bc560xlt not storing channels

[riccityracc]

Hi i have an old uniden bearcat bc560xlt that i picked up from rarsfest for a dollar and the radio itself works after swapping the antenna connector from din to so239 and attaching an external speaker but once i program in channels after a few minutes all the channels are programmed to 00.000 again, read in the manual it has a feature that stores the memory for 60 days with a capacitor, wondering if its just a quick fix because id like to put this scanner in my car since its small and has enough channels for all the local emergency and some ham frequencies.

 

[tvengr]

Are the frequencies lost while still turned on and corrected to power?

 

[riccityracc]

Are the frequencies lost while still turned on and corrected to power?

yes once i have the channels programmed i can scan them and they worked for a few minutes but after maybe 10 minutes of scanning and not turning off the scanner the channels were blank, the only thing i could think it may be with the power is i am using a power supply to a radio shack pro 2050 because its the only power supply with the barrel connector that fits it that i have around

 

[pro92b]

The AC adapter from the PRO-2050 should power the BC560XLT without issue.

Memory retention in the BC560XLT is supported by a capacitor, C35, 3300uF 6.3V. If you do not interrupt the power source for the radio, C35 has no work to do and it should not cause programming loss. Regardless, after all the years since the radio was produced, it is worthwhile to replace C35.

I have seen a note on the web that capacitor C209 in the CPU reset circuit can go bad and cause memory issues. This is a 0.47uF 50V electrolytic capacitor on the CPU board. It may be possible to replace the electrolytic with polyester film for better performance and reliability. It would be necessary to confirm the physical size for fit on the board. Mouser part number 505-MKS2B034701B00JS is a candidate. Otherwise a suitable electrolytic would be Mouser part number 710-860160672001.

The service manual for the BC560XLT can be found on mods.dk if you need it. They also have the service manual for the Realistic PRO-2025 which is identical. Get both manuals since the Realistic manual is generally a better copy that is easier to read.