Philco Model 41-296X with 41-285 modified chassis
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jjbuzard Wrote: To simplify the replacement process while I have one end of a wire undone that shares a terminal with a capacitor, I pull the wire out of the chassis, leaving the other end attached, straighten the wire out and gently twist the rubber insulation, if it doesn't fall apart, I continue to twist and gently pull until the rubber insulation starts to pull off the wire, then I pull the rubber insulation all the way off, then I slip a new piece of wire insulation from an OLD underground phone cable (about 18 gage wire) that I have laying around (all colors available) I have had this since I was 10 years old (it finally came in handy) To get the vinyl insulation off the original wire, I soak it in very hot water, it slips off easily after expanding, and then I slip it on the wire in the chassis, I then reroute the wire and resolder the loose end along with the capacitor. Do you foresee any thing wrong with this method :
It sounds like you are doing very well with your repair. Yes, it is a very good idea to only replace one capacitor at a time; that reduces the chances of miswiring a component.
You are doing basically what I do with these 1939-1942 Philcos. The only difference is, I use new 3/16" heat shrink tubing which is available in several colors. I remove one end of the old wire, remove the old, crumbling rubber insulation, then cut a new piece of heat shrink tubing to fit which I then go ahead and use heat on to shrink before installing. Slip it on over the wire, then reconnect the loose end of the wire. The end result looks just like the old rubber insulation, only it's new.
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Ron Ramirez
Ferdinand IN
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I originally was going to use heat shrink tube so I went to Radio Shack (my only option here locally) and they were out, so I wanted to get started so I tried to come up with an alternative, first I used Door Bell wire, cut it to length and pull the insulation off and with one end of a wire undone in the chassis, slide the new insulation on, great except it only comes in two colors, white and red, so I tried to think of something else and I remembered the underground phone cable end I had left, back in the 50's they were laying one of the first underground cables in our area, from Rockford to Peoria, it went right by the farm I grew up on, every half mile they would have to splice two cables together, to do this they would cut 1 to 2 foot off each cable and make their splices, they would throw away the cut offs and I gathered up several, I was about 10 at the time and used them for crafts, etc. Fortunately I had one left which I had saved all these years. (it finally came in handy) By warming the wire up in hot water I was able to pull the vinyl insulation off, and as this wire is 18 gage the cover slips right on the 20 gage in this chassis. Works slick and there are about 100 wires in each cable end so I have plenty and plenty of colors. The other plus is I don't have to use the heat gun to shrink the heat shrink tube.
The other point I was making was, when I started I looked at all of those caps and rubber wires and was overwhelmed, after a day or so I went back to it and decided I would concentrate on 2 caps and the associated rubber wire, if I only thought about those 2, I wasn't overwhelmed and when those two were done I picked out two more and so on and it seemed easy then, so I am proceeding.
Also in checking out the Philco Phorum I discovered that I should be actually posting this in the "Philco Electronic Restoration" sorry, should I move to there?
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jjbuzard Wrote:Also in checking out the Philco Phorum I discovered that I should be actually posting this in the "Philco Electronic Restoration" sorry, should I move to there?
![Icon_redface Icon_redface](https://philcoradio.com/phorum/images/smilies/icon_redface.gif)
No, don't worry, I will move this entire thread there. I should have done so already. I must be getting old.
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Ron Ramirez
Ferdinand IN
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Thanks for understanding a Rookie, by the way I was browsing the rest of the Phorum and saw you wedding announcement, Congrats and thanks for the picture, it helps to put a face to a name and the one with your signature made you look old like me, ![Icon_lol Icon_lol](https://philcoradio.com/phorum/images/smilies/icon_lol.gif) now I know you are just a kid
Got both of my new transformers yesterday, (both are Hammond, a 125 series for the Audio Output coil & a 270DAX for the main transformer) now I have to figure out which wire is which as they don't color match with the old ones, ( I will check OHMs to accomplish this) and as they are both larger than the original ones, I assume (hate that word) I will have to mount them both on top of the chassis, I believe you said something in an earlier post that as the Audio Output coil was mounted under the chassis it didn't fare so well, so moving it to the top is a good thing ![Icon_confused Icon_confused](https://philcoradio.com/phorum/images/smilies/icon_confused.gif) :
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Well, thanks, but I'm no kid anymore...I will be 50 come April...
The picture in the avatar at right is James M. Skinner, who was the President of Philco during their glory years (1930 to 1939).
