I've had one that I bought from SJT Enterprises quite a long time ago, It still works fine. The power supply unit looks a lot like the one from MicroMark.
After the novelty wore off, though, I find that I don't use it very often. For that reason, you might want to reconsider the power supply unit. You may find that a battery is really adequate for your needs, especially if you're mounting it on a flat car so it's easy to get to. (Mine is inside a subway car, so changing batteries would have been an annoying task.)
For most of these, there is a problem with reception of the camera signal by the receiver box. There are a lot of "dropouts" which cause the picture to momentarily break up. Some people blame this on poor power pickup, but I tried running with a battery and found the results were just about the same. On the other hand, the subway car came from the factory with interior lights, so it has good 8-wheel power pickup that I was able to piggy-back off of. If you add wipers to standard freight car trucks, you might have trouble getting reliable pickup.
The best installation I've ever seen of one of these had a ceiling-mounted antenna from Radio Shack. It was a better antenna than the one provided, and gave a good clean signal. Of course, being above the layout meant a direct path to the transmitter not obstructed by layout items, other trains or people.
It takes an iron man to play with a toy iron horse.
I've been using the Micromark camera for about seven years now with no problems.
The antenna is bendable, and I have bent it down some since these pics were taken.
Kevin
http://chatanuga.org/RailPage.html
http://chatanuga.org/WLMR.html
I see several thread on filming layout and cameras, but it is always good to ask again as new products may be available.
I am thinking of getting something like the video camera offered by Micro Mark with the power from the rails adapter etc.
Any recent advice on this or a better product for adding a video camera to the layout?
Any non-rr hobby products (surveillance/spy shop -type stuff) that are better that you have adapted or seen adapted to someone's layout?
Thanks for any tips.