Ron's RCA T7-5 Electronic Rescue
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Ron;
I'm not sure what thread pitch these cans used but it may have been American Pipe thread, if not it was just a large SAE machine thread, in either case you might be able to clean up the threads with a die from a tap and die set. I'm glad to see that you got it out relatively intact.
Regards
Arran
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[Image: http://www.philcoradio.com/images/phorum...-5_051.jpg]
Here is the third electrolytic, all restuffed and waiting for me to solder the proper connector on the positive end. Then it will be mounted on the chassis.
It contains two Solen Fast 8.2 uF caps connected in parallel for a total of 16.4 uF. Slightly less than 18 but should be OK given the very loose tolerances of electrolytics back in the day.
Why didn't you use two 10s, or a 10 and an 8.2?
Simple - those combinations would not have fit in this can. As it was, I had to modify the top of this can to make it work. Even then, two 8.2 uF caps just barely fit inside. They are truly jammed in there.
I checked for shorts and there were none. Then I tested its capacitance - 16.74 uF. 
I am hoping to fire this radio up for the first time this weekend.
Oh, by the way, I shall face another problem soon - how to get the dial pointer off so that I may replace the dial scale. That pointer is really frozen on the shaft thanks to rust. Any suggestions welcome.
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Ron Ramirez
Ferdinand IN
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Maybe a tiny drop of Liquid Wrench, gun oil?
Paul
Tubetalk1
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Penetrating oil, of your choice, and a pair of duck bill pliers, the flat kind with no texture, to grab the hub of the pointer. Leave the oil on it overnight, then add a little more, then leave that for a few hours, then tap the center sharply with a screwdriver handle, then grab the hub of the pointer (not the needle) and give it a twist, once it moves then pull and twist at the same time. If it does not loosen up and come out I don't know what to suggest, maybe wrap a string around the hub of the pointer and see if that will give you some purchase, or work it's way between the pointer and the shaft.
Regards
Arran
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Okay!
Tonight, I finished up the third electrolytic can and installed it.
I also finished connecting the speaker wires, the B- leads, and the 6K7 RF tube grid cap lead.
In addition, I went ahead and installed the 15K resistor in place of the original 13K (R20).
And, of course, a new AC cord and a 1930s AC plug were installed.
I tested all seven tubes. Of the seven, four required replacement. It had a 6V6GT in the audio output socket and it failed its test anyhow; it was replaced by a metal 6F6. The 6K7GT IF tube was weak as was the 6F5; the 6H6 had one dead section. All were replaced with metal save for the 6H6 which was replaced by a 6H6GT as I did not have a metal 6H6 in stock. But that's okay...I intend to open up that little top hat 6H6, gut it, and install two 1N34A diodes inside. I will then put it back into the radio.
Two of its original Cunningham-Radiotron metal tubes tested good and remain in the set: the 6K7 RF amp and the 6A8 mixer-oscillator.
Here's how things looked by the time I had installed everything:
[Image: http://www.philcoradio.com/images/phorum...-5_059.jpg]
[Image: http://www.philcoradio.com/images/phorum...-5_060.jpg]
Edit: Photos replaced with better photos.
Ready to try out...
--
Ron Ramirez
Ferdinand IN
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I had a hard time removing the speaker from the cabinet. Of course, two of the three speaker mounting nuts were rusted to the decorative speaker screws.
Fortunately, a little PB Blaster and some gentle persuasion soon took care of that problem.
I connected the speaker, connected my little 12 foot antenna, plugged the T7-5 into my Variac, slowly brought it up and...
It's Alive!
[Video: https://youtu.be/ZaKu0BDiAG4]
Less than three weeks...not bad after the last project.
[Image: http://www.philcoradio.com/images/phorum...-5_055.jpg]
Of course it isn't finished yet. There is still the matter of the dial pointer, and replacing the dial scale. In addition, the speaker sounds awful - much like a Philco 20. There is a good reason for that...
[Image: http://www.philcoradio.com/images/phorum...-5_054.jpg]
Look, Ma, no spider! And so the voice coil is rubbing the pole piece like crazy. The cone is not in very good shape, either. Looks like this calls for a recone job.
Well, this weekend I'll see what I can do about the dial pointer, in between my other weekend projects. I'm just happy to have this one basically done! 
--
Ron Ramirez
Ferdinand IN
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Excellent work, Ron! You brought that one back from the dead in short order 
Should sound excellent once you re-cone the speaker.
