Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

It's Alive!!!
#16

I've completely dismantled it, cleaned, oiled, examined, and can't see any issue with it. The windings don't seem to be damaged in any way, everything spins very freely and smoothly. When I first got it it was even weaker than it is now, but I still can't get it to 78 rpm.

I'm not sure about these things but I'd guess the fact that it's an old Canadian 25 cycle motor would mean I could probably never get it spinning at the correct speed?



Here's a few images of the beast....

[Image: http://i835.photobucket.com/albums/zz278...f7c367.jpg]

[Image: http://i835.photobucket.com/albums/zz278...3697af.jpg]
#17

Is this the original or the replacement motor? If anything a 25 cycle motor should be trying to take off down a runway on 60 cycle as AC motors are governed by line frequency, if it's too slow then the mechanical governor I see on one end may have something to do with it.
Regards
Arran
#18

This is the original motor. I've tried running it with the governor completely backed off and it still wouldn't pick up enough speed.

Even if I were to get this motor running freely, I'd never get it to spin at 78 rpm, right?
It would naturally want to spin faster?
#19

I don't see any solution here other then to try finding a 60 cycle replacement for this changer, that may take some time. The only real way to see if the motor is working properly is to find someone with a VFD (variable frequency drive) to test it with, but everything that I have read and heard is that an AC motor should run faster at a higher line frequency not slower. There were pockets of 25 cycle service in the U.S, most notably in upper New York state around Niagara Falls, I think there were some in Pennsylvania as well, so it isn't a uniquely Canadian thing. In fact much of Canada was always on 60 Cycle power, like in Quebec and the Prairie provinces.
Regards
Arran
#20

I think the issue is impedance. If you increase the frequency, you also have to increase the voltage. But, then the motor would run to fast (if there is no governor). VFDs control both frequency and voltage.

Steve

M R Radios   C M Tubes
#21

Maybe you could use a bucking transformer to boost the voltage up on the motor.
Terry
#22

I'm going to keep my eyes peeled and my fingers crossed and hopefully I'll find one in the future.
for now I'll either put the geared motor back in or try and modify a motor and idler assembly to fit.

@Arran, Thanks for the additional info, I had no idea about the 25 cycle outside of Canada. Learn something new every time I log into this place!




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco Model 38-7: what caps & resistors do fail typically?
Welcome to the Phorum Martin. I count about 9 paper caps, the 3 electrolytic caps and 2-Y2 safety caps to replace th...RodB — 09:44 PM
Part numbers to model cross
Jim, We have this index put together by Dale Cook but I don't think that is quite what you are looking for. The Parts...klondike98 — 09:37 PM
Philco Model 38-7: what caps & resistors do fail typically?
Yep the dim bulb test is OK but I'd definitely replace all those electrolytics before I did it. Since those #47 conden...klondike98 — 09:18 PM
Philco 42-345 Restoration/Repair
The resistor is a 2.2 Meg, it was the last one I hadn't replaced. The broadcast is coming in after replacing it.osanders0311 — 09:09 PM
Philco 42-345 Restoration/Repair
What does the resistor measure? I think it should be 3.3 Meg. If the oscillator coil has continuity and the resistanc...RodB — 09:03 PM
Philco Model 38-7: what caps & resistors do fail typically?
Good idea to check the coils... then I'll get hold of an incadescent light bulb and see what happens when the unit is sw...Musaeum — 08:49 PM
Philco 42-345 Restoration/Repair
I have that same set, ain't too much shortwave I like anyway.....it is a good AM DX set. PaulPaul Philco322 — 08:32 PM
Philco Model 38-7: what caps & resistors do fail typically?
Welcome to the Phorum, Martin! Open a new thread in Philco Electronic Restoration when you begin working on your 38-7. ...GarySP — 08:28 PM
Philco Model 38-7: what caps & resistors do fail typically?
Welcome to the Phorum! :wave: Here's the schematic for that radio from our digital library: Something to do bef...klondike98 — 08:05 PM
Philco Model 38-7: what caps & resistors do fail typically?
Hi all, on vacation in Montreal,  a friend of mine showed me a Philco Model 38-7 console radio from the 30ies. Mechan...Musaeum — 07:21 PM

[-]
Who's Online
There are currently no members online.

>