There have been posts from people searching for the old CP290. I recently received two in trade for one of my products.
One was working but the other was not. The problem was traced to a defective electrolytic capacitor in the power supply. To hopefully give these units a long remaining service life, I replaced the three power supply electrolytics in both units.
Except for a few switches that may need to be pressed a little harder than others, both units now appear to work fine. These units are now available for sale, and you can contact me privately if you need one.
(Sorry, the units have been sold. eBay is probably the best source if you need one.)
Jeff