Assistance with EasyEDA PC Board software and JLPCB: finding stocked resistors for 5.4V Mercury Battery Replacement

[ic-racer]

You need to remove the brass piece at the center. Safety pliers would be a choice, but lens spanner could also be used. That's what these 4 holes are there for.

Are you sure about that?
The two vertical holes in the brass piece are for the screws that hold the ASA disk.
The two horizontal holes have screws coming in from the back, apparently to keep the brass disk (and attached ASA disk) from rotating.
Also the chrome trim disk in the center has a locking screw that also comes in from the back side ( which I may have ruined, trying to remove it.)

 

[ic-racer]

I may have to re-think the voltage regulator as it needs to be used on a device with a negative ground. The Horseman Exposure meter has a positive ground. That means, the voltage regulator would need to be inserted between the battery and the end cap.

 

[Anon Ymous]

Are you sure about that?
The two vertical holes in the brass piece are for the screws that hold the ASA disk.
The two horizontal holes have screws coming in from the back, apparently to keep the brass disk (and attached ASA disk) from rotating.
Also the chrome trim disk in the center has a locking screw that also comes in from the back side ( which I may have ruined, trying to remove it.)

Hmmm, perhaps you're right. The Lunasix has a similar mechanism and two holes that are used to disassemble the knob mechanism, so that's why I proposed rotating the brass piece. Perhaps you could try anyway, provided that you don't ruin any threads.

 

[ic-racer]

I have opened the exposure meter. There are 3 screws holding the chrome lid as circled below. I was wrong, the knob did not need to be removed.

 

[ic-racer]

Zinc cells seem to be the answere here, instead of a voltage regulator and a single battery.

 

[ic-racer]

Evertything back together ready to use.