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Old 02-11-2011, 04:03 AM
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bandersen bandersen is offline
RCA 741PCS
 
Join Date: Mar 2009
Location: Chicago, IL
Posts: 8,109
Thanks for the kind words. I really would like to give it a try someday. I'm a bit behind in my projects so it may take a while.

I've been reading a lot about open coils in old Philcos so I've been dreading getting out the ohmmeter. Well tonight's the night.

I was pleasantly surprised that all but two of them are very close.
One that's way off is the secondary on the last 2nd IF can. The schematic calls for 85 and I get 47.
I'm going to leave it alone for now and see how it sounds. I figure it could be a mistake in the schematic.


The other problem is an open section in the antenna coil
The 10 ohm section is fine, but the lower 0.7 is open.
There's some coating (wax?) around the lower section of the coil so it's a bit hard to inspect.
I believe this is where the ground connection is made. So somewhere between here and an inch or so above is the break.
I'll try to clean off the crud with alcohol and find it.


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Last edited by bandersen; 02-12-2011 at 07:50 PM.
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