I have a pair of old powered mixers that partially work.
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The Fender LX-1506 cuts out if the volume is turned up too high, so it needs a powered amplifier on its output (or repairs done; I suspect one of the power transistors is shot).
The Yamaha EM-150 only works on 1 of its outputs and 5 of its inputs, and blows a fuse if you connect the wrong ones. Comes with spare fuses.
Good for spare parts, or you could connect them together for an ad-hoc powered amplifier.