: 1934 Motorola W-58  ( 284 )

TJ

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1934 Motorola W-58
« : February 04, 2021, 09:12:30 AM »
My uncle, by marriage, has his grandfather's Motorola radio, and he remembered his grandpa still using the radio in the barn/shop back in the 1960s and '70s. 

It had stopped working a while ago, and when I delivered the '61 Imperial to them, he asked if I could get this radio working again, and a 37-60 Philco Cathedral he also had.

The Philco was easy to get up and running again, just needed capacitors and a new power cord; all of the resistors tested pretty close to spec.

The Motorola, however, was a mess.  It has had a LOT of work done to it over the years.  There were no original capacitors left, the volume/power switch had been replaced, the tone control knob died and was completely bypassed.  The tubes all tested OK, none were in the red, however, someone had put a type 77 in the 78 socket, they are both wired the same, but have different performance characteristics.  I ordered a replacement 78 and am waiting for it to arrive

I replaced all but the 2 mica caps, and all but 2 resistors.  The 500k resistors were all testing in at about 1.7 Meg. There was also modifications to the circuitry, which I left in place as most of it was for the tone control bypass. But some of it, when following the schematic, did not match at all.   Not sure if it was a change from the factory, but I replaced the components with what was installed, not the schematic to be safe.  It works alright, I peaked the IF/RF cans the best I could, the adjustments on the tuning capacitor are rusted tight, so I can't dial it in the greatest.

This seems to be a pretty rare little radio, the only info I can find on it is from RadioMuseum.org https://www.radiomuseum.org/r/motorola_w58.html

My Consoles:
1962 Motorola SK112CW-FM, All original tubes
1958 Magnavox Continental - DIY Concert Grand!
1957 Magnavox Brittany - Amp 148 Magic!

Bill

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1934 Motorola W-58
« #1 : February 04, 2021, 06:33:37 PM »
It sound like you had a lot of fun with the Motorola.  It's never fun, but always a challenge when someone was in there before you especially if the did not know what they were doing, or they were a cobbler.  I'm glad it turned out ok and it now plays again.


Bill

TC Chris

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1934 Motorola W-58
« #2 : February 04, 2021, 11:37:25 PM »
Hey, a fun project, and a rare radio that works.  85 year old technology....   I read somewhere that the Soviet Union--remember them?--continued making vacuum tubes because of their durability.  In a nuclear blast, the electromagnetic burst would fry solid-state electronics but vacuum tubes would survive.  (Another view was that the Soviet Union was just way behind in technology).

Chris Campbell

TJ

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1934 Motorola W-58
« #3 : February 05, 2021, 06:55:14 AM »
Hey, a fun project, and a rare radio that works.  85 year old technology....   I read somewhere that the Soviet Union--remember them?--continued making vacuum tubes because of their durability.  In a nuclear blast, the electromagnetic burst would fry solid-state electronics but vacuum tubes would survive.  (Another view was that the Soviet Union was just way behind in technology).

Chris Campbell

They were also using and making germanium transistors in the 1980's and early '90s.  From what I have read about their technology, is that most of it was reversed engineered, so much so, that you could take the American made component, put it in the russian equivalent, and it would work. I will go with the theory that they were behind as they were  reverse engineering their tech.  And making it compatible with western technology meant that they would be able to use pirated tech if they needed instead of having to reverse engineer everything.

It will be interesting to see how this radio performs once I get the proper 78 tube in.  Even though they are wired the same, they are not shown to be subs of each other in the tube substitution manuals.

I sent a video of it running to my uncle, and he is very excited.  He said the last time it worked for him, it barely got a single radio station, and you could hardly hear it through the static. Where they live, they are about 3 miles from an AM transmitter that still play classic rock, with a simulcast on FM. This may get some use in his shop, and with the modern components in it, should work pretty reliably.
My Consoles:
1962 Motorola SK112CW-FM, All original tubes
1958 Magnavox Continental - DIY Concert Grand!
1957 Magnavox Brittany - Amp 148 Magic!

TC Chris

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1934 Motorola W-58
« #4 : February 05, 2021, 07:17:33 PM »
Make sure he has some wire hanging around for an antenna.  Doesn't take too much but likely better if it's away from fluorescents and LEDs.

Chris Campbell