Hi all, I'm new here and this is my first restoration, so just wanted to say thanks for any help you can give!
I've been recapping this Philco 41-608 and there are a couple of items on the schematic that I can't seem to identify or figure out how to replace.
Can anyone give me any guidance on #21 and #81?
I know that #21 is in a can on top of the chassis. How does the can remove and how do you replace what's in there?
And also read another thread that mentioned that #81 should be replaced with Y- Safety caps, but I can't seem to identify what items they actually correspond to on the actual chassis?
Here's an image of the underside of my chassis. You mean the black bakelite block in the lower right of my image, removing that gets me to #81? And the screw in the lower left would detatch the can for #21?
Hello. "removing that gets me to 81"?
The capacitors are in that block and it is filled with tar. They don't look like tube type caps.
If you want you can heat the block and remove the old caps by digging or pushing out the tar after getting the block hot enough. I use an old hair dryer. will be some very small wires that come through the 3 eyelet holes and you need to cut them right where they come out of the holes Then you can install the new y2 caps in the block.
Make sure you note where the wires that solder to the top of the the block go before de-soldering..
I just remembered that Mike/morzh has a how to on this without removing the block if you want to go that route. http://philcoradio.com/phorum/showthread.php?tid=9107
(This post was last modified: 09-24-2018, 11:30 AM by KCMike.)
Well, same type used in my Zenith 9S262. The can has two welded screws that go through the chassis.
You need to cut the wires from the cap at the tar, and then, depending on whether you want to rebuild the cap or not, either replace them, making them a part of the rebuild cap, or solder them to the replacement caps.
So I've got five wires going into this can. It's possible to bypass the can by wiring a new capacitor under the chassis if I don't want to scoop out and rebuild the can? The schematic says Green to 8uf to ground. How would I go about rewiring this?
rdaskew, I edited your post so that the images would appear directly in the post. I also use dropbox to host my images. To do this in the future you simply do the following:
1) take the dropbox link: https://www.dropbox.com/s/7a7mal2sfxylwi...1.jpg?dl=0 and put it in between the following tag code with no spaces between the url and the tag code: [img][/img) (except the last parenthesis should be ] instead of ) I just used the ) so the code would be visible in this post.
2) change the part of the url "dl=0" to "raw=1" without the quotes. it will look like the following [img]https://www.dropbox.com/s/7a7mal2sfxylwir/IMG_1131.jpg?raw=1[/img) (except the last parenthesis should be ] instead of )
Yes, of course: you do not have to rebuild the cap. You might just clip the wires, leave the cap just for looks, and then find where the wires go and solder the new caps (probably axial or radial aluminum cans, or even film caps if the capacitance is in single uF) right to those places, as long as they provide good solder-post function. Many do exactly that. Of course, the places where the cap should be soldered might not prove very convenient; then using extra soldering posts and wires will help.
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.
Maybe my forthcoming comments aren't needed; but, it looks like there are 3 capacitors in the can. #21 is an 8 mfd, #21A is a 16 mfd, and #21B is a 12 mfd. There should be markings on the side of the can that identify the internal caps.
My preference has been to add the new caps under the chassis (I'm more a refurbisher than a restorer). I sometimes will add a terminal strip and mount the new capacitors to it (see photo).
Also, the #81 bakelite block has quite a few wires attached to its terminals. I've read Mike's procedure on how to do it without desoldering the wires and removing the block; but, the ones I've done like #81, I've had to desolder the wires and remove it for heating and digging out the two .01 caps that are inside. I guess I'm just not skilled enough to do it without removing the block. There is a part number on one side of the block. Could be something like 3903-DG. Use the part number and go to http://philcoradio.com/phorum/attachment.php?aid=10650 to see details of how the caps are wired in the block.
Good luck!
Larry
(This post was last modified: 09-28-2018, 01:46 PM by LarryFS.
Edit Reason: Clarify and add reference to markings on can
)
This has been really helpful. I hope this is not a stupid question to ask, but for #21, if I snip the wires at the can, how do I know which sets of wires lead to which of the three caps? How do I wire that back together? The schematic only shows Green to the 8uf to ground.
With the schematic oriented horizontally, I see #21, 8 mfd, slightly left of center. I see #21A, 16 mfd, and #21B, 12 mfd, on the right side of the schematic. 21A is shown as having a red wire from +; 21B is shown as having a blue wire from +. The blue and red wires go to the field coil. The blue wire also has a connection to pin 7 on the 7Y4 rectifier tube. The green wire goes to a junction of three resistors, items 20, 26, and 36. I've sometimes found it hard to distinguish wire colors on old radios. So Mike is correct that you need to trace the wiring to determine which wire goes to which cap.
