Model rv-b99 loses presets and does not power off

From memory, no pun intended, there is a large value capacitor or a battery type BN-V416 that holds the memory settings.
A service engineer should be able to help.

Don,

That actually makes sense. Mine has been running fine at low power and restarts after really cranking it after a couple of minutes. I will probably go ahead and run a line to the battery as well. Thanks for commenting back, I appreciate it!

need to check the yellow constant power wire on wire harness to see

1. connected to battery with constant 12 volts
2. if wire has power 12 volts

if no power check fuses to see if blown

with out this wire working right you will never have pre set station on radio or clock
with correct time

I found the user manual but they want $4.95
http://www.s100-manuals.com/manualdetails.asp?id=306283

It could be a battery, a bit like the type you get in watches. But I reckon it's a memory retention capacitor that has failed. These are small looking things that look like electrolytic capacitors that have been squashed from above. They appear to have a working voltage of around 5.5 volts too. I am enclosing a picture of one, though it could vary in style. You might find it near the main display of the unit.

You need to take the unit apart. If you pull hard to open the door, you`ll break the plastic connector that moves the head up and down.

tune into the station you want as normal. Then on the remote, press & hold the number key for the preset number you want. This will flash in the display to show you it's set. You can preset 30 FM & 15 AM stations.

Look in the back of the boombox where the large D-cell batteries are. Beneath the large batteries there is a location for smaller AA size batteries. The AA size batteries are used to maintain the radio station pre-sets when the unit is unplugged. Check to see that these batteries are installed or if they need to be replaced with new ones.

if you dont want to buy a new radio install a toggle switch to both of the power wires. you will keep losing your presets btu at least it wont run your battery down.

idk