Fed 3A rangefinder problem

Hello all,

For some reason my Fed 3a has developed a problem in which the rangefinder image is now below the viewfinder image.

Now this wouldn't have surprised me so much but I haven't used it since it came back from being adjusted because it wouldn't focus to infinity, when I got it back I checked and the rangefinder window worked as it should, both with the vertical and horizontal. As far as I'm aware I've not dropped it, banged it against anything nor dropped anything onto it, so does anyone have a clue as to why the rangefinder image would drop below the viewfinder image?

Any help would be much appreciated.

The round front window is a prism
Remove the chrome ring and you will see a anut with two small dents .
Turn it up to alignment and be happy
Regards

Thanks for the info, Luiz. I wasn't sure about trying that as I recently read that when you alter one setting of the rangefinder, you always have to alter the other and I didn't want to make the problem worse in case it made any work more expensive.

The main thing I'm worried about now, is exactly HOW could the rangefinder window image drop below the real image when the camera has just been sat on the shelf with no bangs or bumps? Could there be a more serious problem with whatever holds the rangefinder prisms/mirrors in place?

Someone tried to tight or loose the external round chromed crown.
There are no other possibilities.Camera could be felt down or received a strong shock in this case the internal ball bearing took out of
place.
Regards

Thanks for the reply Luiz. Unfortunately when I got it back from the camera after being adjusted I checked it and it was fine. There are some white framed windows on the houses opposite mine in the square where I live, and they are more than 70 feet away and the rangefinder window and the real image aligned properly when I focused on them when I first checked it.

Now that I come to think about it, a month or two ago I had nothing to do and was idly aiming some of my cameras and focusing them and so on and I noticed that the rangefinder window of the Fed 3A was very slightly below the real image but moved up enough for the horizontal lines to be aligned when I focused the lens on any particular object.

I don't remember dropping it or banging it. Is there nothing that holds the ball bearing in place that could've just "worn out"? If not, then I presume I must have banged it. I'll see what happens when I adjust the height of the rangefinder window. I'll then leave it a few weeks and then check it for alignment. I'll do that over a few months and then decide if it needs a technician to fix it.

SOME YEARS AGO SOMEONE CAME WITH THIS SAME PROBLEM. i EXPLAINED IT WIT PICTURES THAT IS SOME WHERE IN THIS FORUM BUT NOW IT IS IMPOSSIBLE TO FIND. WE HAVE A NEAR 20 YEARS OF POSTS. AND I REGRET MUCH THE CLOSURE OF WIKI TO POST NEW EXPLANATIONS
REGARDS
LP

Luiz, Thank you for the extra info. I'll let you know how I get on with adjusting it AND I will make a note of the date I do it and see if the rangefinder image "drops" compared to the real image to see if there are any changes and if so over what time scale.