There are two viewfinders for the camera: The WV-VF02 1 inch CRT eyepiece style of viewfinder, and the WV-VF65 5 inch CRT small screen viewfinder.
The smaller style of viewfinder is really only useful for on-the-shoulder filming. As soon as you put a camera onto a tripod, it becomes awkward to use them, for various reasons: The height of your shot may make it hard to get your eye up to the eyepiece, panning and tilting shots may move the eyepiece out of reach, or you may have to awkwardly step around the tripod legs to keep your eye at the eyepiece, and it may be impossible to look through the eyepiece while doing a tracking shot. As well as other problems, such as trying to look through glasses, wanting to use your other eye by the eyepiece doesn't reach that far, stumbling over things because you can only see through the viewfinder, the resolution may be poor, and the eyepiece lens may not offer enough magnification.
The larger style of viewfinder is used in studios, and for some outdoor work (though often needs a larger shade hood, or something behind the cameraman to block strong light from reflecting off the screen). It allows you to monitor your picture while standing back from the camera.
Common to both types of viewfinder are a few features, such as being able to turn on detail enhancement to aid in focussing, a tally light to show when you're on, and the ability to view an external video source to align your shot with other pictures.
Unfortunately, many CRT display devices produce a horrible squealing sound related to the horizontal output. This can be due to a faulty component (e.g. a failing EHT transformer), or a sympathetic mechanical vibration.
I've come across two WV-VF65 viewfinders that would make horrible noises from time to time, and be silent, otherwise. In their case, it was some tiny ceramic spacers on the legs of two large green resistors in the horizontal output stage, just behind the width-adjust coil, that were picking up almost inaudible mechanical vibrations, and buzzing along with them, depending on the position that they fell into (they're loose on the resistor legs). Squirting a bit of glue onto them shut them up.
To find the culprit, you can very carefully, and very gently, poke at various components with a non-conductive tool, to see if you can make a squeal come and go. Another approach is to make a stethoscope out of some plastic tubing, insert one end in your ear, and slowly move the other end around the board, until you find the point where the squeal is coming from.
NB: There are dangerous voltages inside a video monitor, and people unfamiliar with this should not poke around inside them. Even when turned off and unplugged, high voltages can be stored in various components for a very long time.
The front tally has a delayed response, which throws the timing off for any talent looking at the tally lights. This can be improved by reducing the value of C11 on the board immediately behind the front tally lamp. Changing the original 10µF to be 2µF, worked well for us. It sped up the response, without disrupting the rest of the viewfinder, too much (the display will dim and shrink if the power supply is too low—you want a good power supply that takes cable losses into account, and provides 12 volts at the camera).
The rear tally light is rather poor. It's small, it's very dim, and it's badly placed (it disappears into your blind spot, and the viewfinder hood covers it when panning and tilting). We fitted a second red LED and resistor in parallel with the original ones, so they both light together, and mounted it in the plastic bezel below the picture tube. It's easier to see in that location, and having two lights illuminate makes it more likely for the cameraman to notice at least one of them. Careful disassembly of the plastic bezel is required, as the picture tube is mounted to it, and you don't want to break the neck of the tube during handling.