Philco Model 512 Mandarin Red - LOC Terminal - 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: Philco Model 512 Mandarin Red - LOC Terminal (/showthread.php?tid=25194)
+- 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: Philco Model 512 Mandarin Red - LOC Terminal (/showthread.php?tid=25194)
Philco Model 512 Mandarin Red - LOC Terminal - jjfritz5528 - 08-18-2024
What is the purpose/Function of the LOC terminal at the upper left of the schematic?
I'm sure there is a good explanation, but I don't know.
It connects to the 110V input power thru a small capacitor?!
Thanks In advance
John
RE: Philco Model 512 Mandarin Red - LOC Terminal - MrFixr55 - 08-19-2024
Not going from any document, but my semi-educated guess is to connect the "Ant" terminal the "Loc" terminal as a substitute for the long wire antenna commonly used at the time with these radios. It sems that Philco used a technique common to some aftermarket "plug in" antenna gimmicks that purported to use the house wiring as an antenna. I remember seeing these even in the 60s and 70s in magazines for use as a substitute for TV antennas. Definitely use a Safety cap for #35 when restoring this set and consider placing on the transformer side of the switch. Note the absence of any EMI filter caps on the power line (See JR Bladse's 46-480 thread). Hopefully the local stations were stronger than the noise from the vacuum cleaner's brush type motor , arcing across high tension cable insulators duirng rain and any other electrical interference. This radio is ca 1927-1928 or so, and many electrical appliances were coming into vogue at the same time that radio was.
Hope this helps!
RE: Philco Model 512 Mandarin Red - LOC Terminal - Radioroslyn - 08-19-2024
Well it does a couple of things. It will shock you if you touch your fingers between LOC & GND, it acts as a line filter, and back in the 1920's it might have been used as an antenna connection. Wouldn't try it now too much interference. The best this to do is connect it to GND on the chassis and connect that to earth gnd (not thru the house wiring if you can help it)
de N3GTE
RE: Philco Model 512 Mandarin Red - LOC Terminal - morzh - 08-19-2024
It is on my 86.
Used it as an antenna (yes it was used like that before they realized the perils).
I used a Y-cap, 10nF.
RE: Philco Model 512 Mandarin Red - LOC Terminal - jjfritz5528 - 08-19-2024
Thanks to ALL!
I hadn't thought about using a Safety Cap here. I just finished re-doing the Filter Cap can, so I'll snip out the regular 0.015mf and replace. I'll also include a jumper to the Ground terminal. I always ground directly to the nearby water pipe.
RE: Philco Model 512 Mandarin Red - LOC Terminal - morzh - 08-19-2024
ANYTHING used at the Mains needs some safety rating, and ANYTHING that can be touched by a human has to be Y-rated and limited in value to the safe touch current level.