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41-240 Power Transformer
#5

Kenneth is right.  Unless its been serviced recently the electrolytic caps, paper caps and some resistors will need replacement before you power it up again.

You can find a free schematic here: http://www.nostalgiaair.org/pagesbymodel...013402.pdf

and a clearer one here: http://www.audiophool.com/Philco.html  (you need a djvu reader for this one)

or a very clear one from Chuck for a few bucks: http://www.philcorepairbench.com/schematics.htm

The rubber wiring in this model will likely be bad and need replacement see: http://www.philcoradio.com/phorum/showth...?tid=14959

Caps at #52 should be Y2 safety caps, See: http://www.justradios.com/safetytips.html

The power transformer can be checked to some extent by checking the windings for their resistance (radio should be unplugged).  In the schematic below you see the power transformer.  If you place your ohm meter leads on the rectifier plate sockets (take the tube out) you should see something around 620 ohms.  Keep one lead on one of the plate sockets and place the other on the chassis.  You should see an open circuit (infinite resistance). If you see that, the secondary HV windings are good and there is no short to the chassis.  Similarly, you can check the primary windings by putting the ohm meter leads on the plug (with the set on-off switch in the on position).  You should see something around 13 ohms.  The filament secondary windings can be checked in a similar fashion although that will appear almost as a dead short since its resistance is only 0.2 ohms.  If these measurements all look good it could have been a short someplace else in the radio caused the power xformer to heat up.  They can have some wax/tar melt out and still function but its best to figure out why that happened.  Others on the Phorum are much better trouble shooters than I am but this is a pretty basic first look.  

[Image: https://dl.dropboxusercontent.com/u/5462...former.jpg]


Messages In This Thread
41-240 Power Transformer - by ccbaker13 - 10-23-2016, 04:11 PM
RE: 41-240 Power Transformer - by ccbaker13 - 10-23-2016, 08:42 PM
RE: 41-240 Power Transformer - by klondike98 - 10-23-2016, 09:04 PM
RE: 41-240 Power Transformer - by Radioroslyn - 10-23-2016, 09:31 PM
RE: 41-240 Power Transformer - by ccbaker13 - 10-24-2016, 07:13 AM
RE: 41-240 Power Transformer - by ccbaker13 - 10-24-2016, 09:34 PM



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