Zenith H2447R 19" Porthole TV

[wa2ise]

Sometimes I misread the thread titles, here I first misread "porthole" as "portable". Wonder if Zenith ever made a portable porthole.
Like those GE locomotive like portables, except with the entire round CRT exposed.

[Electronic M]

Originally Posted by wa2ise

Sometimes I misread the thread titles, here I first misread "porthole" as "portable". Wonder if Zenith ever made a portable porthole.
Like those GE locomotive like portables, except with the entire round CRT exposed.

There was a 12" table set IIRC 1950 model year in a leatherette cabinet...Not sure if they had the stones to add a handle and call it portable.

IIRC MacDonald had the engineers adapt a table model porthole chassis into the back seat of his limo so he could watch TV on the go....Some electronics mag of the day had a write up on it. I bet he let them do the article as a way to put out feelers to see if there would be a car-tv market.

[Crist Rigott]

I started on the main chassis and the E-Caps first. I removed C1 and C3. When removing them, I broke off some of the twisty mounting tabs. This is usually the case. Once is a great while, I'm able to remove a can without breaking them off. These were really twisted!

I'll go into detail on how I re-stuff a E-Cap. Both of these caps are 4 sectioned caps. A while ago I won an auction that had like 25 E-Caps that were 4 sections with the sole purpose of using them as "donor" bases.

Here are the 2 caps and their donors.



I cut the originals as close to the base as I can with my band saw. I use a piece of 1/32 plywood as a shim to prop up the can because the base is larger in diameter. As I cut with the band saw, sometimes I'll rotate the cap some just to help keep the cut straight.



Here are the results of cutting the originals. All I'm interested in are the "cans". The bases are no good to me.
After removing the cardboard covers using my heat gun, I then cut the bases off the donor caps. This iime close but not so close to the base as with the originals. Here are the results:





Notice how much fuller the original cans are compared to the donors. Here is a picture of the original cans and the cleaned up donor bases. I clean up the bases using a brass brush and then drill a 5/32 hole in the middle. These holes were offset slightly to avoid drilling through the terminal symbols. I'll clean out the cans using a heat gun to remove the guts, and some steel wire brushes, acetone, paper towels, and Q-Tips to clean the cans.



The donor bases are about 1/8 inch taller than the originals. Not a problem on this chassis.



Next thing to do is make up some sleeves from 1 inch PVC pipe I got at Home Depot. I forgot the exact size but maybe it's 1 1/2 inch pipe. It is the thin walled stuff. The first thing I do is true up the end using my disc sander and 90 degree guide. When truing it up, I rotate the pipe about 1/2 to 3/4 turns.



I then mark the trued up end with an arrow. This end will be glued down against the base.



I then use my 1 inch wide ruler to make a mark 1 inch up from the trued end. I go all around the pipe.





I then cut off the pipe on the line just made. I then clean up the cut end with the disc sander. I then repeat the whole process for the other sleeve starting with truing up one end.
Once I have the sleeves cut out I then de-burr them using my hobby knife and #11 blade, and some 80 grit sandpaper.



I then use 15 minute epoxy and apply the epoxy on the trued up end being careful not to get any epoxy on the outside of the sleeve. Then the sleeve is inserted down onto the base. I then clean off any and all epoxy that has gotten onto the outside of the sleeve especially down near the base. Any epoxy here will prevent a good seam when the can is put into place.

[WISCOJIM]

Originally Posted by Electronic M

IIRC MacDonald had the engineers adapt a table model porthole chassis into the back seat of his limo so he could watch TV on the go....Some electronics mag of the day had a write up on it. I bet he let them do the article as a way to put out feelers to see if there would be a car-tv market.

Different MacDonald?

https://books.google.com/books?id=NN...r%20tv&f=false

.

[Electronic M]

Originally Posted by WISCOJIM

Different MacDonald?

https://books.google.com/books?id=NN...r%20tv&f=false

.

That is the article I remember.

[WISCOJIM]

Originally Posted by Electronic M

That is the article I remember.

I don't think this William M. MacDonald, Jr. had anything to do with Zenith Corp.

.

[Crist Rigott]

OK, back on topic.
Here is what I did to make recapping a whole lot easier. I took 2 pieces of hardwood about 5/8 by 3/4 by 12 and bolted the to the side of the chassis. This allows a comfortable tilt while I'm working.

[Crist Rigott]

OK, lets stuff C3. This E-Cap has 4 sections to it. For section A I'm using a 22uf 500V, section B is a 39uf 350V, section C is a 100uf 100V, and section D is a 82uf 100V cap. All are 105C Nichicons.

First thing I do is the see how well they fit into the PVC sleeve. Typically 4 will fit nicely. This gives me an idea on how to hot glue them together. I usually start with the 2 largest caps and glue them together with the negative terminals close to each other. Then the next largest and finally the smallest cap. I align the negative end of the caps to be equal. I then trim off the positive lead of each cap to about 1/4 inch in length. I then fold over the negative leads with my round nosed pliers toward the center and trim them off.



I use solid 22awg 600V wire for the new leads. I use black for the common and then loop it around the negative leads and solder them all together.



I then use the coil method to solder the new wires on each cap. For section A I use brown, section B is red, and so on.



I then fold over each wire toward the middle and then fold it again to have all the wires coming out together. Again, I use round nosed pliers for this. I then secure the wires together with some lacing cord to secure them.



I then insert the wires through the 5/32 hole I drilled into the base. I then place a mark on the wires where I want to strip them. I leave the common wire stripped a little longer like about 1/4 inch. I then trim off the excess wire length.



Next I put a large bead of hot glue on the lacing cord knot and inset the assembly into base. I then use hot glue around the inside of the sleeve to attach the caps to the sleeve.



I then terminate the wires on the base terminals. I typically will wrap the wires below the hole in the terminals. This leaves as much room for wires in the hole as possible. On this cap the half moon is section A, square is section B, triangle is section C, and no mark is section D. I'll terminate the common wire after the base is inserted into the chassis.





The new base is installed into the chassis, the common wire terminated and the soldered onto the chassis. Notice I went easy on the twisty things. The next guy will appreciate that. Though thinking about it, he'll never have to remove the base. Just unsolder the wires and pop out the caps!