Some clarifications to my previous post:
I was using a 13.8v 50A power supply, well regulated.
I stated that the The output power on the 706 returns
to nominal after about 2.5 mS. That's 2.5 mS after the transmitter is
activated. The actual spike lasts a little over a millisecond.
The power levels were determined by reading the p-p voltage on the
scope (measured with an attenuator) and converting to watts. The
nominal power levels agree with my Bird meter.
>
>All this talk prompted me to take my storage scope home tonight and
>have a look at the rigs I use. Here's what I saw at 3.5 MHz as
>measured with a 2Gs/sec digital scope:
>
>On my Icom IC-706Mk2G, approx 1 year old:
>
>pwr spike overshoot
>=== ===== =========
>100w 100w 0%
> 75w 91w 21%
> 50w 73w 46%
> 25w 52w 108%
> 10w 26w 160%
>
>On my 9 year old Kenwood TS-850SAT:
>
>pwr spike overshoot
>=== ===== =========
>100w 109w 9%
> 50w 58w 16%
> 25w 30w 20%
>
>I didn't check my Johnson Ranger :-) Anyway, the 850 looks pretty
>good, about 20% is the worst case. The output power on the 706 returns
>to nominal after about 2.5 mS. I took some pictures, and if there's
>any interest I can put them on a web page for others to see.
>
>It would seem to me that the IC-706 (and rigs like it) would mainly be
>problematic with amps that require substantially less than 100w to
>drive and that switch quickly. Is this correct?
>73,
>Doug, K4DSP
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