Rowe-Ami MM series amplifiers

General information. The MM3, MM4, MM5, and MM6 jukeboxes had three different amplifiers that could be ordered.

Single 50 watt transistor amplifier with seperate output transformer assembly.

Single 100 watt transistor amplifier with seperate output transformer assembly.

Hybrid sound system with a 50 watt tube amplifier with seperate transistor preamp box. The tube amplifier contained a built-in output transformer package.

The tube amplifiers use the long discontinued type 7868 output tubes (2 per channel) which are now very expensive to buy. Other tubes are two 12AX7 preamps and one 5U4GB rectifier tube.

Preamp circuit board assembly information.

# 601-03758 Preamp PC Board Assembly, models MM3 and MM4

# 602-03758 Preamp PC Board Assembly, models MM5 and MM6

Recapping this board:

Both versions use five 5 uf @ 25 volt axial electrolytic capacitors (C6L, C6R, C23L, C23R, C28). Use modern 4.7 uf to replace the 5 uf ones.

One 100 uf @ 6 volt Axial electrolytic capacitor (C26). Use a modern 100 uf @ 16 volts to replace it.

Only a total of six axial lead electrolytics need to be replaced.