Loose Av-Tv dial on canon a1

I was replacing the battery door on my A1 according to the You tube instructions in "Fix an Old Camera" series. I got the door on but when I went to test the camera if would not fire. Meanwhile I noticed that the Av-tv dial is loose. I can't move to Av successfully. I suspect that it is the source of the problem, namely a mechanical error. Has anyone any experience in re-installing the Av-Tv dial?

Thanks for any help!

You may have missed matching the pin at the bottom side of the AE mode selector with the slot in the actual AE mode switch during reassembly.

 

Remove the release button and AE mode selector again. Try moving the switch (shifts left/right) with a small screwdriver or a pair of tweezers and check if the camera fires again. Switch to AV mode and reinstall the AE mode selector in AV position.

 

Dirk

My deepest apologies Dirk. I never received a notice that anyone had replied to my query. I had left the camera in its plight until today, and then I had the bright idea to search again on the web -- having forgotten that I had written to the forum! Will do as you have written. Thanks again for replying!

Hi Dirk,

I'm hoping you are till reading this post. I think I did what you wrote. I found the switch: it has two prongs as in a "u" and pushing it moved the AT display. I even got it to move with the AT selector. However, it then sticks. So I have a few questions:

1. The AE mode selector has three small protrusions evenly spaced. Am I correct to think that the middle one must fall between the two prongs?

2. The switch [two prongs] are at the base of the "well". Should they be higher, that is, did I somehow push it down?

 

 

Half step forward and one step backwards: Well, I went back to my A1 which has been sitting on my desk for a year --the battery door replaced but the AT-AV dial not connected. I found the slot and got the notch closest to the white marker to slip between, and I can now turn the dial. I also have a black washer below the dial, which I think was there originally. However, if I turn to TV fully the AV-TV selector slips out of position. I don't know how to adjust this other than not to turn the dial fully. The other catch is that the camera now does not work!

I also have a black washer below the dial, which I think was there originally. However, if I turn to TV fully the AV-TV selector slips out of position. I don't know how to adjust this other than not to turn the dial fully.

 

Correct, the washer goes right under the dial. There is another smaller (but optional) washer that goes between the AV/TV dial and the release button. Apart from the thickness of these washers (3 different sizes were available) there is no adjustment. From the picture it looks like the camera has seen quite some use. The dial or switch mechanics may be worn and one or both may have to be replaced.

 

To give you an idea how the actual AE mode switch assembly looks like (the actual electric switch being a wiper that in AV mode connects the two gold-plated contacts barely visible at the bottom left corner of the PCB):

 

 

The other catch is that the camera now does not work!

 

Can you be more specific on this? Not firing as after replacing the battery door or entirely dead now?

I left a reply but it obviously didn't take. After I replaced the battery door I couldn't fire the camera but I could test the battery by depressing the tester. I tried removing and adjusting the two prongs several times and at some time the camera stopped working. Battery is not dead. Also, I could feel the prong catch as I moved it to the right but when I tried to move it back it seemed to have slipped out. It never stayed in position.

I left a reply but it obviously didn't take. After I replaced the battery door I couldn't fire the camera but I could test the battery by depressing the tester. I tried removing and adjusting the two prongs several times and at some time the camera stopped working. Battery is not dead. Also, I could feel the prong catch as I moved it to the right but when I tried to move it back it seemed to have slipped out. It never stayed in position.

I left a reply but it obviously didn't take. After I replaced the battery door I couldn't fire the camera but I could test the battery by depressing the tester. I tried removing and adjusting the two prongs several times and at some time the camera stopped working. Battery is not dead. Also, I could feel the prong catch as I moved it to the right but when I tried to move it back it seemed to have slipped out. It never stayed in position.

Correct, the washer goes right under the dial. There is another smaller (but optional) washer that goes between the AV/TV dial and the release button. Apart from the thickness of these washers (3 different sizes were available) there is no adjustment. From the picture it looks like the camera has seen quite some use. The dial or switch mechanics may be worn and one or both may have to be replaced.

