"Richard Clark" wrote in message
Hi Tam,

You missed the point. 100 Watts PEP is not 100 Watts continuous (such
as your computation leads to).
............................................

Hi Richard,

The voltage swing at the collector can only go between roughly ground a
2*VCC. For a continuous wave it does that for every cycle of the RF signal.
For SSB, it only reaches that on voice peaks, but it can get no larger.
Although you will be on the ragged edge, you can tune up a pi network linear
on a constant tone, and operate with speech.

BTW, did you notice the 174 Ohm Zo of the MRF450. Clearly, you can't
conjugate match that. I am convinced that is a real number, and not a
conjugate of load number. They do not give any min or max limits on this. I
looked at some small signal transistors, and found that Ro can vary by more
than an order of magnitude from unit to unit.

I think that virtually all current HF ham transmitters are push pull, and
use feedback. That will affect the output impedance.


We have all been quoting Motorola literature. I am going to look at what
Philips, and the Japanese have to say on this.

Tam/WB2TT