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[Image: https://dl.dropboxusercontent.com/u/5462...chdown.jpg]
Real progress today. I decided to alligator cable in the replacement IF transformer that I got on ebay. Put all the tubes in and fired it up with the dim bulb unit. Nada. Bulb not lit at all, tubes not warming up, no sound...nada. I forgot about that open resistor that parallels the pilot lamp and is in series with the tube filaments. That will surely keep it quiet.
OK...so alligator in the 22 ohm 2 watt resistor and try again. Yes! Now I'm getting nice clear sound from it.
[Image: https://www.dropbox.com/s/7cb9pxn1571olf....jpg?raw=1]
Now my remaining task will be to take that replacement IF transformer apart, do some surgery and cram it into the smaller can that goes with this set. At least I now know it can work.
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Kirk is looking at that and wondering
How youdidnt get shocked
But he's getting at shock from looking king at it
Some day, and that day may never come, I will call upon you to do a service for me. But until that day, accept this justice as a gift
mafiamen2
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Got to thinking about that 22 ohm 2 watt resistor and realized its not the correct replacement. I measured 0.295 amps (which is right on for the filament circuit) and that means that resistor is dissipating almost 2 watts so I should increase it to at least a 5 watt resistor.
"Fit the round peg into a square hole" ...well not quite but I started looking at putting my replacement IF coil into the original can as Terry suggested earlier in this THREAD.
[Image: https://www.dropbox.com/s/thd88dvb1cvjt1....jpg?raw=1]
The replacement I found has larger diameter coils and a different mounting system. I'll have to think about this a bit, it will be close but I think I can make it fit. I'll post pics of the fun...
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well shoot...the coils came apart nicely enough and I was able to mount the new coils on the old compensator cap board with a bit of carving BUT the dang thing is just a bit too large to fit into the old can. Even cutting off some of the frame won't do it, the actual coils are just large enough to be a problem. Back to the drawing board. At least I know the radio works now.
[Image: https://www.dropbox.com/s/ec95mqf1e8rhdt....jpg?raw=1]
[Image: https://www.dropbox.com/s/h449u3v4jmi1x4....jpg?raw=1]
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Just wondering Bob, if you could use a larger IF can that is similar to your original off a junk chassis.
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Mike, this chassis is pretty compact and the place where this can is located has very little additional room.
[Image: https://www.dropbox.com/s/1vueucrzpsav1x....jpg?raw=1]
I have another IF transformer coming that I think has a smaller dia set of coils on it that hopefully will fill the bill. Are we having fun yet... 8)
Now that you mention it though... the plate that the can is mounted on also covers the tuning capacitor and frame. I might be able to raise that plate some with some standoffs to give myself a little more room if I had to. There is probably another inch or so of room if I did that. I'll try the coil that is coming and if that doesn't work out will go to the KCMike plan B.
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(12-14-2016, 07:05 PM)sam Wrote: Kirk is looking at that and wondering
How youdidnt get shocked
But he's getting at shock from looking king at it
Terry has a few alligator clips too,
Good work on..... That? hahaha
Times I have been electrocuted in 2021
As of 1/01/2021
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Last year: 6
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While I'm waiting for that new IF coil I started taking the cabinet apart so I can strip it. The thin brass plates came up easily. I actually was able to pull the brass brads out with my fingernails but I'm missing one brad. I have the 3 metal plates for the front of the radio, but am missing one that belongs on the back. That one will likely be hard to find. It will be one of those things you put on your "watch for it to come up on ebay or show up at a swap meet" list. I should be able to get the plates cleaned up so they look better.
[Image: https://www.dropbox.com/s/f8q2dl3wv8xwtm....jpg?raw=1]
I was thinking the top of the set was a veneer but the more I look at it the more I think its a photofinish type of product that will come off when I strip. We'll deal with that when/if it happens.
[Image: https://www.dropbox.com/s/0yp8g87xiv06ff....jpg?raw=1]
The grill cloth is in decent shape although very dirty. Since Kenneth sells a reproduction of this cloth I think I'll put that into it. I could probably sell the original cloth on ebay for ... $1000, $2000...??
[Image: https://www.dropbox.com/s/s38utsp83vbukm....jpg?raw=1]
If you recall from the beginning of the thread, the door on the left (facing the radio) was someone's DIY door that was better than nothing but not really very good when you look closely. I'm hoping to do better...time will tell.
[Image: https://www.dropbox.com/s/dbnyybqei7zzfc....jpg?raw=1]
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Great job so far Bob! Anxious to see how you replicate that door.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
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(12-19-2016, 02:51 PM)Eliot Ness Wrote: Great job so far Bob! Anxious to see how you replicate that door.
So am I!!!!
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Book matched photofinish? Why have 4 pieces of veneer if it is photofinish....
Hmmmmmm tht is a hard one.. Strip it and see.. you can put some real bookmatch in if it was photofinish...
Looking good.
Send me your addy and I'll send you mold making supplies. I have some of it that is contaminated so I cant use it for knobs but you will have to paint the door so inner bubbles wont be an issue for you to use it......
Me...
Times I have been electrocuted in 2021
As of 1/01/2021
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Thanks Kirk but I'm going to try a wood reproduction first.
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Back to working on the IF coils. I got an IF coil that has a smaller diameter coil that the one I tried first. Must be out of a late 30s early 40s set since the rubber it crumbling. It has a bakelite frame holding the trimmers and the coils. The replacement is on the left, the original on the right:
[Image: https://www.dropbox.com/s/1yj8bugmn75wxx....jpg?raw=1]
I was able to separate the coils from the trimmers by cutting it with a hacksaw:
[Image: https://www.dropbox.com/s/c4sel12afmvi9i....jpg?raw=1]
Unfortunately the bakelite did not respond well to drilling. I was trying to drill a hole to mount it onto the original trimmer frame.
[Image: https://www.dropbox.com/s/dptxym7lie4f4w....jpg?raw=1]
Some plastic tubing and liberal use of epoxy and I was able to get the coils mounted to the original trimmer framework.... MacGyver would be proud.
[Image: https://www.dropbox.com/s/t3yv0n1hm20s45....jpg?raw=1]
The coil wires and new lead wires were soldered to the trimmer lugs and the whole thing fit nicely into the original can...
[Image: https://www.dropbox.com/s/835o6n7066ht96....jpg?raw=1]
Here it is fully mounted onto the chassis:
[Image: https://www.dropbox.com/s/pyqpsuz90q4xqs....jpg?raw=1]
...and a final view of the restored underside of the chassis:
[Image: https://www.dropbox.com/s/kdz4mq05ozul06....jpg?raw=1]
Its playing nicely now and has yet to be aligned so may be even better. Next time... more on the cabinet
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Looks good and great problem solving on the coil.
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MacGyver is standing aside in awe and is nervously chain-smoking......great job on that IF xfmr. Gosh, I hate these "elephant in an efficiency appartment" chassis types.
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.
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