> -----Original Message-----
> From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On
> Behalf Of Steve Thompson
>
> Dammit - I wish I could find the plots I did of the 'risetime' out of my
> IC706IIG to publish. I'll have to take a fresh set. From memory,
> 150% for a
> few ms, then zero for 200ishms then about 20ms risetime to levelled power.
> Never seen the like of it - all bands, all modes.
>
I keep hearing how bad the 706 is - I don't know if there's a difference in
TX overshoot between the 706, 706Mk2, and 706Mk2G. I had a look at mine back
in January of this year. Here's what I wrote back then:
==========
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%
==========
This was on CW. At 100w it seems to be a non-issue, but at lower power
levels the overshoot shows up. What I did not see was the 200 mS (or ANY)
period of zero output. TX overshoot I can believe, but I'd certainly suspect
that something is wrong with the radio if it went back to zero output for
200 mS. I would think that you'd hear it on CW, and nobody complains about
the CW signal from my 706.
I have pictures of the above if anyone is interested.
73,
Doug, K4DSP
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