 

To give you an idea how the actual AE mode switch assembly looks like (the actual electric switch being a wiper that in AV mode connects the two gold-plated contacts barely visible at the bottom left corner of the PCB):

 

[ATTACH]1313456[/ATTACH]

 

 

 

Can you be more specific on this? Not firing as after replacing the battery door or entirely dead now?

I am having trouble using this forum! I replied several weeks ago but obviously it didn't take. What I stated was that I removed the top of the A1 again and looked for the switch, which I think I saw. but I don't see how it could touch the two terminals. The switch was pointing at eleven o'clock and the terminals at 7 -- if I am looking at the correct parts. The switch was abutting a screw I think [or pillar/post.] I tried gently to move it but I could not and did not want to force it.

/home/reynold/Desktop/A1%20-%20REPLACE%20BATTERY%20DOOR/SWITCH%20AF-TM/SWITCH_0006.JPG

I have marked the part which is moved by turning the AV/TV dial in the picture. TV mode position in this picture. AV mode position in the picture I posted above (Oct 8).

 

Try moving that part left/right. And check the pin at the bottom side of the AV/TV dial ring for wear.

 

Thanks cmuseuem. I've made a copy and will study your last two letters. I may have bit off more than I can chew. The camera was a functional one but obviously not in best condition. If I can't put it back into working order it will become my study model -- acquiring more of those!

Thanks cmuseum, I followed your advice and jigged the prong left and right and saw the selection change. The movement was a bit sticky at first but I kept working it so moving to the left is fine. At first I thought moving to the right was difficult but I don't think so once I had jigged it a few times. At the end of its travel to the right it seems to "drop" I'm assuming into a catch.

 

I checked the bottom side of the AvTv dial -- there are three "posts"; I presume the one nearest the white mark on the top of the dial is the relevant post. Yes, mine has seen better days to judge from the appearance --it was a replacement I bought on Ebay after destroying the original in my attempt to get it off--but I think it should still work. I can look for another on Ebay but there is never any guarantee that what i buy will be any better. Unless there is a third -party product.

In the future, there is no need to go through all of that for the door.

Get a pair of needle nose, and grab the long hinge pin VERY Tightly, and pull it out.

Remove the Old/Broken door, insert new door, and Slide/Shove that long hinge pin back in.

Thank you denny_rane. I will definitely try your method the next time!

I examined the connection between the pin and the two arms, and contact is only at the top15%. So it's not deeply embedded in the channel between the two arms. Is this normal? I've colored the tips where contact is made. Could this be the cause of the pin slipping out?

The pin indeed looks a bit worn. This is a close-up of a used but good one:

 

 

The pin height should be 0.8mm.

 

I examined the connection between the pin and the two arms, and contact is only at the top15%. So it's not deeply embedded in the channel between the two arms. Is this normal?[ATTACH=full]1334992[/ATTACH]

 

When the ring rotates the pin needs some room to move down the notch. So for the two extreme positions I wouldn't be worried about this position.

Thank you; I'm afraid you might be right. The height seems OK, although I would never swear by my measurement -- had to use a toothpick to get the height and then took the measurement with calipers and also by placing alongside a ruler. Caliper said 0.89 and against the ruler it looks close to approximating 0.8 of a mm. However when I checked the pin it is silvered and worn. So much for buying on EBay. I could cannibalise a non-functioning A1 but I prefer not to. Can one find third-party new parts as one can for the battery door?

I received a new dial, ironically from the same seller [didn't realise it when I bought it]. I have since tried both without success. As a test I would install the dial but I could not move the pin. In fact the older one moves the pin slightly, Something is holding it back. I don't want to try too hard lest I chip it. Perhaps it's not seated properly? It's just the dial with no washers, no release button, but it should work, shouldn't it? The selector moves easily when I push with a wooden stick.