Magnavox 3FM021 table radio

[Motorola minion]

A friend found this little gem at a yard sale years ago. I am preparing to sell it after I acquired an older Magnavox table set that is a REAL beast from Brettzky.
All of us know the common Mag radios with a beveled front and tuning meter in the center of a wood panel.
These parallelogram-shaped sets were often paired with a companion speaker.

This chassis is 65-02, which is an improved version of the 65-01 still in the older cabinet. Still is a basic series wired AM-FM using a 50EH5 output tube, a slightly improved 50C5. This set was between a transition from Sams 568-9 to 610-8 - added AFC and a degenerative feedback loop from 50EH5 plate to 12AV6 cathode. Bypassing the 68 ohm audio output cathode resistor with a 47 mf cap improved bass only a teeny bit, so I left it alone. Many times, radios sound a bit better with a bypass cap added there.

There were only three paper caps, three electrolytic caps and a selenium rectifier on the initial hit list. I replaced only the first 100 mf electrolytic cap in line with a 250v rated, BECAUSE a silicon rectifier diode replaced the selenium, as that 150v rated cap section tested marginal and failed as voltage would rise to 160 DC until tubes warmed up. The other two sections 100 and 50 mf were fed by resistors and tested good ESR, so if those were to fail, only a resistor would get crispy.

This receives well and sounds good, requiring minimal alignment. Not quite a Zenith but as good as any other. I do not understand why there is just a 2.2 mmf cap for the crossover feeding two small cone tweeters each rated 3-4 ohms from the 4x8 oval speaker

[TC Chris]

I do not understand why there is just a 2.2 mmf cap for the crossover feeding two small cone tweeters each rated 3-4 ohms from the 4x8 oval speaker

Remember that Maggie's corporate philosophy was "voicing," fiddling with parts & values until it sounded they way they thought it should. That cap may have pleased an engineer's ear.

Chris Campbell

[Motorola minion]

I do not understand why there is just a 2.2 mmf cap for the crossover feeding two small cone tweeters each rated 3-4 ohms from the 4x8 oval speaker

Remember that Maggie's corporate philosophy was "voicing," fiddling with parts & values until it sounded they way they thought it should. That cap may have pleased an engineer's ear.

Chris Campbell

Indeed, I wonder how much fun those Engineers had developing the filter networks. It seems like this was a punt and Im investigating
Maybe its all math but you CAN hear the difference. Transfer function = output / input so... when considering harmonics, those numbers get really long