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Well, that's the one I bought to make a gift for my old man. With the "magic eye".
So I took the chassis out. As a minimum, the tuning cap belt is broken, so I've ordered one from Adamsradio - thank God for it. Almost every single radio is listed there. Bought various Zenith belts, now the WR-212, all listed by name, easy!
Well, started to look: someone tried to repair it some time back.
http://www.nostalgiaair.org/PagesByModel...024271.pdf
This is the schematic.
Now if you look at the caps, all the electrolytics are 8uf, 12uF or such.
Imagine my surprise: the guy put in 150uF-300uF-75uF.....yikes.
So, I think I have'em all, but good thing I am checking it.
Can't trust people nowadays ![Icon_smile Icon_smile](https://philcoradio.com/phorum/images/smilies/icon_smile.gif) Not with the caps.
Speaker was obviously repaired - some glue on the back of the cone and, for whatever reason, a piece of felt was put in between the cone and one of the frame spots. I wonder why....hopefully it sounds OK, otherwise more money goes to some Speaker shop.
Well, more will come tomorrow.
This is the radio.
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With those caps, you had better check the 5Y3. It could be junk by now.
(This post was last modified: 01-28-2013, 12:35 AM by Phlogiston.)
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That is a handsome set!!!!
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Yes indeed, that is a very nice looking set
Gene
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It's a funny thing about cap replacement....
I got a model 655 tombstone awhile ago. When I took the chassis out I saw that it had been re-capped. The values in some cases were more than twice the original. I left it "as is" just to see what happens. This path has led to mischief in the past, but I like to live on the edge.
So... It plays like a CHAMP!!! Zero hum and excellent sound. Hmmm....
Regardless, I still replace with values close to or slightly higher than original. Many radio-types claim that more capacity equals more filtering, and the 655 may be an example of this. I would rather not push the envelope when re-capping.
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Wow, that is a nice looking table set. I definitely would snag one if I found it for the right price!
No matter where you go, there you are.
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TA
This is from the guy you referred me to this November.
Phlogiston
I will check all of them toobs. This is why I have the Hickok.
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I think that the speaker may be a replacement, possibly from the 1940s or 50s. The pincushion style speakers weren't that popular outside of Philco back in the mid 30s, most 6 and 8'' ones used a round frame.
Regards
Arran
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I also feel like it is a replacement, I just thought that the field coil types were no longer popular in 50s when perm magnet types replaced them.
Actually looking at the e-bay link I posted here you can see the original was a round one. I guess if I feel like it I could try to buy it, the model is written there - 72203-5
(This post was last modified: 01-29-2013, 09:42 PM by morzh.)
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Well, done with the electrolytic caps and the main voltage divider resistor chain; only some had to go, the rest is fine.
Many smaller caps have been already replaced. Many resistors are within 5% to 10% so I will keep them.
The volume regulating resistor is gone - when I opened it, I realize that there is a barely noticeable hair crack around the tap, and this what makes it to produce the infinity.
I tried to use a pencil, and after 5 minutes rubbing the resistance came back, and I applied some Deoxit, but after the very first turn the discontinuity came back.
Luckily I located some exact (found the thread in ARF) replacement in Oldradioparts, tomorrow will order it.
The tubes are mostly good; 6A8 is a bit weak, even on the English scale, but I need to fulfill 20 buck min. order in ORP, so I will pick one up.
The previous restorer also rewired the Tuning Eye circuit as he replaced 6G5 with 6E5, and obviously it is more sensitive. No biggie. Will try 6E5 first, but want to get 6U5/6G5. Judging by my Zenith 6E5 works acceptably in the circuit for 6U5 (actually 6T5 but they are electrical equivalents), though the sector does not open all the way as it should, but I could live with it. 6U5 today is about 30 bucks if new. And the 6E5 I have is either new or very good as it is as bright as it gets. I tested it on the Hickok.
Well, so far this is it, will keep at it; need to get the volume control first.
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Sounds like you are making great progress my friend Keep up the good work!!!
Terry
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Oh, and another good news is: despite that 150uF cap across the rectifier, the much feared 5Y3 failure did not materialize: the tube's alive and and passes the Hickok test, if not with flying colors (one half in the middle-green another - borderline but still green), then may be still on the solid side.
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Received the potentiometers with taps for the volume from Oldradioparts, ordered two just in case - they are cheap. The exact replacements were made by Mallory and Central Lab.
NIB.
The terminals were oxidized as heck. Had to clean them.
The shafts are twice as long - obviously purposed for multiple radios. But they are made of aluminum (good idea for a replacement part) and so was easy to saw off - I do not even have a hacksaw, just the blade, so I held the blade in my hand and sawed it off in about 2-3 minutes, filed it a bit...done!
But guess what.
After the Deoxit on my origina pot dried up, it sucked the graphite inside the crack as it was drying (or it is my theory). Now the contact is restored and the rotation of the wiper does not break it.
But....my rule is, you do not break your agreements with God. If it took you to buy the new pots to fix it, keep the new ones in and relocate the old one to your local museum.
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Well.
Installed the pot, change the 6A8 tube (the old one was testing low although I suppose it works and I will keep it just in case).
Turned the variac slowly...the dial bulbs lighted up...one did not...happened to be the clip that it uses to clip to the chassis.
Started looking for stations.....hum....realized I was on the wrong band, went to the Broadcast....plays beautifully. Even with the non-native (and probably repaired) speaker.
Put the tuning eye in...I did not re-do the 6U5 hookup, thinking that 6E5 will probably work worse with it, so I left it in place.
It works just fine now, and is quite bright.
Need to clean up the top of the chassis just a tad...some dust, not too much.
It was probably aligned as at least the broadcast stations are right where they should be and the sensitivity with a small piece of wire is great.
Well, good for me, I thought it would take me another couple of weeks, as it is only during weekends that I can devote some time to these projects. No more than 2-3 hrs during weekdays.
I guess my dad will have to accept it with the foreign speaker, not that I am going to emphasize it too much, but him being a former EE, I may divulge some details of it. It may take too long to get a chance to acquire the proper speaker.
All in all, with exception of those oversize caps 20 times of the proper value, the guy put the right parts in otherwise, so I only had to replace a few resistors, electrolytics, two tubes (6F5 had the grid cap separated which I found during the Hickok test - now it works, now it doesn't and 6A8 with low pentode section mut. conductance) and the tuning belt.
Back in the cabinet it goes.
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I would try to resolder the grid cap on the 6F5, if it tests good otherwise it's worth salvaging.
Regards
Arran
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