Think I got my dial scale from Radio Daze. I installed it without removing the pointer. Mine would not budge when trying to remove it, so I carefully slipped the pointer through the hole in the old dial scale and slid it up and off. I repeated that with the new scale, sliding it down into place instead. Believe I cheated a bit on the new one and enlarged the center hole a bit to make installation easier. You won't see the hole once the escutcheon is installed.
The dial cover on mine came from Mark Palmquist. It's a nifty looking dial with a sunburst effect.
Greg V.
West Bend, WI
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Thanks, Greg! I'm very happy that this project went smoothly and reasonably fast, and especially that it came on and played the very first time.
I think I am going to let Sound Remedy in NJ recone the speaker. I've suggested this company to others but have never used their services myself. I've seen good feedback about them, notably from Mike (morzh) who has used them more than once, I believe.
That dial...it looks sort of Philco-ish...but looks good. I'll order a new dial scale and the decals needed for this set's cabinet this weekend. I will be ordering a new dial cover from Mark P. as well - the dial cover on my set is badly yellowed and somewhat more opaque than translucent.
Oh yes, and there is still the matter of how to re-mount the Fahnestock clip for the antenna.
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Ron Ramirez
Ferdinand IN
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It doesn't show very well on the dial picture but the three main arcs for the different bands are different colors. The decal for the bandswitch has three different colored dots representing the A, B, and C bands. That's something Philco didn't do on their sets of this era with this type of Amber dial...use color on the dial scales.
Greg V.
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Yup, I've looked at the Radio Daze replacement already and saw the colors... ...and that they match the decal used on the cabinet above the band switch. But the font used for the numbers and lettering look the same as 1936-38 Philco.
Speaking of the band switch...
I had initially set the band switch to extreme counterclockwise because that's where I expected the AM band to be. Not so! That is the high SW position. AM is extreme clockwise, with low SW or "police" band in the middle. Seeing the RCA band switch decal on the Radio Daze site confirmed that for me.
Something else I found odd...the dial is arranged backwards compared to other radios of the era I have worked with; the low end of each band is on the right and the high end on the left.
For what it's worth, some 1937 and 1938 Philco dials have blue and red lettering on them in addition to black. I think most of the Radio Daze repros have black lettering for black and blue, and red where red should be. The 38-690 dial I recently purchased for my 38-690 project was that way; no blue lettering at all, it was black instead.
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Ron Ramirez
Ferdinand IN
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I have removed the dial scale, the same way that Greg removed his - by turning the tuning condenser about halfway open, removing the four push pins that held the scale in place, and then carefully slipping it off the pointer.
Greg, how did you fasten your new dial scale to your T7-5? All four of the push pins that held my dial scale in place were rusted, and all four broke when I removed them.
I've hit the pointer with more PB Blaster where it is fastened to the tuning condenser shaft. With the dial scale out of the way, it is now easier to get PB Blaster into the point where pointer meets tuning condenser shaft.
I also removed and disassembled the ball bearing tuning assembly. It is made very much like Philco radios with two-speed tuning, and came apart the same way. It is soaking in naptha now to degrease everything. I have the knobs soaking in Evapo-Rust as the metal springs inside the knobs are badly rusted.
I attempted to rebuild the little top hat 6H6 tube and install two 1N34A diodes. Everything went well until I discovered that the top of the tube no longer fits properly onto the base.  I could have sworn that there would be enough room for the diodes inside there...
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Ron Ramirez
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Ron, you might be able to use the top off of a taller metal tube to cover the diodes.
Steve
M R Radios C M Tubes
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When I was young, we had the console version of this radio. I don't remember too much about it, though I remember the dial looking exactly like your T7-5. I remember listening to the 1964 Indy 500 on that radio when an accident claimed the lives of Dave MacDonald and Eddie Sachs.
Steve
M R Radios C M Tubes
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Sorry to hear about the dial scale fastener pins being so badly rusted , Ron. Mine were in good condition so I was able to reuse them. I think I would have pop riveted the new scale on mine if they wouldn't have been reusable.
I'm finding just the opposite with 6H6 tubes...I have a number of the little top hat style metal ones but finding the coke bottle style 6H6G's are more difficult.
Greg V.
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Pop rivets...good idea! Thanks Greg!
Steve, I have an idea in mind for the 6H6...I'll let everyone know if it works out...
Speaking of 6H6, Greg, I too find the 6H6G (ST type) to be difficult to find. I happened to have a couple 6H6GTs (tubular glass) in my tube stash, so one went in place of my half dead 6H6. I don't have any spare metal 6H6 tubes.
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Ron Ramirez
Ferdinand IN
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