Philco 70 Cathedral Speaker
Posts: 4,816
Threads: 54
Joined: Sep 2008
City: Sandwick, BC, CA
(12-05-2014, 11:05 PM)Steve Davis Wrote: Quote:I hope he will, he did not claim it was working....
Mike, The guy responded that he was unable to test the speaker so he sold it as-is. Well, I checked his other auctions and he has several radio related items listed, that tells me he must have some knowledge about this sort of thing. So I just don't believe his story. I think he had tested the speaker and was dumping it on Ebay.
Other Mike, I have been studying the pictures of your winding machine, I will have to make one. A pulse width speed control would work much better. I also need to build some sort of fixture to press out the pole piece. I'm not sure if I want to use a hydraulic jack or just a large bolt.
Steve Pressing out the pole piece is the easy part, pressing it back in so its straight is another matter, though not too difficult with a proper press. I can't imagine that they needed much force to press them together but who knows, at least they didn't weld them in too like an RCA speaker.
I think that if it is a universal style brush motor you could probably limit the voltage to control the speed, like with a variac. For an AC only motor that involves using a variable frequency drive, which is out of the question for this sort of thing. A fellow on you tube used a cordless drill, which has a speed control built in, with gears I think, and rigged up a counter to count the number of turns, it usually is not a problem finding a good cordless drill to butcher for this, most people toss them out after the battery dies.
Regards
Arran
Messages In This Thread
RE: Philco 70 Cathedral Speaker - by Arran - 12-09-2014, 01:36 AM
Users browsing this thread: 1 Guest(s)
|
|
Recent Posts
|
|
An attempt to remove the Field Coil from a G speaker
|
| Mike;
I've only run into a speaker with an open filed coil twice, and they were on newer speakers from the 1940s. One ...Arran — 12:48 AM |
|
An attempt to remove the Field Coil from a G speaker
|
| Arran
Yes, this is my plan for now and what do I got to lose, this is not even the speaker from this radio, but one o...morzh — 10:44 PM |
|
An attempt to remove the Field Coil from a G speaker
|
| Mike;
I would unwrap the field coil, and see if maybe there a break near one of the ends, like where the coil wire att...Arran — 10:23 PM |
|
An attempt to remove the Field Coil from a G speaker
|
| ...and this is what I did. I fed a little LT into the screwholes with a small brush, and a little on the rim next to the...morzh — 09:52 PM |
|
Philco 40-120C Restoration
|
| I combined the two 40-120C threads together as we like to keep the discussion of the same radio together. It helps with...klondike98 — 09:36 PM |
|
Philco 40-120C Weak, Distorted Ouput
|
| Just checked were I buy tubes price is four dollars. So living in Florid we have a local source for tubes. David David — 09:14 PM |
|
Philco 40-120C Weak, Distorted Ouput
|
| The higher voltage may be due to higher mains voltage. My mains run 120-125AC when the set was new mains would be 110-11...David — 09:09 PM |
|
Philco 40-120C Weak, Distorted Ouput
|
| Thank you for your reply. I pulled a speaker from a Philco 41-221 and received the same result. I used a signal tracer t...bluecap — 08:45 PM |
|
Philco 40-120C Weak, Distorted Ouput
|
| Have you tried a different speaker?
How did you trace the distortion?
How do you know it is weak? What is the reference?...morzh — 08:33 PM |
|
Philco 46-480 Electronic Restoration
|
| Amen to that! Every time I think I’ve captured them all, I realize that there’s another error. My goal is to finish with...jrblasde — 07:00 PM |
|
Who's Online
|
There are currently 1572 online users. [Complete List]
» 1 Member(s) | 1571 Guest(s)
|
|
|
|
 
|
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
