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Adjusting the 66 compensators
#16

Good going Jim!!!Icon_thumbupIcon_thumbup
Glad the little compensator adjustment tool worked out for you as well. I'll take a few pictures of what I've made and post it so others can make them as well.
#17

Radio is not as done as I'd like it to be. AM works just fine but the SW is totally dead. I have rechecked all the bandswitch contacts as well as the coil connections and all appears fine. I'm thinking its the 6A7 not oscillating at the higher frequency but all my spares either start to reproduce that D**n squeal on the AM or work the AM band just fine with no change for the SW. Short of ordering a new tube is there anything else I'm missing?
#18

Just checked the oscillator with a Zenith 1000. With the Zenith set at just below 7 MHZ I tuned thru the SW band and found the null at Just above 7 MHZ on the Philco, actually around 7.1 MHZ. Interesting too is that if I tapped on the tuning knob on the Philco I could hear the thumping in the Zenith.
#19

Getting back to this radio I fired it up again and that D**n squealing was back on the AM band. Decided to resub a 6A7 and redo the connections on all the tube shields. Now I can recieve stations on the AM band without squeal except one. Stations I can recieve here are 760 from Detroit, 800 from Canada and the the locals which are 1230, 1370 and 1470. All come in fine except 1230.

That one has the squeal on it. Strange since 760, 800 and 1370 are higher power stations than 1230 and 1470 is a lower power station. Just another thing to try and figure out. Also, still not getting anything from the SW band. Thinking that it might have been disabled during WWII somehow. I've ordered the lit from Chuck so I can go thru this with a fine tooth comb.
#20

After going thru this radio again I still couldn't figure out why the SW would not work. I was thinking that this might have been a modified radio from WW2 where they disabled the SW but could not find anything so I decided to go back thru the alignments one more time.

All went well with the 470KC until I heard a loud squeal then dead silence. My substitute 6A7 gave up for some reason. Placed my original 6A7 back in and redid the alignments. I can now recieve all stations below 1500KC without problems but above that on the AM band I'm getting that motorboating again and still nothing on the SW.

I still think its the 6A7 thats giving me the problems so I have put out a feeler for a NOS one, not an used/tested one. I hope that this will fix my problems. Plus I need to get some chassis mounting bolts for this.
#21

After replacing the 6A7 with a NOS one I'm still stuck with the motorboating above 1500KC and no SW. Guess this thing will sit on a shelf until I feel like diving back into it. Just too frustrated at this point in time to put anymore effort into it.




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