04-06-2024, 07:25 AM
i have done an initial inspection. The rectifier PCB and some associated wiring is badly scorched with extensive repair work. The rectifier for the +5V logic supply is odd. There are 3x BY164 bridges in parallel. These are rated at 1.5A (some sources say 1.6A). The manual says the +5V supply is current limited at 1.8A.
This looks like a typically Philips odd design decision. The current sharing will be poor, though by fitting 4.5A total rectifiers for a 1.8A supply this shouldn't matter. I wonder if this was the cause of the original burn up. A scan of a different version of the manual shows they changed their mind and fitted a larger external bridge on the back panel. Our has the three bridges replaced and also has an external bridge.
This looks like a typically Philips odd design decision. The current sharing will be poor, though by fitting 4.5A total rectifiers for a 1.8A supply this shouldn't matter. I wonder if this was the cause of the original burn up. A scan of a different version of the manual shows they changed their mind and fitted a larger external bridge on the back panel. Our has the three bridges replaced and also has an external bridge.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
