12-19-2019, 04:01 PM
Now the speaker. The correct speaker for the late version 90 is nearly impossible to find. The push-pull 47 pentodes need a much higher impedance speaker than the 45 triodes used in the early version 90. I had planned to make do with an early version speaker but as it turned out, the one I had, has a bad output transformer. The cone is bad also and I had planned to replace it. So, up to now, I have been using the speaker out of my Philco 20 for testing the chassis.
[Image: https://live.staticflickr.com/65535/4924...5f12_k.jpg]100_0200 by Steve Davis, on Flickr
I removed the transformer, the cone and the field assembly. I then cleaned and painted the "pie pan".
[Image: https://live.staticflickr.com/65535/4924...69a6_k.jpg]100_0202 by Steve Davis, on Flickr
Steve
[Image: https://live.staticflickr.com/65535/4924...5f12_k.jpg]100_0200 by Steve Davis, on Flickr
I removed the transformer, the cone and the field assembly. I then cleaned and painted the "pie pan".
[Image: https://live.staticflickr.com/65535/4924...69a6_k.jpg]100_0202 by Steve Davis, on Flickr
Steve
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