[Amps] Ampleon BLF189XR 1900W LDMOS transistor

[Paul Christensen]

>"It's about time the FCC imposed  2.8 KHz bandwidth limitation with a
requirement that *all* products outside the required bandwidth be suppressed
by at least 30 dB (preferably 40 dB) plus 10*log(PEP/100) above 100 W "

That would preclude use of most legacy gear we've been using for a long
time.  It would be an enviable goal for new product, however.  

Although I'm not a fan of bandwidth regulation, Canada created a
well-thought bandwidth plan that allows for variable bandwidth by band of
operation.  For example, their RBR-4 regulation (previously RIC-2) sets a
maximum bandwidth on 80m/40m of 6 kHz, independent of mode, followed by the
following restriction:  "The bandwidth of a signal shall be determined by
measuring the frequency band occupied by that signal at a level that is
26 dB below the maximum amplitude of that signal."  On the 30m, the maximum
bandwidth is 1 kHz.  

Today, we can achieve much better than -26 dBc.  However, if the U.S.
imposes a strict bandwidth on "all emission products" for voice, then
arguably, we need a coordinated effort with Canada and many other "strong
signal" countries to follow.  For example, here on the east coast, there are
times when Canadian and EU stations are stronger than many U.S. stations on
20m -- and greater in number.  During those conditions, a U.S. bandwidth
limit may only be of moderate help, especially when strong, non-U.S.
stations exceed a 2.8 kHz voice bandwidth.  

Paul, W9AC