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Found a 38-40 table model, and I'm making it the first radio repair I've done in several years. I fooled with the hobby in high school and a few years after, but took a hiatus after marriage, kids, etc.
The cabinet is in fair shape, the electronics appear to be untouched, except for a missing tube (6K6G). Two knobs were missing, but I found them inside the cabinet when I removed the chassis (this is good!)
The other thing I found is a piece of black string about 2 1/2-3 inches tied to a spring. It was floating loose in the cabinet with the missing knobs. I'm not sure what it does, or if it's even part of the radio.
The tuning dial is intact, but has a solid, straight, break in a clean line. I think it is best left as is. I suspect that I will regret fooling with it. The tuning window is empty, with the dial behind it. It has no plastic window, but photos I've found don't appear to have one either.
All this leads me to suspect that the piece of string tied to a spring is a vertical tuning indicator, hung in the middle of the tuning window? I'll take a closer look at the possibilities as I work through the recap, etc.
I'll be starting the recap and testing later this week. Any caveats or warnings about this model are appreciated. I am picking up the general pointers and advice from carefully reading this forum and others.
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If it's a 38-40T it should have a round escutcheon with a piece of glass mounted in it to protect the dial. The dial is a sort of amber colored opaque plastic. Is this what you have?
Regards
Arran
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Black string with a spring on it? Sounds like a dial cord to me. I'm not familiar with the Philco 38-40T, are there any small pulleys on the dial, or near it?
The artist formerly known as Puhpow! 8)
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Yes, the dial is amber colored opaque plastic. An older technology plastic (no surprise), apparently quite brittle. It is mounted on the chassis and turns with the tuning knob. My first thought was that the string is part of a dial cord as well, but the dial turns just fine. I'm just setting up the bench, and the only light is an overhead bulb (bench in basement next to washing machine). I'll be adding a real bench light and that will make everything much easier.
The dial window, in the wooden case, has a solid amber colored plastic plate with a design on it. When the chassis is in the cabinet, the dial turns and is visible through a small hole in the plastic plate. This appears the same as the photos I've seen on line. Although, the protective glass you mentioned may have been there originally. That sounds easy enough to replace, if necessary.
Thanks for the replies.
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I have a practical question about parts. I understand that there must be a variety of opinions, but I am looking for the general consensus. Is it general practice, when buying replacement parts, to remain as true as possible to the original appearance, or to use the modern equivalent? Of course, both methods require staying true to the original ratings. I'm talking about caps and resistors, not the external parts. I am planning a drive to a nearby electronics supply this weekend for a variac and the initial caps that I know should be replaced. I know that both methods will work, but I want to keep to some norm of the generally accepted practice.
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If i'm not mistaken you need to buy modern caps to replace what is there. NOS ( new old stock) are to old and lose their values from just being old. New ones will be more reliable. If you want to preserve the look of the old caps you can stuff the old ones with the new caps so they look the same.
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You'll want to replace the electrolytic caps, the paper caps and, the bakelite caps. Make sure you get equivalent or greater voltages when buying caps. Most modern electronic supply places don't carry caps with high enough voltages (the ones local to me don't), so you might have to order them online. Any mica caps in your set are probably ok.
Here is link to the schematic and parts list for your radio.. http://www.nostalgiaair.org/Resources/vi...013251.pdf
Don't forget to check all the resistors too.
The artist formerly known as Puhpow! 8)
(This post was last modified: 08-13-2013, 03:52 AM by Jamie.)
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Restuffing the original paper caps with modern replacements really does preserve the under chassis appearance. The paper caps in the photo have the corresponding mylar caps inside
[Image: http://philcoradio.com/phorum/attachment.php?aid=2107]
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Warren, thanks for the warning. I knew about the importance, but not just anybody would have!
Restuffing, now that's an idea I would not have thought of.... Thanks PuhPow and Mondial. Also, thanks for the schematic, I already found that one as well. It should be sufficient.
I'm not personally worried about the original appearance underneath. I'm thinking that staying true to the design is important (i.e., don't duct tape in an iPod). But, if somebody follows me in 20 years and sees the work, they will know somebody else was through. (hopefully they won't shake their head and swear at what they find...)
I expect that I'll have what I need to get started on the weekend, but I have some obligations that may prevent that. I'll keep ya'll posted. I'll have photos when I have a link to a photo site.
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After pursuing this a little further, I realized that if I don't restuff those caps, it will bug me. Not enough to go back and re-do the work, but enough that I will wish I had done it "right"... I've found most of the caps locally, I need to find a few more, and that 6K6G tube, on line. Is 6K6GT a substitute?
I'll be starting in on the caps I have later this week. I won't be able to power up even for a basic voltage check right away because the large power supply cap is one not available local. I figure if I go slow and careful I will successfully remove and replace the caps while looking online for the other parts.
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[Image: http://osageinc.com/skyeradio/philco3840ElecB4.jpg]
Photo of the electronics. I've replaced the two largest caps, on the right.
I made a mistake. I live near Kenosha, WI. and they have a "real" electronics supply. So, I went there for replacement caps. They are far better than Radio Shack and the like, but they really have mainly low voltage / wattage etc.
I could not find all the caps I needed, but picked up what I could. I found tonight that many of them are simply too large to use for restuffing the old. As long as I need to order others, and a tube, I figured I'd replace the lot. Lesson learned.
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[Image: http://www.osageinc.com/skyeradio/philco3840Lamp.jpg]
Here's something odd. The wire connecting the dial light bulb was never soldered in. It's just hanging there. The wire looks original. The metal in the wire and the connecting lug have corrosion from the years, it all looks original; just not soldered.
I'm thinking that the original owner used to say something like "That light's acted up since the day I bought this. Just give it a 'love tap' on the side, it'll light right up".
Or something like that I'm sure
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Restuffing the paper caps, nine more to go; checking the resistors along the way etc. So, progress is being made. By the way, PuhPow's advice (in another thread) to go to that series of videos is VERY good advice. I'd never have gone to the detail of restoration that I have if not for that. Thank You! ![Icon_clap Icon_clap](https://philcoradio.com/phorum/images/smilies/icon_clap.gif) The link is
http://m.youtube.com/watch?v=IelT-Qp13po...elT-Qp13po
Now the question. There is a white block that the parts diagram calls a "compensator". I can post a photo etc, if necessary. I just am wondering, what is that? It doesn't look like it needs my attention just yet, it may when it is time to adjust and align, but not at this stage.
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