Philco Model 16B Cathedral
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City: Woodland, CA.
Mine appears to have a layer of dryer lint or dust bunnies, and all the tube shields are missing... And i think Chuck is away from the store... Havent received confirmation on my order.. Meanwhile, its beer-thirty..
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City: Wood River, Il.
I have worked my way down to the volume control circuit. It does not match the schematic. What's in there looks to be very old but may not be original. It is not the work of the hacker, as it is too professional for him. I am just wondering if there are any known published mods to this circuit. It works, and sounds good, with the exception of the tone control circuit, which has very little effect. When I rebuilt the tone circuit I rebuilt to the schematic. The volume control does have the tone compensating tap, which is connected per the schematic. (The tone control circuit is one of the things that had been hacked badly by the last guy, so I don't know what was there before he got into it!)
I am debating going back to the schematic "stock", or simply replacing the OT resistors and keeping the mods, as they are working. (Other than the tone control.) In looking at the under chassis photos that I have seen, the area in and around the volume control don't look like mine. There are some molded caps (mica?) attached to the chassis. None of which appear on the schematic or parts list.
Chris H
N9WHH
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Chris,
look up the service bulletin. I do not have the link but if you dig up my thread on 16 (last year) it is there.
The volume circuit has been changed several times.
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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City: Wood River, Il.
Hi Morzh,
Thanks for the info. I thought that I had seen something on changes and updates somewhere, I just couldn't remember where. I do remember reading your posts on rebuilding your 16B, but no matter what I put into the search, I was not able to find it until tonight. Thanks
I did finally figure out the tone control caps that the guy on You Tube was talking about, Sunday morning. I wish I had seen it first, as it would have saved a lot of time and head scratching. I did finally figure out that the one Bakelite block, #80, as I recall, was shown in error in the info that I have on the bakelite blocks. Even though I now have it wired per the schematic, it does not have any real change in how things sound. I am going to have to noodle on the changes sheets and see if I can figure out what is going on. The #80 Bakelite is not shown on my parts layout though. It took a little while to figure that one out too. I think just getting away from it for a little while helps bring things to light. It will take a while to digest what is going on with the changes to the volume control too.
Again, thanks for your help and guidance.
Chris H
N9WHH
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It looks like this is the thread - and the post where Ron links to the 'Changes in Models" document. Very helpful to have a read through that.
http://philcoradio.com/phorum/showthread...#pid112386
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Money orders sent..... Awaiting my literature.. Meanwhile, doing a bit of reading on prior experiences around here.. .
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Stall, once you start on your restoration it would be helpful and clearer to those who are trying to answer questions if you started your own separate thread, e.g. "Stall's 16B restoration" or something like that. In threads where two people are asking electronic questions about two different radios things can get confusing.
Cabinet restoration questions would go in the Cabinet Restoration section also in a new thread.
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I totally agree Bob
At this point, i was just gathering info and resources. When i remove that first screw, i promise it will be in a new thread. I can see where 2 (although same) radios in different stages of repair would get confusing in one thread..
Thanks again..
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City: Wood River, Il.
Thank you, Nathan, for adding the thread. I would have tried doing so, if I knew how. The changes and bulletins from Nostalgia Air are very helpful. I don't know how I missed it, as I thought I had found everything from that site regarding the 16 and 16B.
I went thru the volume control circuit, last night, and while all the components were there, the way they were wired didn't make any sense! What a mess! After a little experimentation I got it wired correctly. The tone control circuit is still another matter. While I believe I have it wired correctly, it still has very little, if any, effect. I still need to spend a little time on that area, but haven't gotten thru the complete recap and the OT resistor replacement yet. Maybe that will help.
One thing I have noticed is that the old resistors, with the metal caps on the ends, are almost always still within spec, while the dog bones are not. So I am keeping many of those in the circuit. Am I likely to have problems with these in the future?
Thanks for all the help!
Stall, good luck with your project.
Chris H
N9WHH
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City: Jackson, NJ
Chris
When I asked you earlier about the volume control circuit, if it was hacked, you said the audio circuit (I thought this is how you referred to the volume control) appeared to be stock.
If it were stock, I would not touch it as, as I noted before, there are mods to it reflected in the notes.
One of them is, when the volume pot top pin (input, coming from the detector) is connected via a capacitor, while the pot itself is higher value than shown in the sch.
The detector output is loaded with a resistor before that capacitor.
Make sure you find the appropriate circuit sch before you touch it.
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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Glad that document was helpful Chris.
I've noticed the same thing about the 'metalized type' resistors being almost always the correct value. I leave those alone.
