<p>On the early Nikkormats (FT, FTn, FT2), the resistor under the speed setting ring wears out causing the light meter to be jumpy. I have read that they fixed this problem by using more durable material for the resistor on the FT3 and later FT2s. I have one FT2 with a solid meter but the meter on my FT3 is jumpy so there may be other factors at work as well.<br>
The FT and FTn used a mercury battery for which you can substitute a 675 zinc-air hearing aid battery. Later Nikkormats used a silver oxide battery. </p>