Orientek TLS-25M Mini Optical Light Source SM 1310/1550nm

Are you a technician for a certain telephone and telegraph company in America? Are you tired of begging your supervisor for test overrides, or driving all the way to the PFP to get a passing test? Boy, do I have a solution for you! Joking aside (I do not condone falsifying company documents 👀), this device does what it’s supposed to do very well for the price. I got it primarily to generate 2khz tone on a fiber, which I detect with the Orientek TFI-40 wand. Furthest I’ve tested it is 6,000ft, and it works great. If you want something that generates light for legitimate purposes 👀 or something that generates 2khz tone for situations where you can’t use a laser for fiber identification, this is your best bet.

Smooth functionality, accurate, great value, very easy to use, durable

Somebody had to be among the first people to buy this Optical Light Source (OLS) and his companion the Orientek T25M Optical Power Meter (OPM). For the money, I figured I'd give the pair a try. I don't have other optical test equipment to test these against, so this review is really for the pair of these devices. Let me start by saying that I grabbed some random LC/UPC to "2.5mm universal Interface" converters from here on Amazon, and I used those for all my testing. They didn't properly "lock" on to either unit (the OPM has threads for an adapter, the OLS does not). The one-page OLS spec (on the Orientek web site) says the generated power is -5dbm. I plugged a 3m single mode fiber LC to LC fiber into the adapters, turned on the OPM and OLS, set them both to 1550nm, and... behold... a reading that varied from between -4.something to -5.something -- I say ".something" because the value I got bounced around quite a bit. If I unplug the fiber from one end, the reading on the OPM say "LO" -- So, SORT of good... though how we could get -4dbm from a light source that's rated at -5dbm is certainly a good question. But, let's just go with it. Here's where it gets more fun: I changed the OLS from 1550nm to 1310nm. But I left the OPM on 1550nm. I got only a slightly different power reading on the OPM (-5.something dbm). Hmmmm.... Then I switched the OPM to 1625nm. I still got a very similar power reading (again, about -5.something dbm). So, we know that either the OPM isn't very selective or the OLS isn't very specific. I added a modulated signal at the OLS, and the OPM detected the proper modulation each time and indicated a different (sometimes lower, sometimes higher) power level than with no modulation applied. I measured other lengths of SM optical fiber (up to 30m... I don't have anything longer to try) and got pretty much the same readings, which is as it should be given that the insertion loss for the 30m fiber cable I have is spec'ed at <= 0.15dbm (if you can believe the package, but that's a whole other story). Finally, I measured a pair of fibers coupled together with and LC/UPC F to LC/UPC F fiber coupler. I didn't see any insertion loss, which (again) is reasonable given that the couplers are spec'ed at 0.2dB IL. In summary, what can I say about these devices? Well, they're obviously not precision instruments. I'd say they're good enough to detect massive issues (like, "Did I break that fiber or the connector on it?")... They're good enough to allow you to identify individual fibers if you have a bundle. They're good enough for home use (which is why I bought them). I'm going to keep them, but there are lots of little, niggling, issues that result in my not being thrilled with my purchase.

The light works but the battery life is a joke. The product barely has enough power for 1 day of work. So buy plenty of batteries.

Works as advertised

No way to know if this works or. Not as it did not come with charger

USB port broke second time I used it. Will still work with batteries.