Steve Roberts
Member
Hi,
Thanks everyone for the replies and for some interesting and useful links.
The bottom line is that I concluded that the problem was mechanical and with the aperture coupling lever in the DP-1. I disassembled the meter and could see the linkage mechanism end-wise on. I didn't feel confident in dismantling it, but could see that when trying to go into the f5.6 to f16 range a cam was moving as far as the roller on a spring-loaded lever. The lever/roller assembly were reluctant to move, but with a single drop of light machine oil on the roller pivot and another on the pivot of the lever a bit of careful wiggling soon had it all moving freely. I suspect that the problem was caused by the previous lubricant having gone gunky. With a bit of luck it will now work for another 46 years (and see me out!)
I'll clean the electrical contacts whilst it's all in pieces but I'm confident that the original problem has now been resolved.
Thanks again and best wishes,
Steve
Thanks everyone for the replies and for some interesting and useful links.
The bottom line is that I concluded that the problem was mechanical and with the aperture coupling lever in the DP-1. I disassembled the meter and could see the linkage mechanism end-wise on. I didn't feel confident in dismantling it, but could see that when trying to go into the f5.6 to f16 range a cam was moving as far as the roller on a spring-loaded lever. The lever/roller assembly were reluctant to move, but with a single drop of light machine oil on the roller pivot and another on the pivot of the lever a bit of careful wiggling soon had it all moving freely. I suspect that the problem was caused by the previous lubricant having gone gunky. With a bit of luck it will now work for another 46 years (and see me out!)
I'll clean the electrical contacts whilst it's all in pieces but I'm confident that the original problem has now been resolved.
Thanks again and best wishes,
Steve