12-13-2021, 07:33 AM
I remember a couple of Motorola 3 Channel consoles when I was a kid, and fixed one once. I think that the "3 Channel" concept was popular with Motorola consoles and rather unique to them. The theory was to concentrate the program to the high power, usually push pull center channel while the left and right channels provide the stereo ambiance. I don't remember if there were any low / high pass filters dividing up the programming between center and left / right channels. One theory, very popular now with home surround sound systems, is that people cannot determine the direction of sound lower in frequency than 300 Hz.
Based on the tube layout sticker on your unit, the center channel using 2 6BM8 Tubes (Triode preamp, Pentode Output) accentuated the lower frequencies, while 2 6BM8 Triode Pentode tubes provided single end left and right channels. a 12AX7 served as a Stereo Preamp Tone Control Amp. Total "undistorted" power of this Unit was likely 10 watts. True HiFi? No. Sweet? Yes!
The turntable on this unit is a VOM (Voice of Music), a very popular turntable, not as high end as the Collaro used by Magnavox, or the better Garrards, but very popular and of good quality. There is a Voice of Music Website and much can be found on the internet regarding these turntables. The biggest issues for this and any turntable of this vintage are dried grease, deteriorated Capstan Wheel (the "tire" that drives the turntable) and deterioration of the ceramic cartridge. Magnetic stereo cartridges were reserved for very expensive, true HiFi systems such as Fisher, Scott, etc., that cost one quarter to one half the cost of a new car in the late 1950s to very early 60s.
This is a a rather high end portable for the time, as very few portables of any manufacturer were transformer powered. Fix this up, this is a true keeper!
As a child, we had a Voice of Music stereo portable, physically larger than your Motorola. Each speaker cabinet, hinged to the main cabinet, held 2 6" Speakers. The Amp was a 12AX7 preamp with 2 50L6 SE Output amps. The output transformers were large for this type of amp and it was powered by a solid state (silicon) half wave voltage doubler power supply. My brother bas the speakers, but the rest of it was lost, as it was obsoleted by the much newer, more powerful solid state stuff. I would have saved the amp but its layout did not lend to repackaging. Considering how much people on eBuy pay for SE Amp Output transformers, let alone tube amps, even of this type, I am kicking myself for not saving it, not just from getting some cash for it but because another person would have enjoyed it, as much as we enjoy our antique electronic finds.
Based on the tube layout sticker on your unit, the center channel using 2 6BM8 Tubes (Triode preamp, Pentode Output) accentuated the lower frequencies, while 2 6BM8 Triode Pentode tubes provided single end left and right channels. a 12AX7 served as a Stereo Preamp Tone Control Amp. Total "undistorted" power of this Unit was likely 10 watts. True HiFi? No. Sweet? Yes!
The turntable on this unit is a VOM (Voice of Music), a very popular turntable, not as high end as the Collaro used by Magnavox, or the better Garrards, but very popular and of good quality. There is a Voice of Music Website and much can be found on the internet regarding these turntables. The biggest issues for this and any turntable of this vintage are dried grease, deteriorated Capstan Wheel (the "tire" that drives the turntable) and deterioration of the ceramic cartridge. Magnetic stereo cartridges were reserved for very expensive, true HiFi systems such as Fisher, Scott, etc., that cost one quarter to one half the cost of a new car in the late 1950s to very early 60s.
This is a a rather high end portable for the time, as very few portables of any manufacturer were transformer powered. Fix this up, this is a true keeper!
As a child, we had a Voice of Music stereo portable, physically larger than your Motorola. Each speaker cabinet, hinged to the main cabinet, held 2 6" Speakers. The Amp was a 12AX7 preamp with 2 50L6 SE Output amps. The output transformers were large for this type of amp and it was powered by a solid state (silicon) half wave voltage doubler power supply. My brother bas the speakers, but the rest of it was lost, as it was obsoleted by the much newer, more powerful solid state stuff. I would have saved the amp but its layout did not lend to repackaging. Considering how much people on eBuy pay for SE Amp Output transformers, let alone tube amps, even of this type, I am kicking myself for not saving it, not just from getting some cash for it but because another person would have enjoyed it, as much as we enjoy our antique electronic finds.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
Best Regards,
MrFixr55
