[ICOM] IC-756 Pro II Power Output Change

[Larry Young]

I absolutely agree with all that you said Roger.  The point is, his radio is putting out 100 watts. He may have other issues with his station equipment.
Larry, K4LXV

--- On Fri, 9/23/11, K8RI <k8ri at rogerhalstead.com> wrote:

From: K8RI <k8ri at rogerhalstead.com>
Subject: Re: [ICOM] IC-756 Pro II Power Output Change
To: icom at mailman.qth.net
Date: Friday, September 23, 2011, 1:18 AM

On 9/22/2011 5:20 PM, Larry Young wrote:
> Thomas, if you get 100 watts pep output when you whistle into the microphone, on ssb, then your rig is indeed putting out 100 watts pep. At a single tone, PEP and average power are equal If you drive your mike input with two equal tones and measure the output power in each tone, they would equal 50 watts each, but the total output = 100 watts by adding the total of the two output output tones.
>     Depending on your voice chacteristics and your microphone response you may not see much indicated power out on the wattmeter. This is a function of the type of wattmeter you may be using. A very accurate pep wattmeter or an oscilloscope measurement of the RF voltage across the 50 Ohm dummy load will reveal the truth. Believe me, your rig can indeed put out 100 watts pep on ssb.

I'm looking at this a bit differently.  He stated the output *changed* 
from what it was putting out.
Regardless of whether it can put out 100W carrier with a whistle, or how 
ever, running the same setup as it was before the output is now less 
*apparently* under the same conditions. That should not happen unless 
something changed.  Antenna, coax, mike, measuring equipment.  If it's 
all the same as it was originally then it should read the same. Of  
course antennas and coax are notorious for changing. Coax fittings go 
bad, coax goes bad (I found a piece with a hole in the jacket).  I've 
had rotator loops go bad, I've had paper wasps build nests in matching 
networks which not only messed up the network, but the wasp "goo" got 
into the coax connector, went through the connector and also ruined the 
connector on the coax and about a half a foot of coax. I've had other 
antennas interact with the "known good antenna" rendering it "not so 
good". I've had head sets/mikes go flaky too and I've had SWR meters get 
strange including some very expensive ones. I've also had finals develop 
a harmonic. They still showed full power into a dummy load, but all of a 
sudden the output power was down going to the antenna and the SWR was 
up, but the antenna looked good on an analyzer.   In over 50 years on 
the air I've had about anything that can break, do so.  This is ignoring 
intermittents<:-))

73

Roger (K8RI)
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