08-25-2023, 04:06 PM
I was able to figure out how the speaker cone and driver/coil assembly went into the speaker and remove it from the speaker frame. The cone was held in place by several strips of felt behind, on the side edge and infront of the cone and finally a metal rim screwed in place to hold it all firm. Thus when I removed the screws holding the driver/coil assembly to the frame, the cone and driver all came out together.
[Image: https://www.dropbox.com/scl/fi/mwd5epicd...fz8y&raw=1]
[Image: https://www.dropbox.com/scl/fi/62vv5lp1s...i260&raw=1]
[Image: https://www.dropbox.com/scl/fi/rdeq6x1ej...innu&raw=1]
[Image: https://www.dropbox.com/scl/fi/h32a9as92...tkxs&raw=1]
This allowed me access to some of the connections for the wires in the coils. At first I thought I was going to get lucky and solve the coil continuity problem with a simple reflow of solder around the main speaker lead connections on the top of the driver assembly. It did solve one connection issue but there are others. You can actually get an ohm meter lead onto the wire just as it enters and leaves the coil as well as at a point midway through each coil and after checking all the various combinations to try and figure out where there might be a wire break, I find that there is a problem in all sections of the coils. Unfortunately, the dirver assembly appears to be a press fit together in multiple places. They probably originally had a jig of some type to place the various parts in and then pressed the driver frame together. I do not believe I can get it appart and successfully back together again so I've decided not to try. My next decision is whether I put it back together or fit it with a 1930s PM speaker with an audio transformer mounted someplace. (this is what Sonny, the radiolaguy, did with his, see: https://www.radiolaguy.com/Images/coneSp...425-Ri.jpg)
[Image: https://www.dropbox.com/scl/fi/mwd5epicd...fz8y&raw=1]
[Image: https://www.dropbox.com/scl/fi/62vv5lp1s...i260&raw=1]
[Image: https://www.dropbox.com/scl/fi/rdeq6x1ej...innu&raw=1]
[Image: https://www.dropbox.com/scl/fi/h32a9as92...tkxs&raw=1]
This allowed me access to some of the connections for the wires in the coils. At first I thought I was going to get lucky and solve the coil continuity problem with a simple reflow of solder around the main speaker lead connections on the top of the driver assembly. It did solve one connection issue but there are others. You can actually get an ohm meter lead onto the wire just as it enters and leaves the coil as well as at a point midway through each coil and after checking all the various combinations to try and figure out where there might be a wire break, I find that there is a problem in all sections of the coils. Unfortunately, the dirver assembly appears to be a press fit together in multiple places. They probably originally had a jig of some type to place the various parts in and then pressed the driver frame together. I do not believe I can get it appart and successfully back together again so I've decided not to try. My next decision is whether I put it back together or fit it with a 1930s PM speaker with an audio transformer mounted someplace. (this is what Sonny, the radiolaguy, did with his, see: https://www.radiolaguy.com/Images/coneSp...425-Ri.jpg)
