Still looking for some pointers and/or advice on current AM
transmitter design.

One place where VHF AM is still alive is radio foxhunting (RDF).
The comments I've seen in the group so far are filament-based,
hardly usable for a portable transmitter to be hidden under the trees.

A lot of ex-PMR equipment has a closed control loop to reduce the
RF output to what the communication plan allows for (so PMR folk
can use the same kit for customers who need 0.3 watts or customers
who need 25 watts; all that's needed is a twist of the pot inside).

This circuit makes AM easy: just inject your audio in this control
circuit and with some luck you get reasonably-quality AM.
It won't be hi-fi but superreg receivers never notice;
similary there may be some FM but again superregs never notice
(and it's a nice way to be able to verify a transmitter w/o
the need to carry AM kit!)

Oh, since AM PEP power is 4 times the AM idle power, pls reduce
the idle output power to at most 25% of the max, or things will clip.

Ex-PMR equipment in many places is dime-a-dozen and this gives one
an easy way to build a transmitter for some RDF bootstrap activity,
or during a JOTA or thereabouts.

[I have one transmitter where I can fluently adjust the power from
50mW to 10W PEP, to adjust for the distance and the difficulty
of the RDF. This means that one can make a small hunt for the
young scouts and a larger hunt, with longer distances,
for the older folk, all with the same equipment.
Just a point for inspiration].

Hope this helps,

Geert Jan PE1HZG