Leica R3 MOT ELECTRONIC: Heading into the unknown

[Andreas Thaler]

Our colleague @miha asked me if I would like to look at his R3 MOT. There is a problem with a jumping needle in the viewfinder. Maybe also the aperture priority mode is concerned.

I was hesitant about whether I wanted to do this. Because I didn't have a Leica R on the table yet. And although there are many reports on the web about problems with its electronics, there are hardly any instructions on how to solve them. I also couldn't find the service manual for the R3. So a departure into the unknown that challenges me.

The Minolta XE (XE-1, XE-7) is related to the R3. There is more information about this camera. For example, that cleaning the contacts can help. Because, as I read on the web, many R3s sat in the display case and were not used for many years. This shouldn't bother the electronics. Except for electrolytic capacitors, which age and can expire. And contacts that can oxidize and then no longer conduct or only conduct unreliably. This is where I will start.


The first step will be …

… to remove the base plate and top case cover and inspect the electronics underneath for any abnormalities. Wherever I can clean something or soldering joints no longer look good, I will try to improve. If electrolytic capacitors or tantalum capacitors are installed, I can check whether they are working.

Of course I won't try this on the R3 MOT from Miha, but on an R3 ELECTRONIC from my inventory, which is also said to have problems with the electronics. A second problem concerns the tensioning lever, which sometimes does not engage.

I only bought it yesterday and haven't tried it out yet. I assume that the two models are constructed more or less the same.

Of course, this project requires some courage, because I consider the chances of success to be slim, why should I succeed in something that others couldn't. But we'll see, anyway it will definitely be an interesting journey into the unknown

I'll keep you updated on the progress.

 

[BMbikerider]

You could do worse than try to find a repair manual for a Minolta XE1 which was a direct forebear to the R3. The electronics as far as I am aware are very similar because the R3 was based upon the Minolta version. There were changes to the R3 such as the addition of a spot meter and the mirror box and body were 'beefed' up to improve the design but again as far as I am aware the shutter and metering system (apart from the spot variation are more or less the same.)

I can put you im touch with a repair engineer based in UK (now semi retired) who worked on Minolta models in the past but is now self employed on a part time basis who may be able to point you in the right direction.

The E mail attached to his website is dave@camerarepairworkshop.co.uk

 

[Andreas Thaler]

I can put you im touch with a repair engineer based in UK (now semi retired) who worked on Minolta models in the past but is now self employed on a part time basis who may be able to point you in the right direction.

The E mail attached to his website is dave@camerarepairworkshop.co.uk

Thanks, that's very nice, but I try to do my own repairs

I once had an R7 serviced in Europe. I paid about 650 USD for it. I'll never do that again.

 

[Andreas Thaler]

Now I'm wondering whether I should use my JIS or Phillips screwdrivers for Leica. JIS should fit both screw head profiles. So it starts with the decisions

 

[BMbikerider]

Thanks, that's very nice, but I try to do my own repairs

I once had an R7 serviced in Europe. I paid about 650 USD for it. I'll never do that again.

I was not suggesting you send the camera(s) to him but to e mail him and ask his advice because you seem to be lacking technical information. He has always been very obliging when I have 'phoned up for information . I have used him in the past to sort out a well worn Minolta XM and he did a cracking job. I also understand (not confirmed) that when Minolta went out of business he bought up a lot of their spares which if true could be relevant and helpful to your task in hand.

 

[Andreas Thaler]

… you seem to be lacking technical information.

Yes that is correct. That's why I'm currently setting up my little workshop in the kitchen and getting started

 

[Andreas Thaler]

As far as I know, the Minolta XE has cables running for signal transmission. This is tricky, so I'll watch this video first. And I hope that I can make progress with my R3 too.

 

[Andreas Thaler]

OFF Topic

@BMbikerider

I appreciate your friendly and well-intentioned advice and would like to thank you again for it

Just to avoid being misunderstood we recently had this topic in my F4 project.

I am always happy to receive professional advice. But it is important to me to make progress myself and to use publicly available sources or books, service documents, advice by colleagues here etc.

Under no circumstances will I ask a professional for tips that I then publish here. That wouldn't be okay with me, that's his know-how and capital. If he's kind enough to do that and be okay with it, that's his decision. But I don't want that. My father was a craftsman and artist and was very helpful when others asked him for advice, who then became his competitors. I learned from it.

I can decide not to do a repair myself and give the device to a professional. In this case I receive an invoice but no detailed explanation of how the problem was resolved. By doing so, the professional would be harming himself.

As I said, I work for my own pleasure, have no commercial interests and am not dissatisfied with my progress. If I can pass on experiences here - good and bad - for the benefit of others, I'm happy.

