or rather, the standards had to comply with the connectors, because the
connectors were there first.

I did some tests on BL connectors in the seventies and performance up
to 2GHz was better than UHF connectors, and quite acceptable. The BL
connectors that I tested were plated brass bodied male connectors with
soldered centre pin, and plated steel bodied female connectors (all in
good condition).

That's fine... now try again with the much more common aluminium bodied
plug, and a centre conductor wire that was pushed into the centre pin 20
years ago, was never soldered and is now heavily tarnished.

That unsoldered 'maybe-connection' inside the centre pin is a major
cause of poor reception and TVI in the UK... along with water in the
coax, which has an interesting effect when the water reaches the
aluminium/copper connection inside the plug body. The whole thing is a
classic example of insane design.

Modern practice is to install F connectors in fixed wiring.


Much better, as those are specifically designed to be solderless.



--

73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek
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