Leica M6 "Classic" Main Circuit Board Replacement Update 2022

[Miles.]

I peruse Don's site (DAG Camera Repair) from time to time as there's fun nuggets of information and today I saw this update from Don:

"As of March, 2022 Leica no longer has main circuit boards for the M6 Classic, about 2 years ago they ran out of M6-TTL main boards. Not good. The M6 circuit boards in photos are replaced damaged boards."

The M6 is almost 40 years old, so I'm certainly not complaining, but it is sad anytime repair gets a little more difficult.

 

[CameraQuest]

So with the dead circuit board the M6 Classic will essentially become a factory converted M4-P. 😕

How will the M6 TTL function with a dead circuit board board?
No meter of course, but will the backward turning shutter dial still function?
Flash sync?

Who has been in that situation an can talk with experience?

 

[raydm6]

I'm thinking if my meter board ever fails in my M6 Classic, I can use the small battery compartment to store something 🙂

More seriously, M6's are fetching top-dollar these days: $3K+. Wonder with an inoperative/irreparable meter how this could affect prices if any.

 

[punkzter]

I'm certainly not excited by this news. It was my understanding that parts from the MP could be used to repair the M6 Classic. I could swear I saw that on this site.

 

[Retro-Grouch]

I'm certainly not excited by this news. It was my understanding that parts from the MP could be used to repair the M6 Classic. I could swear I saw that on this site.

This would seem to make sense as far as the "guts" are concerned, but the electronics may be different. Does the MP have the same finder readout (i.e. same number and configuration of diodes) as the M6? If so, it would have made sense (ha ha!) for Leica to have maintained the same circuit boards. Let's hope.
Just another instance of things getting incrementally more difficult for us film shooters. For me, it's not a question of giving up on film, but rather sucking it up and finding alternatives. Sometimes, though, it does seem to be a hopelessly uphill battle. I got an email yesterday from my favorite lab that they will be discontinuing their services; just another example!

 

[punkzter]

The MP does have a center LED. So it would take someone with far more knowledge than me about repairing M6s and MPs to discuss what it would take to make this swap. But I had thought it was something that could be done.

However, DAG's posting, and his lack of assurance that the circuitry could be upgraded, does make me wonder if it's possible.

 

[Miles.]

The MP does have a center LED. So it would take someone with far more knowledge than me about repairing M6s and MPs to discuss what it would take to make this swap. But I had thought it was something that could be done.

However, DAG's posting, and his lack of assurance that the circuitry could be upgraded, does make me wonder if it's possible.

The backwards compatibility of the MP parts was something I've read about in the past, too, but never from someone I knew personally or a repair tech I've worked with. Don seems to suggest the worst, unfortunately.

 

[Bill Blackwell]

So with the dead circuit board the M6 Classic will essentially become a[n] ... M4-P? ...

Yes.

... How will the M6 TTL function with a dead circuit board?
No meter of course, but will the backward turning shutter dial still function?
Flash sync? ...

The M6TTL will work, but with no meter and the shoe will be "cold" (flash features will not function).

The same thing will happen on each if you remove the battery.

 

[Bill Blackwell]

I'm certainly not excited by this news. It was my understanding that parts from the MP could be used to repair the M6 Classic. I could swear I saw that on this site.

The "guts" of an MP are identical to those of an M6 - but the circuit board is different. This means none of the parts related to flash and meter functions are interchangeable.

 

[nikon_sam]

Just a curious question here...Can the circuit boards be repaired ?
I work on printing presses and sometimes boards go bad and no one's making them anymore.
I've used these guys and they are pretty good at what they do...maybe someone could inquire of their services.

https://www.radwell.com/en-US/

 

[santino]

Don‘t you think a skilled repair man could fix such a board? Are there any micro chips? It should be just a straight forward light meter, something SLRs had many years before the M6 (the TTL is a different story off course).
I even think our chinese friends could manufucture such a board and make our M6s future proof.

 

[Benjamin Marks]

LOL. Just get a used Gossen LunaPro SBC and stop worrying about it. Incident metering works really well and might actually be better than the reflected meter in the camera to begin with.

 

[Chriscrawfordphoto]

LOL. Just get a used Gossen LunaPro SBC and stop worrying about it. Incident metering works really well and might actually be better than the reflected meter in the camera to begin with.

True, but given the insane prices people are demanding for M6 bodies now, I think its reasonable to want them to be repairable.

 

[farlymac]

I'm happy with my M4-P and MC meter II.

PF

 

[Noserider]

Well I would thunk that say 5,000 circuit boards would supply the repair needs of the 150,000 M6 made. 10,000 circuit boards and there might be a nice incentive.

 

[raydm6]

I've worked with EE's (Electrical Engineers) that layed-out very sophisticated (multi-layer: e.g., 14-18 layer) circuit boards (motherboards, daughterboards, backplanes).

I wish I could see the inside of an M6 Classic (not mine 🙂) to see how sophisticated a layout the PCBA(s) are. I did a search on M6 schematic and nothing came up.

Here is a pic from Gus Lazzari of how sophisticated the electronic terrain of a M6 TTL is. Very surprised to see silicone chips in there. They are utilizing SMT (surface mount technology) for the most part. The Flexible (vs. rigid) PCB portions could also be potential points of failure.

Seems there's so much that can go wrong when dis-assembling/re-assembling electronic M's. No wonder most techs don't want to deal with them especially now that these boards will be no longer available.

Link to post: https://www.photo.net/discuss/threads/help-m6ttl-and-problem-with-exposure-dot-and-arrows.430897/




A cut-out image from ThingsCutInHalfPorn - Reddit:



A thread discussing re-wiring the PCBA inside an M6 with images: https://metaldetectingforum.com/showthread.php?t=287805

And an M6A Prototype with top cover off showing electronics (authenticity questionable): https://www.mir.com.my/rb/photograph...2002/index.htm

 

[jordan.dickinson]

I think I might have initiated this DAG update on his site! I recently (about 2 months back) sent in my M6 classic for this very repair and asked him about replacing all circuit boards for a faulty meter as well as just to future proof this old classic. I did ask him specifically about replacing both boards. He ended up repairing the meter board, but as I understand it there is a separate main circuit board, which, as noted, may no longer be available. That said, I got my M6 back from Don and it's in great shape again.

 

[JeffS7444]

I think in many cases, refurbishing the part would be possible, but it would be super helpful to have technical data from Leica including circuit schematics, parts layout diagrams, and some sort of test jig in which the circuit could be tested outside of the camera body itself.

Assuming that we're not dealing with failed obsolete ICs custom-programmed by Leica, perhaps I'd perform a visual inspection, and try reflowing the soldered connections.

 

[Retro-Grouch]

LOL. Just get a used Gossen LunaPro SBC and stop worrying about it. Incident metering works really well and might actually be better than the reflected meter in the camera to begin with.

So true! Both my M6 and M6TTL have working meters, but most of the time I use a small incident hand meter. That process does not slow me down; in fact, I can unobtrusively take a quick reading with the meter at waist level, then slip it back into its belt pouch. I set the camera, zone focus, and have the camera up to my eye and back down before anyone even notices (usually!). The less time you spend with the camera at eye level, metering and focusing, the more unobtrusive you'll be.

 

[raydm6]

LOL. Just get a used Gossen LunaPro SBC and stop worrying about it. Incident metering works really well and might actually be better than the reflected meter in the camera to begin with.

I agree also especially with incident metering. I have an SBC purchased new when I got my AA “The Negative” book back in the 80’s. Pics in that book and “The Print” can give you serious equipment gas.