Anyway I place valuable or overly complicated pieces in professional hands. I'm not a fool hopefully

OT OVER

 

[mtnbkr]

Now I'm wondering whether I should use my JIS or Phillips screwdrivers for Leica. JIS should fit both screw head profiles. So it starts with the decisions

Get the JIS. I bought a set of JIS screwdrivers to get the smallest one (was cheaper than buying just one). They grip regular Philips screws so well; I use the rest of the set in my shop for general utility.

Sorry, I misread, I thought you were making a purchase decision. Upon rereading, I see you already have them. In that case, I'd use the JIS ones.

Chris

 

[Andreas Thaler]

Get the JIS. I bought a set of JIS screwdrivers to get the smallest one (was cheaper than buying just one). They grip regular Philips screws so well; I use the rest of the set in my shop for general utility.

Sorry, I misread, I thought you were making a purchase decision. Upon rereading, I see you already have them. In that case, I'd use the JIS ones.

Chris

Thanks, Chris!

It's not always easy with the screws

 

[miha]

This is getting exciting @Andreas Thaler ! So you purchased an R3 just to practice on it before you perform the surgery on mine?

 

[Andreas Thaler]

This is getting exciting @Andreas Thaler ! So you purchased an R3 just to practice on it before you perform the surgery on mine?

Let's put it this way - I accidentally found yesterday one in my box that I had already forgotten

 

[Andreas Thaler]

No, I'm interested and inspired by your R3 MOT, so I bought some copies very cheaply.

From the R3 I would like to make the jump to the Minolta XE-1, which has always fascinated me from a technical point of view.

 

[miha]

Well, what can I say, very kind of you Andreas. I will follow this thread with great interest... whatever the outcome may be.

 

[Andreas Thaler]

I will follow this thread with great interest... whatever the outcome may be.

Me too

 

[Andreas Thaler]

This will continue soon, unfortunately I'm not quite fit at the moment, but that's probably stage fright

 

[Andreas Thaler]

Time to move on from here!

Since the R3 is closely related to the Minolta XE/XE-1/XE-7, these two videos could help:





I'll start with the first video in the hope that the conditions are similar to the R3. If I'm lucky, this might solve the problem. If not, continue with the second video.

It is interesting that there are no service documents for Leica R on the web. Presumably still kept under wraps as a trade secret.

 

[Andreas Thaler]

Boarding completed, we depart tomorrow (CET)

 

[Laurent]

Good, I'm impatient!

 

[beemermark]

The Minolta XE (XE-1, XE-7) is related to the R3.

I wonder where the internet fact started that the Minolta XE's and the Leica R3 are the same or even related. The R3 is a rat nest of wires. One board on each side of the prism, you can't remove and repair one without a wire breaking when you try to reassemble. The XE line wiring is very clean and easy to work on. Maybe they have the same body casting and maybe even the same shutter. If anyone wants practice on either model I have two R3's and two XE-7's. Reason no competent repair person will work on an R3 but will work on an XE

 

[Andreas Thaler]

I wonder where the internet fact started that the Minolta XE's and the Leica R3 are the same or even related. The R3 is a rat nest of wires. One board on each side of the prism, you can't remove and repair one without a wire breaking when you try to reassemble. The XE line wiring is very clean and easy to work on. Maybe they have the same body casting and maybe even the same shutter. If anyone wants practice on either model I have two R3's and two XE-7's. Reason no competent repair person will work on an R3 but will work on an XE

Thanks for the warning!

I have both models here and hope to be able to draw conclusions from the XE-1 about the R3. I don't have any other help.

Without knowing anything for sure, I suspect contact problems, at least that's what the XE-1 is known for. And here again there should be sophisticated mechanical switches that can be disassembled and cleaned.

The title definitely hits home with Heading into the unknown

 

[Andreas Thaler]

It's actually about an R3 MOT, which I hope is largely identical to the R3 ELECTRONIC.

But first I have to find out if my Leica R lenses fit. I haven't researched it yet, but the bayonet should be compatible with the later R models.

 

[Andreas Thaler]

Here someone created a work of art from a dismantled Leica R3 MOT:

https://www.funbox.design/fr/product-page/dassembled-mechanical-film-camera-leica-r3

 

[Andreas Thaler]

My research into repairs to the R3 didn't produce any useful results. There are many calls for help regarding problems with electronics in the forums, but I haven't found any concrete solutions.

That doesn't matter, we'll take it step by step without any pressure to succeed.

In the few photos of opened R3 I saw a lot of electrical mechanics that could be checked and cleaned.

But first I'll do an error analysis of what doesn't work.

 

[Andreas Thaler]

Leica Camera Repair Handbook: Repairing and Restoring Collectible Leica Cameras by Thomas Tomosy

There is a chapter on the R3.

I can't find a way to purchase the book and would be very interested. Maybe someone would like to make me an offer?