View Full Version : Finished my Zenith porthole TV restoration


AmigaMan
12-28-2011, 04:44 PM
Hello all.

It's been a while since I got this done, and I've been enjoying it so much I'd forgotten to post about it.

It's a Zenith H2438, which I got for free a few months ago. It uses a 16GP4 CRT which was probably rebuilt a while ago based on the labels on the cone, with a lot of life left in it. I have since replaced all the capacitors, two tubes, some damaged audio wiring, and the volume control shaft which had broken off. The cabinet has been refinished, all other parts were cleaned, and the set realigned.

If you missed the original thread, and/or want to see some "before" photos, it's here:
http://videokarma.org/showthread.php?t=251501

And here it is now. This is a short demo video I made, which also includes some good photos of the restoration:
http://www.youtube.com/watch?v=lTwsk1P8f1A

Enjoy, and thank you to all of you who helped diagnose some of its issues.

–Tom

vts1134
12-28-2011, 05:14 PM
The volume of gear at your disposal gave me a nerdgasm while I was watching the first part of that youtube video.
Amazing work, the set looks great.

Sandy G
12-28-2011, 07:01 PM
The volume of gear at your disposal gave me a nerdgasm while I was watching the first part of that youtube video.
Amazing work, the set looks great.

Boy-Hidee, ain't THAT th' Truth....(grin)

ohohyodafarted
12-28-2011, 08:46 PM
Very nice restoration!! nice looking picture on that crt too.

It appears that you have a lot of high end video gear. I was just wondering why you chose to transfer the 16mm to tape instead of going directly to AVI digital. I must confess that I do not know much about commercial video tape. But I was under the impression that going directly to a digital format eliminates a factor of degredation.

Please enlighten me as to the pros and cons.

AmigaMan
12-28-2011, 09:38 PM
haha, yeah, I collect a lot more broadcast gear than I do old TVs. That was my old studio, which has since been rebuilt. My live production/edit system now fills 7 equipment racks, and most of my basement. Sort of a hobby that's gone out of control. I'll give it its own thread if anyone's interested.

Very nice restoration!! nice looking picture on that crt too.

It appears that you have a lot of high end video gear. I was just wondering why you chose to transfer the 16mm to tape instead of going directly to AVI digital. I must confess that I do not know much about commercial video tape. But I was under the impression that going directly to a digital format eliminates a factor of degredation.

Please enlighten me as to the pros and cons.

Well the simple answer is that for me, 3/4" videotape was actually easier. For anything I'm looking to archive, digital is totally the way to go. For the purposes of the demonstration though, it was the fastest way for me to get some good quality material into the set. Plus, that Elmo TRV-16 telecine I used ruins the film quality a lot more than the videotape does.

3/4" (marketed by Sony as U-Matic) is higher quality than many people think though. By the time U-Matic SP (Superior Performance) came out, it rivaled Betacam SP in quality (for composite video at least). The machines I use in my studio (Sony BVU-900 series VTRs) are the last and best U-Matic SP decks ever made, with built in digital time base correctors and noise reduction.

To get it into the TV, I used a small 3/4" player connected through a digital time base corrector (to stabilize the signal enough for the TV to sync to it) to a Betamax deck (just used as an RF modulator to channel 3). I used standard (non-SP) videotape, but for black and white they are very much the same in quality.

Still more lossy than digital, but I like to stick with analog for the fun of it.

–Tom

AmigaMan
12-28-2011, 09:43 PM
Oh, and thanks for the compliments on the set too. It was a lot of fun to work on, and I've definitely learned a lot in the process (like how well 12kV to the back of the hand wakes someone up after a late night of troubleshooting...).

ShartZenith
12-30-2011, 08:27 PM
I can only ogle and enjoy others portholes. I want one real bad but haven't found one close enough or good enough to buy, yet. But I'm determined and will. If anyone hears of one within 5 hours driving time of Kansas City, please let me know. My Predicta needs a friend.

Glenz75
01-03-2012, 05:24 PM
Good looking Zenith and a great restoration at that :yes: Love all your video gear too by way. Cheers Glen.

cwmoser
01-03-2012, 07:21 PM
Oh, and thanks for the compliments on the set too. It was a lot of fun to work on, and I've definitely learned a lot in the process (like how well 12kV to the back of the hand wakes someone up after a late night of troubleshooting...).


Certainly not wondering what it feels like:-)

Still, I have been shocked once in the past by a TV anode.
Too bad these metal CRTs did not have a rubber jacket to help prevent shocks.

Carl

ChrisW6ATV
01-04-2012, 02:52 AM
My 16" Magnavox metal-cone CRT has a flexible plastic shroud over it.

cwmoser
01-04-2012, 06:03 AM
If you have a picture of that CRT shroud, I'd like to see it.
The "Bulls Eye" tuning knob is too close to that metal CRT for me to be comfortable.

Carl

Reece
01-04-2012, 07:42 AM
Beautiful job and your film-to-video train is impressive! Now I'm off to have a big swig of Geritol! :yes:

AmigaMan
01-04-2012, 11:34 PM
If you have a picture of that CRT shroud, I'd like to see it.
The "Bulls Eye" tuning knob is too close to that metal CRT for me to be comfortable.

Carl

YES. I always have to be extra paranoid when adjusting the tuners. It's positioned so that you have to reach into the back of the cabinet (assuming you don't want to remove the chassis), and turn a knob right between the side of the cabinet and CRT (close enough to feel the charge around the tube well), and then I usually use a mirror so I can see the screen from that position.

I keep it on channel 3 though, so the fine tuning control on the front of the set is all I need to adjust usually.

Was that normal to have a commonly adjusted control in such a dangerous position like that?

cwmoser
01-05-2012, 07:24 AM
I refuse to stick my hand in the back and adjust the Bulls Eye control. I adjusted all my channels with the chassis on the workbench - and doing it that way is still too dangerous.

Not long ago, someone posted that the techs in their day stuffed their clipboard between the CRT and the Bulls Eye control. Have not tried that because I really do not like the feel of 12KV on my hand:-)

Carl

M3-SRT8
01-05-2012, 01:01 PM
Nice Resto, A.M.

Top Notch Work.