The 'standard type' resistors are often wildly off. the funny thing is that Philco supplied both types as replacement parts:
http://philcoradio.com/phorum/showthread.php?tid=12651
Reproductions of 'standard type' resistors aren't too difficult to method. I outlined the process I use here:
http://philcoradio.com/phorum/showthread...#pid118654
(Sorry that you'll have to click on the photos to see them now that Photobucket changed their policies).
It's based on Steve Davis' tutorial: http://philcoradio.com/phorum/showthread.php?tid=5501
the difference being polystyrene tubing rather than a pen -and hot glue rather than jbweld.
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City: Wood River, Il.
Hi Morzh,
The components appear stock, (volume control: 2 meg, and part values match my schematic) they just were not wired per my schematic, nor any other that I could find. Some previous repairman or the last hack job "rearranged" the wiring somewhat. What I have now matches the schematic per bullitin 165b (I think, going by memory here) and sounds great.
The tone control still needs work. As I have said, I don't hear any difference in the switch settings. It is possible that the changes are very subtle and my ears are not good enough to hear the difference. It is also possible, (and more likely) that I have misswired it. I still need to dig into this some more.
Hi Nathan,
I have reviewed both posts for recreating the older resistors look. I suppose I am not enough of a "purist" to go thru this process. I do restuff the Bakelite blocks, and try to maintain the correct values per the part number stamped on the side, when ever possible. Same for the filter cans, but I will put a label on the cans indicating they have been rebuilt, with a date. I figure most people are not going to see the underside of the chassis anyway. If they do, they can tell, at a glance that resistors have been updated. I also put a label on the chassis indicating it has been serviced with a date here too. These radios are for me anyway, mostly to indicate to me what has been done. I also keep my notes and marked up schematics for my later reference, (because I won't remember).
I will be keeping most of the metalized resistors from here in. I have not seen resistors like these on other brand radios, (Zenith, RCA, etc. ) I just thought they were parts made by Philco. Much like the Bakelite blocks and the tubular capacitors I have found on earlier Philcos.
Thank you, both for all the help!
Chris H
N9WHH
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(07-26-2017, 10:20 AM)Nathan Slingerland Wrote: (Sorry that you'll have to click on the photos to see them now that Photobucket changed their policies).
We can't do that - I tried, and after the wheel spun and spun a long time, it finally showed me...the same "Please update your account to allow 3rd party hosting" image.
Ain't Photobucket wonderful.
To all of you, I am so sorry that I ever recommended them. I had no idea at the time that this would happen.
--
Ron Ramirez
Ferdinand IN
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Yeah - I was wrong about that. I think I was fooled by this because the browser caches images. My own images load if I log into my Photobucket account and view them - then if I try to view my thread on PhilcoRadio.com they usually appear correctly. But it doesn't help anybody else with other people's photos.
Posts: 79
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Joined: Dec 2014
City: Wood River, Il.
I worked thru the tone control issue. I had missed a capacitor value change in one of the bulletins. Tone control works so that I can hear the difference now.
I moved on to removal of the tuning condenser, mostly to clean it up. But the rubber bushings needed replacement as well. My old trusty Weller 250 watt gun made short work of desoldering the braid from the mounting screws.
I installed the new tuning dial, from Radio Daze. I used 1/8" x 1/16" grip copper pop rivets to attach the dial to the tuning wheel. I am not real sure that I would mount it that way again. The rivet will interfere with the tuning counter shaft unless it is peened down on the inside. I looked into small machine screws too, and they present the same problem. If you peen the rivet too tightly the plastic dial may crack.
The tuning dial looks good, except, the lettering is printed on the front side. There are already signs of the lettering flaking off in places. Because the sliding mask does have felt pads for contacting the dial, I am a little concerned that the lettering might be rubbed off. I suppose time will tell on this.
Does anyone have a recommendation for a replacement rubber "tire" that will work on the dial drive wheel? I have already replaced the rubber components in the rest of the tuning drive, with O-rings. I have installed a large cross section O-ring on the tuning dial meter, for now, but don't know how well it will continue to work.
The tuning shadow meter works, kind of. The coil is good, and I can see some movement when tuning strong stations, it isn't right. I think part of the tuning vane has broken off. There is only a short piece remaining at the pivot point, maybe 1/4"-3/8" long remaining. I have it on the bench right now, and have been staring at it for a while. It looks way too delicate for me, with my hand shake, to attempt a repair. I am thinking that something is better than nothing, if I were to screw it up by attempting a repair.
Regarding the tuning meter coil, it looks like all the B+ for the IF is going thru the coil. Is there a mod out there for shunting the coil to remove some of the load from the coil, and still have a reasonably working meter. (I assume adding any shunt will remove the sensitivity of the meter.)
Thanks for reading.
Chris H
N9WHH
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