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I just refinished recapping two Philco 46-420 radios. One of the radios was missing the antenna so I made a new one matching the number of loops in the other. They both play quite well pulling in stations across the dial. Would you recommending aligning the radios or leave well enough alone. I have not aligned a radio before but the instructions seem to be pretty straight forward and I do have a signal generator.
Thanks - Jim
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Why not? adjustments should be very minor so if you feel confident do one. Then compare with the other. May the best tube win!
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I agree. You may or may not squeeze anything more out of it but until you run thru the procedure you'll never know. In the worst case its good experience and a reference of how its supposed to behave for when you encounter a set that has true alignment problems.
-Bill
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Most definately. It probably needed alignment long before your re-capped it anyway due to component aging.
Get the service bulletin to be sure you align it correctly.
Chuck
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I will give it a try. The instructions say to "connect the signal generator to the standard Hazeltine loop model 1150 and loosely couple to the receiver loop". How do I connect the RF output of the signal generator to the radio?
Thanks for all your help. - Jim
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For touch-up work like this just place the generator lead close to the loop. You should pick up enough signal to work with.
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First, I want to thank everyone for the help. It's great to have a place to get some expert advice. You are bringing many radios back to life!
I aligned the radios and they seem to work well. When I place my hand on one of the radios near the antenna, the volume increases significantly. The other one is not affected as much. the one that is sensitive is the one that I installed the new loop antenna. I double checked the number of loops, they are the same. I did use a slightly larger gauge magnet wire. The volume is sufficient but not as loud as the radio with the original antenna. I should probably leave it alone but now it bugs me. Is there a way to tune the new antenna?
Jim
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My Hasletine loop is about 25 turns on a TP cardboard and a .1 cap place next to the set. Close enough or what?
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Jbaker Wrote:First, I want to thank everyone for the help. It's great to have a place to get some expert advice. You are bringing many radios back to life!
I aligned the radios and they seem to work well. When I place my hand on one of the radios near the antenna, the volume increases significantly. The other one is not affected as much. the one that is sensitive is the one that I installed the new loop antenna. I double checked the number of loops, they are the same. I did use a slightly larger gauge magnet wire. The volume is sufficient but not as loud as the radio with the original antenna. I should probably leave it alone but now it bugs me. Is there a way to tune the new antenna?
Jim
If you had an inductance meter it would be a piece of cake. Otherwise you're limited to trial and error. If my thinking cap is on straight you need to add more inductance if your hand increases the volume. If you're willing to dive in try adding about one turn at a time while listening on the LOW end of the band, around 550. You're probably not off more than a turn or two. In my playing around I've found those loops can be critical to about half a turn if you're being precise. Be sure to tweak the antenna trimmer cap at the HIGH end, usually 1400 or so, each time you make a change. If you run out of trimmer range you'll know you have gone too far.