The PHILCO Phorum
650 PM Speaker Replacement - Printable Version

+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: 650 PM Speaker Replacement (/showthread.php?tid=11572)


650 PM Speaker Replacement - RodB - 02-07-2015

Hello, another newbie with my first post. I'm restoring a Philco 650 and would like advice on replacing the speaker with a PM speaker. The original cone is trash. I think I can replace the field coil with a 1.2k 10 watt resistor since the field is not the power supply choke. The field coil measures 1175 ohms. I also would swap the audio output transformer for a 14k center tapped primary/8 or 4 ohm secondary for the PM speaker. Are there any other changes I should consider?

Rod

RE: 650 PM Speaker Replacement - klondike98 - 02-07-2015

Hi Rod, Welcome to the Phorum!!  I'll post a link to the 650 schematic to aid others in providing you advice.  You could also consider reconing the speaker.

RE: 650 PM Speaker Replacement - RodB - 02-07-2015

Thanks Bob, already have a quote for reconing. Just like to consider all options.

RE: 650 PM Speaker Replacement - RodB - 03-07-2015

So here's my dilemma; I have a Philco 650 speaker that has a badly damaged cone and an open in the output transformer (P/N 32-7078 ) primary. I looked into replacing the two components with a PM speaker and associated output transformer. Cost is around $80-$100. Another option is to rewind the transformer and re-cone the speaker. Cost, about $70. Questions arise in rewinding the transformer: 1. How do I open the transformer core? 2. What can I use to remove the paper coverings on each layer of the windings? 3. Is the primary wound on the inside, outside or intertwined with the secondary?

Does anyone have this transformer or a good replacement? I don't see going ahead with the rest of the radio till I get this resolved. (What would Marconi do?)

RE: 650 PM Speaker Replacement - Ron Ramirez - 03-07-2015

Please place an ad in the Wanted section of this Phorum.