September 2015: Praktica LLC

First concern on this camera body: the moving up / down of the mirror is extremely lazy, it's impossible to shoot.
I start by disassembling, must take off the leatherette, and remove bottom and top cover to be able to remove the mirror block.

A wire (blue) connects the mirror block to the housing, inaccessible at both ends, it passes behind the self-timer mechanism, I had to remove it to gain a little freedom of movement.
The culprit is not far away, the wheel indicated by an arrow is used to damp the movement of the mirror, its axle is gummed by an old frozen lubricant. After cleaning, the mirror regains functionality.
Reassembling, the shutter operates normally ; let's go to the next problem.

A battery contact is missing, I found it wandering in the shutter. I put it in the compartment for the photo, it is (1). It prolonged originally the lug (2).

This part bears the graphite potentiometer track coupled to the shutter and film speed selector (I made felt markers to find my way in case of dismantling).
I removed the plastic protection and soldered a piece of wire.

Then I put a plastic insulation (shrink sleeve) and soldered the battery contact in place.

Reassembly...

And installation of the battery; curious: no indication of + or - on this battery; but in the other direction the contacts would not do.
The lightmeter works.

The shutter speeds indicative plate and the cover of the cocking lever are glued; not always easy to remove for removing the top cover. The reassembly ends with their repositioning and rebonding of the leatherette.

And the Praktica LLC can go back to it's owner.