$50 Grass Valley AVDC-G2
The Grass Valley ADVC G2 HDMI & SDI to Analog & SDI Multi-Functional Converter / Downconverter with Frame Sync is a 1/3 RU box that performs a great many functions for its compact size. The inputs are HDMI and 3G/HD/SD-SDI, plus there's a BNC for a reference signal input. The outputs comprise a full complement of analog connections (including separate audio) and two BNCs that serve as dual 3G/HD/SD-SDI outputs.
In between input and output, the ADVC G2 serves as a downconverter and a frame synchronizer for SDI (via the reference signal input). With a reference signal in, the SDI out can be locked to sync, which is useful for connecting this output to a switcher. The versatile box also de-embeds audio from the HDMI and SDI inputs so that it can be monitored and mixed separately as AES/EBU and/or analog signals.
With analog component, composite, and S-Video outputs, the ADVC G2 can be used as a monitoring device for SDI and HDMI signals. The ADVC G2 can also be used to convert HDMI to 3G/HD/SD-SDI, with support for formats up to and including 1080p60. Offering input & output support for most DTV formats, the hardware could prove useful for converting signals to match your facility's house format.