[Boatanchors] Screen Modulated AM

[rbethman]

It does not take more than a couple of simple paragraphs to explain this 
mode of AM operation.

It sure as heck does not require tuning to 400W then dialing down to 
100W and control the screen voltage in a multi-page explanation.

This is why the 2X = 3dB and all its discussion got over blown.

Here is an example, again, of simply doing it.  The readings of specific 
number of final mA grid current and the like are in the radio MANUAL!  
That is why they print them.

    To use a screen modulated radio with a linear amplifier, I.E., a DX-60 
    into an Amp Supply LK-500ZB:

    Tune DX-60 with the amp on standby.  DX-60 will get about 25W out.  Then, turning the DX-60 off of Tx mode, turn amp to ON from standby.  Put DX-60 to Tx, and rapidly, tune the Amp for max output.  Observe 
    output, (Power meter), to see what carrier level you have with the carrier ONLY from DX-60.  Ensure you have the "headroom" in the amp.

    A DX-60 will do around 25W itself on AM for a carrier.  Fed into Amp Supply LK-500ZB, the carrier when tuned for max will be about 300 to 350W carrier.

    Now the control for modulation is the audio level adjustment.  The DX-60 is on the chassis behind the panel.  The audio chain is what controls the screen levels.

That's it in a nutshell!

Bob - N0DGN