yeah.....Candohms. They are called so for a reason.
And rebuilding them is a pain. I have rebuilt one for my 7G605 TO (it was fine as the resistor but leaked to the case resulting in loud hum), and even though I was successful, it is putting bulky modern types into the case, and yours probably is the "flat" type with no bulky case like mine was.
Unless by rebuilding you mean using some solder posts or barrier block strips and assembling the resistors there (I did this on my 9-S-262).
In any case, wish you a fast recovery after that chemo session and overall recovery as well. I hope by now your docs could see some results of 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.
HEY!
I have one of those! In about 40 pieces,
Now I know what those little clips were for..
I did not know it was a battery set when I bought it.. Silly me...
Looks great thus far Ron.
And here is how the underside of the chassis looks at present:
The resuffed electrolytics are installed and (mostly) hooked up. I say "mostly" because one wire from the combination 10 uF / 2 uF can connects to the Candohm, and I have yet to replace the Candohm with new resistors, solder terminals and a strip of aluminum. That is a job I hope to accomplish this weekend, along with replacing a wire coming out of the top of one of the IF transformers and connecting to the grid cap of the 6K7G IF tube. That, along with a replacement power cord, some misc. odds and ends, and reassembly of the dial with new dial lamps, and this Zenith should soon be ready to try out!
I decided to order a new dial glass gasket from Mark Palmquist, since the original is very fragile and has already broken in a few places. That should be here by the weekend, just in time to reassemble the dial.
Finally, for those of you who like to follow the bouncing resistor symbol, here is the schematic for this Zenith, along with voltages and alignment info:
Mike - thanks. Actually I used 10 gauge solid, insulated. I drilled the old, hardened rubber insulator just enough for the wire to fit through. 14 gauge is too small and would be way too loose. I have found that 12 gauge is also a bit loose. 10 gauge seems to work just fine, and I bought a roll of it just for restuffing wet electrolytics.
Looking good Ron! I have a Zenith 288 I need to restore and I already bought some Solen caps for it. Your rebuilt capacitor can looks great. Looking forward to your candohm rebuild.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
is this hotglue I see you put on top the Solen cap?
If yes, when I pot film caps (they are plastic film and I do not know how they react to hot glue if applied straight on) I put a cut to size fitting piece of thin cardboard on top. This will stabilize things without directly heating the cap.
It's the same as when restuffing tubulars with film caps, when we put some wad material before potting the leads (depending on the space left I either roll a strip into a spiral and then put in if there is space, or cut a circle, poke a hole and slide it down the wire if there is little space left). This way even i some hot glue makes it down to teh cap, it is little and will cool fast without potentially harming the cap inside.
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.
Mike, I have yet to have any issues with hot glue on film capacitors...although perhaps I should be more careful and do as you suggest. I do know better than to get hot glue on electrolytics. Don't ask how I know.
The top of this assembly is a positive lead, as is the bottom - the middle is negative as the caps are connected in parallel to add up to 16.4 uF. A Solen 18 uF 630V cap is too large to fit in these aluminum can electrolytics. So I wanted to make sure the top lead did not make contact with the top of the aluminum can. The hot glue serves as an insulator (along with heat shrink tubing) to accomplish that.
>>>The hot glue serves as an insulator (along with heat shrink tubing) to accomplish that.
A noble cause indeed
Here's how I see it:
1. Cut a circular piece of dense paper (backing from a sticky notepad etc) diameter of the can. Should fit in the can snug and definitely be larger than the cap itself.
2. Make a hole in it for the top cap's conductor to go through before you bend it and route it down the can to the positive pin. You could cut a little notch in the cardboard circle for that wire to easily go where it should without having to bend the cardboard. Make the conductor protrude a bit through the center hole in the washer so the hot glue catches on it and thus stabilizes the cap a bit. It is not the kind of assembly that is subject to vibration so you do not have to be overzealous with the stabilizing. Just so it doesn't bend due to gravity back and forth.
3. After assembling everything put hot glue on top.
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.
(This post was last modified: 11-14-2019, 08:55 PM by morzh.)
Four tube shields arrived today from a friend in Lexington. They are now installed on the chassis.
I also took the time to remove the two rivets holding the Candohm in place. Most of the wires are still attached to it. It has so many terminals that I intentionally left it this way to (hopefully) make it easier to know which wire goes where on the new assembly and to reduce the possibility of errors in wiring up the new assembly.
Tomorrow afternoon...hopefully...the installation of new resistors to replace the Candohm begins.
One more thing. I did measure the (formerly) wet electrolytic after restuffing was complete with the capacitance meter function on my DMM. 16.4 uF, just as it was supposed to be. So the hot glue must not have hurt it.
However, Mike, I think I will go with your suggestion henceforth for that extra level of safety.
Here's what I started with - remember, in a previous post I said that I had removed the rivets holding this in place on the back of the chassis:
There was one terminal which was grounded to the chassis, as you can see where the arrow is pointing to the solder blob above. The trouble is, the solder did not stick to the chassis as the Candohm came off when I removed the rivets, and the solder blob did not hold the Candohm in place.
I carefully measured the total length of the Candohm - 8-1/4 inches. I then cut a piece of flat aluminum to this length.
Next, I laid out the resistors which would be used to replace Candohm sections, in order to roughly determine where to place terminal strips.
Having determined that, I then marked spots where I would need to drill holes.
Did you use a 12 or 14 gauge wire to run through the capacitor?
