A downhole telemetry system comprises an optical fiber, a downhole signal generator, a downhole amplifier, and a first downhole laser. The downhole signal generator can be in optical communication with the optical fiber to generate a signal to be transmitted along the optical fiber. The downhole amplifier can be in optical communication with the optical fiber to receive the signal from the downhole signal generator. The first downhole laser can be in optical communication with the downhole amplifier to generate a first laser light output to power the downhole amplifier. Additional apparatus, methods, and systems are disclosed.