Bearcat BC855XLT Loosing Memory

Hi,

I have a Bearcat BC 855XLT scanner (scanning radio) in my service shop. No schematic. The radio lost all it's memory, but I was able to reprogram some of the channels and the radio works.

The OM says, "A unique capacitor type memory back-up eliminates the need for batteries". I suspect that maybe this capacitor is going bad(?), but since I don't have a schematic, I have no idea where this capacitor is located.

Thanks in advance, Brad

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Reply to
Brad
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The is a type of RAM called CapStore. It was a common static RAM, with some flash memory. It detected a power loss and stored the contents in the flash memory, and on power up, wrote it back to the static memory. We used it to replace the 2k * 8 battery backed RAM in our products.

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Reply to
Michael A. Terrell

If not this device, then perhaps you have static RAM with standby power from a supercap (perhaps about 1F). Look for a squat round package which looks a little like an electrolytic or a battery cell encased in plastic. I have a scanner so equipped and have seen supercaps used in many handheld and ruggedized devices where battery (cell) changeout would be difficult.

Michael

Reply to
msg

If it's loose, tighten it.

Reply to
PanHandler

The manual states the memory backup is only good for up to 3 days with no power.

Reply to
Ken Layton

I have an old digital radio tuner with 8 presets. Its memory is kept out of a standard 470uF capacitor, probably very low consumption SRAM and lasts a few weeks.

Reply to
Jeroni Paul

On Mon, 15 Sep 2008 13:08:01 GMT, snipped-for-privacy@verizon.net (Brad) put finger to keyboard and composed:

There are some Uniden Bearcat service manuals here:

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Your model's SM is not listed, but maybe a similar memory backup scheme is used in other models. Be aware that the above site allows only one free download in 4 days.

- Franc Zabkar

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Reply to
Franc Zabkar

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