Boombox failure on battery power

I am looking at two similar old boomboxes with the same problem: they work fine on line power but stop working when I pull the plug out of the wall. Can anyone tell me what kind of device they use to automatically switch to battery power, and is it a discrete device that I can repair or replace? And am I asking this question in the correct forum, or is there one oriented to this kind of issue?

by SteveWise
April 23, 2019

you may need to pull off the power line from boomboxes.

by wangwg88
April 23, 2019

my old boombox had a simple switch within power cord receptacle that opened the circuit connecting the batteries

by DeanKennedy
May 08, 2019

Thank you, I discovered that one of the boomboxes has such a switch, and when I jiggled it it made contact and the boombox started working on the batteries. Unfortunately, the other one doesn't have such a switch. It apparently uses a relay or circuit activated by the line voltage.

by SteveWise
May 08, 2019

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