You should mount the new audio output transformer in the same place as the original was mounted. See, you will not be storing your radio in a barn or in any rodent-infested areas, so the new one should be just fine if it is installed where the original was. It is best to locate parts where they were originally to avoid problems.
I see you bought a vertical mounting power transformer to replace your original - a 270DAZ (horizontal mounting, like the original) would have been a better choice, but you can still use the 270DAX. You may have to modify the hole somewhat to permit the wires to pass through. You do not want the wires rubbing against the chassis!
Both transformers should have a paper showing which wires are for what winding. Study these carefully. If for some reason you do not have these diagrams, you can see diagrams for both on the Radio Daze website.
http://www.radiodaze.com/
Click Components, then Transformers & Inductors - Hammond Mfg., then Classic Plate & Filament Power Transformers (Hammond's 263 - 282 Series) for the power transformer; Universal Push-Pull Tube Output Transformers (Hammond's 125 A-E Series) for the audio output transformer.
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Ron Ramirez
Ferdinand IN
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The 125 series coil is about 2 1/2 times larger than the original audio output coil, that is why I thought I should mount it on top, but if I turn it sideways 90 degrees to the original it should fit. I relied on Radio Daze for the transformer and coil selection. I can probabily use a rotary grinder to open up the opening for the transformer and mount it flat, protecting all fragile stuff from flying metal shavings.
The audio output coil only has 3 wires compared to the original, you said "It will have three thick cloth-covered wires coming from it, another smaller wire, and a wire that you may not notice that is soldered to the frame. The smaller wire and the wire soldered to the frame are the leads for the secondary winding of the output transformer. The three thicker wires are the primary leads - one is a center tap."
I don't see "another smaller wire, and a wire that you may not notice that is soldered to the frame." on the replacement coil. it also has 6 empty terminals.
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You say you bought a 125 series audio output transformer, exactly which one did you get?
Regardless, drill out the two rivets that hold the original audio output transformer in place, and mount the new one where the old one was.
Correct, the new one has three wires for the primary and six small terminals which are for the secondary. These terminals have numbers under each, correct? (1 through 6) Assuming you do not have the hookup diagrams which should have come with the transformers, I'm going to save you a bit of trouble on the audio output.
Before you remove the old audio output transformer, look carefully at it. If you look closely, you will see one bare wire going to a particular terminal on a terminal strip close to the transformer. This is important - it is one of the output leads. The other lead is grounded (soldered) to the frame of the transformer. Now with the new one, we are not going to solder any wires to the transformer frame. Instead, look carefully at that terminal strip closest to the audio output transformer. Look for a lug riveted to the chassis on that strip that also has a terminal sticking up. This will be your new grounding point.
You will have two choices to try for your speaker output. First, try connecting the speaker output to terminals 2 and 4. Terminal 4 should be connected to ground.
If this does not sound to your liking, remove the ground from terminal 4, remove the connections from terminals 2 and 4 and use terminals 3 and 5, with terminal 5 grounded.
(And by the way, anyone else reading this is welcome to chime in... or has everyone else already gone off on their Christmas vacations?)
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Ron Ramirez
Ferdinand IN
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Ron Ramirez Wrote:Now go and doublecheck that field coil resistance. Measure it while the speaker connector is still disconnected. Remember, the field coil is the large coil in the back of the speaker, and should read in the neighborhood of 1100 ohms. (There are four pins on that speaker connector. You should read around 1100 ohms between the two inner pins, and only a few ohms across the two outer pins. That is the voice coil winding.) The small transformer under the chassis that is somewhat close to the power transformer is the audio output transformer, so make sure you are measuring the right thing.
Ron--thank you for posting that. I kept meaning to ask how I should check my assortment of various speakers I have for my 40-190. Both of my speakers' field coils tested out at about 550 ohms BUT BEFORE I freak, I also have to say that my old Sperry analog handheld VOM suddenly won't calibrate anymore. I am going to have to upgrade... it isn't like this one hasn't been dropped a bunch of times over the years.
The fact that BOTH of my speakers tested out the same (one also has an open voice coil; I can see the problem but have no idea how to reconnect a wire that fine) on the field coil suggests to me that, rather than identical faults, I have a crappy VOM. I think I'll use this as a convenient excuse to upgrade. ![Icon_lol Icon_lol](https://philcoradio.com/phorum/images/smilies/icon_lol.gif) (The other theory is to pick up a packet of mixed resistors at Rat Shack if they still have any and find out what 1100 ohms should look like on my meter, just as a quick-and-dirty. But a new digital VOM is definitely on my horizon.)
