From Newsgroup: sci.electronics.repair

IIRC, EPROMs (i.e. the chips that can be erased with UV light) don't require battery backup. RAM will, though.
Why weren't EEPROMs or flash memory used? They would have been available when the things were designed (in the 1990s/early 2000s)...
Recently, I picked up one of these radios (GPR4401A) fairly cheaply at a radio rally. A fellow enthusiast in the vicinity remembered using them when working for Motorola, and told me that it was well worth what I paid for it.
We discovered that there was still charge in the battery - noise poured from the speaker when the set was switched, on indicating that - at the very least - the demodulator, amp and transducer were functioning. He told me that the charger was connected via the 15-pin D-Sub connector. An odd choice, given that the connector was designed for signals rather than power! Pinouts and charger details would be most welcome (I don't have a manual, and the Wayback Machine gives me the impression that Chase never got round to setting up a website!)
The most significant problem, though, is a blank LCD - somewhat inconvenient, as the radio is menu-driven. I gather this wasn't an uncommon issue. Any ideas here, as to a fix? The unavailability of schematics (I doubt they didn't exist, at least internally, for such a complex product) or a service manual didn't help.
As regards the possibility of corrupted memory, might it be possible to read the data from the chip (if it's in a set that still works) and stored as a 'backup file'?
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