> In the 2 meter amplifier after a 3 minute CW transmission at about 20
>wpm
>into a dummy load, the average anode exhaust temperature went from 205
>degrees F
>to just under 100 degrees F when using the EBS.
This is the aim.
EBS seems to have a poor reputation because of either:
1. Being the only means of keying the amplifier, which is guaranteed to
cause hot-switching. Competent EBS works along with the hard-wired PTT
line - it cannot replace it.
2. Being RF-actuated at too high a level (ON4UN suggests around 0.5W in
a kW amplifier, related to the dynamic range of he speech processing for
SSB).
3. Being too slow to turn on.
Any or all of the above can cause a poor signal, and then of course
there's:
4. Being unreliable and easily damaged.
... but it doesn't have to be that way.
Like many other features in amplifiers, EBS can be very useful if it's
competently done - or a disaster if not.
--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'
http://www.ifwtech.co.uk/g3sek
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