Here is a short video I recorded about the system.
Specifications Power: 6 1,5v batteries (UM2 type), or 9v DC 200mA transformer Games: Cartridges PC-501 to PC-508 Controllers: 2 detachable joysticks without return, and with a push-button for serving. Scoring: On screen Video: UHF Channel 36, SECAM 625-L colour Extension: 5 pins DIN plug on the left side for the gun/rifle
Value: About £15. While being old and not overly common, these are not particularly sought after consoles.