Vintage Bogen Challenger CHA-20.It does work with microphone, in fact it was used to call out bingo numbers at the local Grange Hall!Terry Kath of Chicago used a Bogen PA on 25 or 6 to 4.This is a great specimen to morph into a guitar amp for very little money!Features PTP wiring,new JJ Tubes, older Chinese Preamps and vintage rectifier, logo lights up and the funky handle that does come off! I was quoted 200.00 to add input jack and cap job with 1/4” speaker jack that yields a killer tweed amp, but I’ve since changed direction.PM for more info.$300.00