Motorola desk mike - Anyone have schematic?

[Opcom]

I found this nice Motorola desk mike.. Lightning bolt and everything! I know these were for FM base stations, but last time I used a Motorola desk mike, the sound was very good, very clear. That old metal one didn't have a built-in amp or anything so it was simpler to figure out.

Can any Motorola folks help me out on this thing?

Not sure of the model because of the mess on the bottom of it. To me, I see ?MN1008C printed on the steel bottom plate.
But it looks like pictures of the HMN1050D or HMN1088. There is no label that I can see.

The board physical layout looks much like the HMN1050D board shown in the attached diagram (found on qrz), but the traces on mine are thicker and the wire colors are different.

Maybe it's the same, or not.. The power and audio seem to be supplied on the same wire, which means that there is a DC supply in the radio, supplying DC through a resistor or transformer, so as to pick off the audio while supplying power. I would need to know what's in whatever radio it was used with - what the input circuit is. Probably fairly standard I guess.

The big number on the back of the circuit board is TRN4351A. (not shown on the schematic image there).

I figured out how to take it all apart - a nice puzzle with a machined telescoping rod, worthy of Motorola, better than most. 8-)

Just thinking about.. PTT, plus mashing the other button to key the amp, if necessary.

[WU2D]

I can look because I adapted one of those to my Micom about 10 years ago.

[Opcom]

Thank you! I would appreciate it very much to know how you got yours working with the right load and voltage.