Help with fixing Nikon Lensometer

**snv** · 09-29-2005, 05:39 PM

Hello,

I have a nikon EL-7S lensometer. It worked wonderfully until recently, the light went out. The power light turn on when turned on the switch. It is powered by either battery or AC adapter.

This unit doesn't have bulb. I believed it is LED. Does anyone have a manual or recommended someone that can change or fix the LED?

thanks

**QDO1** · 09-30-2005, 04:23 AM

It is more likley to be the ON switch / pad ... something that would wear out much faster than the LED . If the Lensmeter also runs off a transformer, then there might be a fuse in it somewhere, to protect it from the results of somone attaching the wrong transformer to the lensmeter. I know a few places in the UK that would repair it, but I think you would probrably be ok with any reputable electronics workshop

**PAkev** · 09-30-2005, 11:35 AM

I have the same lensometer and it has worked like a charm from the day I bought it. I inquired about purchasing a spare bulb to have on hand but was advised by the folks at Nikon it indeed does not have a bulb.

Have you tried it on both AC and battery power to see if the problem is consistant with the power source? I've never had mine apart but agree what QD posted. Do you feel a little resistance and hear a click when you push the rocker (on-off) switch or is it loose? If you turn the unit upside down you will see a fuse right under the vent hole. Also if you shine a penlight in you can tell if the fuse is blown or not.

**snv** · 09-30-2005, 02:01 PM

I tried both with AC adapter and Battery. The Power light turns on without any resistance. There's a fuse on the base of the lensometer, but I checked it and the fuse is OK. I even buy a brand new one and install it just to make sure.

One thing is that when the power turned on. I can actually see the reticle, but it is so faint, you have to really pay attention or else you wouldn't notice that it is there. If I tried to measure a lens, there's no way that I can see the reticle anymore.

Any other suggestions?

**QDO1** · 09-30-2005, 02:07 PM

there isnt an obstruction (like stamping prongs) or the index changing flap for example in the way?

**snv** · 09-30-2005, 02:34 PM

There's no obstruction in the way. We used this lensometer for many years. Nothing has been change except for this problem.

**PAkev** · 09-30-2005, 08:38 PM

When you activate (turn on) the rocker switch does the little green light below it go on? If so, It's probably NOT a power problem.

Also take off the little (grey) funnel shaped lens stop and see if the lens underneath it has become loose, opaque with dust, or compromised in any other way.

I will take a look at mine when I go into the lab tomorrow and post any other possibilities I can come up with.

Kevin

**PAkev** · 10-01-2005, 04:15 PM

OK here is a simple diagnostic procedure that will identify if your problem is in the power (bottom) measuring part or the eyepiece (top) which you look through:

First turn the unit on

Then turn the lights off in the room and slip an opaque piece of paper between about 2-3 inches above the lens stop. Look underneath the paper to see if there is a beam of light shining on it. If so, your problem is probably in the eyepiece. The EL-7 has a hollow portiion on the bottom of the eyepiece which could have collected dust or perhaps someone stuck something in there.

Let us know if you find the problem.

Kevin