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Philco 38-690 electronics restoration.
#58

Some not so good news. 
Tonight I thought to try to power up with rectifiers which requires the speakers connected.
So I unbolted the large speaker (had to remove two clarifiers first) and saw this

   

Which caused that:

    .

So.....I think, considering the value of the radio, warrants reconing. If they do recone this type.

But, I thought, why not try it anyway to see the functionality?
So first I went straight to check the output transformer. Sure enough. Opened primary all three wires. Then I saw the fuse. It was good but oxydized. I wiggled it, and one half of the primary conducted. The other did not.
But even that is weird: the half shows 1.4 kOhm while the sch says 200 Ohms each. The transformer is original.

So. Need to recone the speaker and the new output pushpull xfmr.

Will need to find out the speaker impedance to pick one.
Good news: the field coil is good.

This will delay me a month.

Sigh.....

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.


Messages In This Thread
Philco 38-690 electronics restoration. - by morzh - 04-12-2017, 07:19 PM
RE: Philco 38-690 electronics restoration. - by morzh - 06-09-2017, 06:54 PM



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