12-13-2019, 09:14 PM
I installed two 4.7uf film capacitors in the other can to be used as the input filter. I then sprayed a coat of lacquer on cans and installed them in the chassis.
[Image: https://live.staticflickr.com/65535/4921...b6bc_k.jpg]100_0192 by Steve Davis, on Flickr
After one more good looking over, I'm ready for the "Smoke Test". I hooked up the speaker and brought it up slowly.
[Image: https://live.staticflickr.com/65535/4921...9ba0_k.jpg]100_0194 by Steve Davis, on Flickr
Oh no, I have a problem! The screen grid on one of the 47s is glowing bright orange! I quickly turned the radio off. Now, this is what happens when you get old. I bought this speaker on eBay and for some reason, I forgot to test it! One half of the primary of the output transformer is open. The speaker is not correct for this chassis anyway. This one is for an early 90 but, there is almost no hope of finding a speaker for a late 90. I will probably wind up buying universal replacement transformer. So for now, I pulled the speaker out of my Philco 20 as it is the only P-P speaker that I have that has the correct field coil resistance. So I try again. Wow! Its talking! I'm surprised, I figured the alignment would be so far off (remember I had the tuning condenser completely apart) that it wouldn't pick up anything but, I have three or four stations coming in weakly. Maybe tomorrow evening I will have time to do the alignment.
Steve
[Image: https://live.staticflickr.com/65535/4921...b6bc_k.jpg]100_0192 by Steve Davis, on Flickr
After one more good looking over, I'm ready for the "Smoke Test". I hooked up the speaker and brought it up slowly.
[Image: https://live.staticflickr.com/65535/4921...9ba0_k.jpg]100_0194 by Steve Davis, on Flickr
Oh no, I have a problem! The screen grid on one of the 47s is glowing bright orange! I quickly turned the radio off. Now, this is what happens when you get old. I bought this speaker on eBay and for some reason, I forgot to test it! One half of the primary of the output transformer is open. The speaker is not correct for this chassis anyway. This one is for an early 90 but, there is almost no hope of finding a speaker for a late 90. I will probably wind up buying universal replacement transformer. So for now, I pulled the speaker out of my Philco 20 as it is the only P-P speaker that I have that has the correct field coil resistance. So I try again. Wow! Its talking! I'm surprised, I figured the alignment would be so far off (remember I had the tuning condenser completely apart) that it wouldn't pick up anything but, I have three or four stations coming in weakly. Maybe tomorrow evening I will have time to do the alignment.
Steve
M R Radios C M Tubes
