[TenTec] Final Amplifier Class

[John Huggins]

Ladies and Gentlemen,

I frequently contribute technical knowhow to a CB trucker's forum 
(before you press delete please read on).  The question came up 
concerning my assertion the single final transistor amplifier, typical 
in CB transmitter output circuits, operates as a Class A amplifier since 
the modulation required is AM and sometimes SSB, both being amplitude 
style modulations, and both desiring of good linearity in the 
amplification (at least I think so).

I know for sure CB output circuits are not push pull since they have 
only one power amplifying transistor.

Some are suggesting the less than 180° Class C amplification method is 
what CBs use.  I understand this requires a good tank circuit to 
complete the sine waves, but is supposedly inappropriate for amplitude 
style modulations like AM, DSB and SSB.  Various resources suggest Class 
C is fine for CW and FM.

I am sure by now you are saying "That's interesting John, really, but 
what does this have to do with Ten-Tec?"

Well, I suddenly remembered some advertisement for an HF Ham Transceiver 
that offered Class A mode in its output circuit for some improvement in 
some parameter.  Funny thing is I guess I thought Ham Transceivers 
always used either Class A with a single device or, perhaps, Class AB or 
B in a push-pull arrangement.

What I need to know from Tec-Tec and/or any of you is:

- What is the final amplifier class (A, AB, B or C) used in, say, the 
Ten-Tec OMNI VII and/or Orion II?
- Is it actually possible to use Class C with an amplitude modulation 
scheme like AM, DSB and/or SSB?
- In a good ol' Ten-Tec linear amplifier is the final Class A?
- Do most Ham Transmitters utilize pairs of power devices in a Class AB 
or B in a push-pull arrangement?

Hopefully this will fine tune my EE knowledge of circuits and make sure 
I have not missed something I should know so I can continue to represent 
the ham community well when offering advice to the other radio groups.

Thanks for your help.

John
KX4O