1964 Motorola 3 ch console - compressionaire bass
Posted: Wed Feb 21, 2024 9:52 pm
After buying this classic model for my 50th birthday in 2003, it sat unrestored until recently. This is not a Drexel cabinet, mostly poplar and other hardwoods with walnut veneer, finished a bit too dark for that wood. There must be a hundred screws inside this cabinet having many reinforcing braces that solidify the massive boxes formed within.
A few months ago, I finally gave it the slow power-up to give an indication of any major issues. After using it for a few months, the issues compounded and motivated me to do it right. The biggest problem was dirty controls and pushbuttons, so it took much disassembly which is aided by the blocks seen in pictures. I left tuner/preamp connected and lifted them to access parts, clean controls/pushbuttons and tube sockets. No tubes tested weak or gas/shorts. Even the electrolytic capacitors tested OK. After replacing red-block wax caps, a few electrolytics and resistor or two, it was done enough for me.
In the pictures you can see a dull control panel with pitted aluminum sheet for labels. I cut out a piece of sheet plastic to overlay the control labels, then added a 12-volt LED tape underneath the casting, bringing a new look to this otherwise too-plain preamp.
I also have 1962 and 1963 3-channel Motorola consoles, which both have more interesting controls. The 62's had metal, lighted-dial preamp knobs which was remarkable in comparison to other makes. The 63's ditched the lighting and used cast-metal knobs for its preamp but changed from a slide-rule dial to separate round dials. The 1964 uses small plastic knobs, too little for fat fingers to comfortably operate if pushed the whole way down. This was helped by the overlay, raising knobs to let light out.
The VM-made record changer is separate project, but it might be easy if that oddball cartridge is OK. This model was last good tube Motorola IMHO, as it has 340 volt DC supply and big audio transformers. Forget the 11 speakers, as nobody else did that many! After this one was a very tamed-down coffee table and some other budget offerings using tubes, post 1964 Motorola solid state models sold poorly or weren't good enough to be survivors like the 1959-63 models were.
A few months ago, I finally gave it the slow power-up to give an indication of any major issues. After using it for a few months, the issues compounded and motivated me to do it right. The biggest problem was dirty controls and pushbuttons, so it took much disassembly which is aided by the blocks seen in pictures. I left tuner/preamp connected and lifted them to access parts, clean controls/pushbuttons and tube sockets. No tubes tested weak or gas/shorts. Even the electrolytic capacitors tested OK. After replacing red-block wax caps, a few electrolytics and resistor or two, it was done enough for me.
In the pictures you can see a dull control panel with pitted aluminum sheet for labels. I cut out a piece of sheet plastic to overlay the control labels, then added a 12-volt LED tape underneath the casting, bringing a new look to this otherwise too-plain preamp.
I also have 1962 and 1963 3-channel Motorola consoles, which both have more interesting controls. The 62's had metal, lighted-dial preamp knobs which was remarkable in comparison to other makes. The 63's ditched the lighting and used cast-metal knobs for its preamp but changed from a slide-rule dial to separate round dials. The 1964 uses small plastic knobs, too little for fat fingers to comfortably operate if pushed the whole way down. This was helped by the overlay, raising knobs to let light out.
The VM-made record changer is separate project, but it might be easy if that oddball cartridge is OK. This model was last good tube Motorola IMHO, as it has 340 volt DC supply and big audio transformers. Forget the 11 speakers, as nobody else did that many! After this one was a very tamed-down coffee table and some other budget offerings using tubes, post 1964 Motorola solid state models sold poorly or weren't good enough to be survivors like the 1959-63 models were.
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