My measurements of a couple of Japanese radios that do allow 40 watts of
carrier in the AM mode does conclude that the positive modulation peaks are
only about 70% to 75% modulation while the negative peaks approach 100%.
Their modulation is not very symmetrical. Therefore they yield about 100
watts PEP output.
The Omni VII that I have does a nice symmetrical job of modulation on AM
while the Paragon II did not fare quite as well. The Omni VII modulation
envelope is almost as good as my old Heath Apache and the RCA BC
transmitter. The Omni VII output is between 22 and 25 watts of unmodulated
carrier and with 400 Hz tone modulation the PEP measured output is 90 to 100
watts.
73
Bob, K4TAX
----- Original Message -----
From: <wa3fiy@radioadv.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Sunday, September 30, 2007 4:37 PM
Subject: Re: [TenTec] ten tecs have 100 watts out on carrier??
> Jerry did answer the question very well but let's try another approach.
>
> Using a 100 watt max power rig as our base, no SWR foldback, no circuit
> breaker tripping,
> the rig can produce a max of 100 watts to a 50 load. That is 70.7 volts
> of RF to the 50 ohms.
> That's (70.7 X 70.7) / 50 or 500/50 or 100 watts. On CW that's fine but
> what about AM? On
> AM we must reduce the carrier to 1/2 voltage or 35.35 volts. Using
> P=E(squared) divided by
> R, that is 35.35 X35.35 = 1,250. 1,250 divided by 50 ohms = 25 watts. So
> the carrier power
> is as Jerry stated, 25% of the max power available. On AM modulation, the
> carrier voltage
> swings from the 35.35 volts with no modulation to 0 to 70.7 volts under
> full modulation.
> Hence, the instantaneous power varies from 0 watts to 100 watts under
> modulation. I have
> noted some of the import rigs rate AM carrier at 40 watts out. Don't know
> how they do that
> without creating clipping under full modulation. I guess maybe they do
> not allow 100%
> modulation. Anyone know for sure?
>
>
> 73,
>
> -Lee-
> WA3FIY
>
>
> On 30 Sep 2007 at 16:59, john ferro wrote:
>
>>
>> actually you have not helped me out - you still have not answered the
>> question - whats the difference between an am carrier and cw carrier? if
>> it's the same as some people say why on a japanese radio the am carrier
>> is only 25 to 50 watts (depending on the radio) when the mic is keyed vs.
>> 100 watts on the same jap radio cw mode keyed down - all assuming swr is
>> 1? i understand the swr fold back issue.> From: OTAKEBI@aol.com> Date:
>> Sun, 30 Sep 2007 16:39:52 -0400> To: tentec@contesting.com> Subject: Re:
>> [TenTec] ten tecs have 100 watts out on carrier??> > Yes, Mike.> Now we
>> know what was going on once he explained it a little better.> I had a TS
>> 180s that at had to see a perfect, flat, SWR to put out full > output.>
>> Like Ten Tecs better.> Glad we were able to help him.> Dan/N4VET> > > >
>> ************************************** See what's new at
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>
>
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