It used to be that an OSD was more trouble than it was worth. Not anymore! Modern OSDs are easy to install, reliable, and offer as much (or as little) functionality as you want.
Here are four different ways to put an OSD onto your quadcopter.
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https://goo.gl/s0sW4v
The Holybro PDBOSD v1.2 follows the familiar model of the RROSD and the HubOSD. The OSD is integrated into the PDB, and since you were going to install a PDB anyway, there's no additional work to include the PDB. Unlike the RROSD, the Holybro PDBOSD v1.2 uses MWOSD so it integrates with your flight controller to let you change PIDs and so forth in the field.
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https://goo.gl/ETJG5F
The Furious FPV Passado combines an OSD and video transmitter (vTX) into a 36mm stackable board. One feature that makes it stand out is that it can be turned on and off via an Aux channel, to avoid stomping on other people at the flight field by accident.
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The DMT video transmitter from UBAD puts the OSD into the vTX! This product is not released yet at the time of making this video.
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https://goo.gl/EflWJ6
The RROSD v2 is the evolution of the original PDB+OSD board. Unlike the Holybro PDBOSD, this one is completely self-contained. It doesn't integrate with the FC, so there's no configuration or calibration or UARTs or etc. Just solder it up and go. The RROSD v2 has an improved pad layout and better voltage regulators than the v1, as well as a much higher current rating.
