Tubes (was OT: Televisions)

Alexander Schreiber als at
Tue Feb 16 20:06:27 CST 2010

On Tue, Feb 16, 2010 at 07:14:55PM -0600, Randy Dawson wrote:
> There is no shortage of tubes, boh new, and NOS.
> Sovitek and Svetlana make copies of all common audio tubes.  No guitar player uses solid state equipment.  Emic still rules the high power RF world, as there is not a semiconductor substitution for a TV / Radio transmitter final output yet.

Having visited a transmission tower for Swisscom Broadcast this week,
this isn't true. IIRC their setup no longer uses tubes, but is all
semiconductors. But instead of one big high power tube handling 10 kW
peak power by itself, they use parallel amplifiers and mix their output
to get up to the required power levels. Their current setup, while
handling way more channels, only uses a (rather) small fraction of the
space previously used by their old tube based setups. That particular
tower transmits DVB-T, DVB-H, DAB and UKW. It also has space for
several GSM/UTMS BTS and a bunch of microwave links - all in 185 m
of tower. A pretty impressive place.

Kind regards,
"Opportunity is missed by most people because it is dressed in overalls and
 looks like work."                                      -- Thomas A. Edison

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