Generally, if the power received by our detectors isn’t so high that it saturates the receiver channel electronics, our instruments will work with other light sources in the test network. We typically need the received power to be less than the instrument’s output power. If for example the instrument outputs 3 mW, we build the detector electronics to be capable of measuring a 100% reflector so up to 3 mW coming back in would be OK.
If the power of the customer’s transmitter is in excess of a few mW but is at a different wavelength, then using a wavelength selective filter might be helpful. For example, the 6225 operates in the C band, and if the customer’s transmitter operates in the O band, they could use a WDM splitter that passes C band light be routes O band light away from the instrument.
The 6415 and 6225 both are set up to output 3 mW at the front panel. The OBR 4600 will be a little more variable, in the 2-3 mW range. The OVA 5100 will be closer to 1.5 mW out. Unless there is an amplifier in the customer’s network, we don’t expect the power to be high enough to damage the customer’s receivers.