OTDR is a complex Testing Instrument on fiber cable tesing. And prices are much difference. When you select an OTDR, you should know the parameters listed as below,
1) Wavelength
> Single mode 1310nm
> Single model 1550nm
> Single mode 1310nm and 1550nm
> PON OTDR (with filter for active fiber testing) 1625nm/1550nm
> Multi mode 850nm 1300nm
> Sing mode and Multi mode 850nm 1300nm 1310nm 1550nm
2) Dynamic range
From 22dB to 45dB. The higher, the better for longer fiber testing. Generally, handheld OTDRs are higher than 45dB.
3) Pulse width range
The large pulse width takes more energy to see far distance, but resolution is low.
4) Testing Distance
5) Report print
by PC software or report created in OTDR directly
6) Other functions
VFL, OPM, OLS, Event Map, etc
