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IF Can Test Result
#1

Hey All,
Easy question for you guys.  I tested an IF can and have questions on the results.  
The AM primary is .3 ohms out of 12 ohms but has continuity.  The AM secondary also has .3 ohms out of 12 ohms but has continuity.

The FM primary is 6 ohms out of 15 ohms but has continuity.  The FM secondary is 19.7 ohms out of 20 ohms has continuity assuming this is good.

The ohms are low so are the windings bad?  But they all have continuity, so are the windings good?  Is the can good or bad?

Lots of questions.  Thanks,
Steve
#2

If indeed 12 ohms are required, and your meter isgood, and you are measuring what you think you are messuring, then 0.3 ohm is wrong.
Inspect the winding for looks of being burnt.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#3

Thanks I will.  I'm thinking this radio may be a lightning victim.
#4

It will depend on "how" you are measuring .... in circuit? ... out of circuit? ... coil wires disconnected and measured? ... trimmer caps still connected?

Maybe you could share the model number and your test method?
#5

.pdf schematic (11).pdf Size: 129.77 KB  Downloads: 111
.pdf schematic (12).pdf Size: 98.01 KB  Downloads: 93

It's a 47-1227.  

I worked on it a year ago.  It powers up but receives nothing.  I replaced all the capacitors, resistors, and electrolytics.
Still receives nothing.  Ran out of knowledge.  The antenna and ocsillator coils have continuity.

I heard somewhere that the 1st IF is known to be bad on this model. 
When I tested it, I left it wired in the chassis.  I followed the wires out of the can and tested where they were connected.  I did take out the tubes. 
I tested cans 2 and 3 the same way and got good readings. Cans 2 and 3 have continuity too.

That's where the confusion started.  How can the 1st IF have continuity but low ohms?  Could the Capacitors in the can be burnt?

The antenna coil looks like it was repaired.  The cabinet is beautiful all original.  I was thinking it was a lightning or power surge victim. It fried and put in a corner.

Rambling on.....sorry.

Steve




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