Yep, you are right.  way back when, we use to rate rigs on input power. 
I had an af 67 which ran one 6146 and on am it was rated 600 watts 
input.  I don't know what the output was, didn't have a way to measure 
it.  I never checked swr either.
73
Butch
WA0VJR
Node 3148
Wallace, ks.


On Wed, 6 Jun 2012, Lloyd Rasmussen 
wrote:

> It will depend on whether those final amplifier tubes are running in Class
> AB1, AB2, or B.  This depends on the idling plate current vs. the key-down
> plate current.  Higher efficiency (lower idling current, operating the tubes
> closer to cut-off) increases the distortion of your signal, which is
> unimportant for CW but quite important for SSB.  I would guess that you are
> talking 50 percent efficiency (ratio of power output to power input).  Not
> all of the enpower is lost in the tubes, though.  A little of it is also
> lost in the pi network output circuit.  I would probably adjust the plate
> tuning and loading controls for maximum power output and leave it at that.
> I assume you're not trying to run this station remotely.
>
> Lloyd Rasmussen, Kensington, Maryland
> Home:  http://lras.home.sprynet.com
> Work:  http://www.loc.gov/nls
>
>> -----Original Message-----
>> From: For blind ham radio operators [mailto:[log in to unmask]]
>> On Behalf Of Michael Ryan
>> Sent: Wednesday, June 06, 2012 6:44 AM
>> To: [log in to unmask]
>> Subject: Plate dissipation VS output power
>>
>> Hi all:
>>
>> Is a rule of thumb to compare plate dissipation to actual output power?
>> IE: My FT-102's 3 6146s can safely dissipate 105W between the 3, 200w out
>> on SSB and 160 CW. So if I'm running my max CW, whats the plate
>> dissipation of the tubes?
>>
>> TNX & 73:
>> Michael De VO1AX
>>
>> Sent from my iPhone
>
>