[ARC5] AM modulating an "ARC-5" transmitter...

Fri Oct 9 21:44:20 EDT 2015

On 10 Oct 2015 at 12:16, Brian wrote:

> Hello Ken,
> 
> Does that 60 W PEP mean 30 W fixed carrier and 15 W per sideband max when 
> modulating?

As I understand it, the fixed carrier can be set to almost anything you wish it 
to be set to, including zero. Total power output under modulation cannot be 
more than the rated plate dissipation of the tube(s), which in this case for a 
pair of 1625s is 60 watts.

I'm sure that value is a combination of the carrier and the AF. I don't really 
know any other way of explaining it.

> How is that different from what the ARC-5 Tx can achieve?

As far as I am concerned, there isn't any difference.

> Or are you 
> suggesting that CC modulation will give higher fidelity of the modulated 
> signal?

No. Not that either. The reason I am suggesting CC modulation is simply 
because it does not require any modulation transformer, nor high-voltage, 
nor large tubes, and can be implemented with two 9-pin tubes and minimal 
circuitry.

> I would be interested in trying out your ideas.

Me too. :-)

Ken W7EKB