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The coil that Radio Daze sent me says 125E on top it is much larger than the original, the original coil rivet spacing is 2 3/8" this one is 3 1/8" and 1 1/2 time taller ![Icon_confused Icon_confused](https://philcoradio.com/phorum/images/smilies/icon_confused.gif) : Yes it has 6 numbered terminals plus the blue, red and brown wires on the opposite side.
On the original yes one is soldered to the frame and one is to the terminal strip nearest to the coil, it has a rubber sleeve on it.
But here is where you lose me
Quote: You will have two choices to try for your speaker output. First, try connecting the speaker output to terminals 2 and 4. Terminal 4 should be connected to ground.
Are you telling me to connect coil lug 4 to a ground point and coil lug 2 to the terminal strip where one of the speaker wires is connected ![Icon_confused Icon_confused](https://philcoradio.com/phorum/images/smilies/icon_confused.gif) :
Quote:If this does not sound to your liking
I really don't understand that, what do you mean If this does not SOUND to my liking?
Sorry to be so thick, but I want to understand this and not fry something else.
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jjbuzard Wrote:Are you telling me to connect coil lug 4 to a ground point and coil lug 2 to the terminal strip where one of the speaker wires is connected :
That is correct.
Quote:I really don't understand that, what do you mean If this does not SOUND to my liking?
Sorry to be so thick, but I want to understand this and not fry something else.
I mean that, when you get the radio going again, if you are not entirely pleased with how the radio sounds, then try the other lugs I mentioned.
If anyone needs me, I'll be over in Old Ron's (that's me) Bar & Grill...buying a virtual round for the house.
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Ron Ramirez
Ferdinand IN
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Ron,
I am down to 3 Capacitors to replace and just a few rubber wires, have used your method of heat shrink on a couple, the rest I am using my method of sliding on a new cover, going well. HOWEVER, I am worried about acouple of wires on the band selecor switch, I see where some people have broken this switch while changing wires, what is the complication here? I have one wire that HAS to be replaced that is entirely inside the switch mechanism, a little short one, how much heat can this band selector take when soldering ![Icon_confused Icon_confused](https://philcoradio.com/phorum/images/smilies/icon_confused.gif) :
Jim B
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Jim, it is those wires going to the band switch that usually have the semi-deteriorated rubber insulation stuck to them. Pull a little too hard on them, and SNAP - you break the band switch. I've done it more than once; this is the reason why I hate working on these Philco chassis (41-250/255/280/285/287/290/296).
Try your 40 watt pencil to remove one end of each of those wires (one at a time, of course). And then, without messing with the old rubber insulation, slip a piece of heat shrink tubing that you have not shrunken over each one. Reconnect to the same spot it was connected to, do the other wire(s) going to the band switch in the same manner, and forget it. That way you won't be taking a chance on breaking a band switch wafer.
I have a 41-611 radio/phonograph console, a similar chassis but with four bandswitch wafers instead of three as in your set. I tried to sell the set as is when I moved...no takers. So, since it has a Beam of LIght changer in it, I am going to restore and keep it. Don't know when I will work on that chassis though...I dread it.
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Ron Ramirez
Ferdinand IN
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My plan right now is on that little (less than 1 inch long) wire inside the band selector is to clip both ends off and solder in a new wire and use as little heat as possible and thereby avoid pulling or twisting that wire trying to unwrap the wires while keeping the solder hot and maybe breaking a terminal, is this wise ![Icon_confused Icon_confused](https://philcoradio.com/phorum/images/smilies/icon_confused.gif) :
Or should I unwrap the wire from the terminal ![Icon_confused Icon_confused](https://philcoradio.com/phorum/images/smilies/icon_confused.gif) :
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Your plan makes sense to me...
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Ron Ramirez
Ferdinand IN
Posts: 46
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Joined: Nov 2009
I installed the 125E Hammond Coil (for the Audio Output Coil) I got from Radio Daze, the schematic for the 41-285 chassis calls for 190 OHMs across the White to Black & White and 170 OHMs across the Black to Black & White, the readings I get are about 75 OHMs across both, about half what they should be I double checked the diagram that came with this coil and I do have it wired right ![Icon_confused Icon_confused](https://philcoradio.com/phorum/images/smilies/icon_confused.gif) : I haven't attached the secondary windings yet.
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