Zenith H2447R 19" Porthole TV

[Crist Rigott]

The freq. 15, 850. so that looks good.

[Kevin Kuehn]

Originally Posted by Crist Rigott

The TV is playing like there is nothing wrong. Just that noise from the FB.

Any chance the coil has gotten loose on the core? If it can move you could be hearing a harmonic of the fundamental frequency.

[Crist Rigott]

Originally Posted by Kevin Kuehn

Any chance the coil has gotten loose on the core? If it can move you could be hearing a harmonic of the fundamental frequency.

Good question. I checked and the coil is tight. After running the TV for several hours tonight, I felt the coil and it was barely above room temperature and the core was warm but not hot. I could grab it with my hand and hold it for a long time with no problem.
The squeal seems to have diminished some. Barely audible now. I'll check it in the morning and see what happens.

[Electronic M]

Some sets like to make more horizontal stage noise than others. Some of my tube sets I can't hear the whine, others when audio is muted I can tell they are on from the next room. I had a ~2007 Sharp that was the worst I've ever heard....I could hear the high pitched whine from that clear across the house I lived in back then (distances you'd have to shout at your loudest to be heard across)....That set ran for at least 5 years like that before being donated or sold in working condition.

I'd keep an eye on Horizontal cathode current and grid drive as well as boost voltage. As long as those are within tolerance may as well run it as is...It may get better. If something genuinely is wrong with the fly worst case scenario it will let go eventually. If it stays as is it is long term then it is probably just fine (perhaps a bit annoying, but fine).

[irext]

If there were any issues with FBT there would be obvious symptoms on screen. I would have a poke around while the set is running with an insulated prod (plastic pen perhaps) to see what is making the noise. It might not be the FBT at all. Gentle pressure on each component should reveal the culprit. In Aus our line frequency is 15.625 Khz and I find I now have a notch in my hearing at that frequency.

[Crist Rigott]

Originally Posted by irext

If there were any issues with FBT there would be obvious symptoms on screen. I would have a poke around while the set is running with an insulated prod (plastic pen perhaps) to see what is making the noise. It might not be the FBT at all. Gentle pressure on each component should reveal the culprit. In Aus our line frequency is 15.625 Khz and I find I now have a notch in my hearing at that frequency.

The noise has almost completely gone. Though I'm keeping an eye no ear, on it.

[Crist Rigott]

The last few days have been spent on some details.

I polished up the E-Cap cans and installed them.





I then repaired the broken shaft on the fine tuning mechanism. I found some 1/4 inch phenolic rod on eBay and bought several 6 inch pieces. The guy was from Fort Worth and they arrived the next day.

After I traced out the positions of everything I tapered the one end using my disc sander at first then my drill press to true it up. I then cut it to length and cut the groove for the keeper. To do this I used my battery drill clamped to the bench. Then turned it on and cut the groove with a hacksaw blade. Took all of 3 minutes. After cleaning up the pieces I pressed them into position. I installed the shaft and the keeper. Then restrung the dial cord.

[Crist Rigott]

I cleaned up my good picture tube I got from the ETF in October. It had some glue from duct tape in several places on the metal cone. I cleaned off the gunk, removed the labels (there were 2 of them. 1 was a Caution label and the other was also a Caution label with the CRT serial number on it), lightly sanded and cleaned off the cone. I then masked off the glass portion to the tube. One more cleaning with acetone and then 2 coats of Rust-Oleum Black BBQ paint. When dry then 2 coats of Satin Clear Enamel. This CRT looks good!

I then recreated the labels using my CAD program. Saved them as pdf's and a trip to the copy place gave me some nice red labels on light card stock. After I trimmed them to size, I used some spray contact glue and fixed them into place. Not exact duplicates but very close.

[Crist Rigott]

I need to make up and add the chassis labels tomorrow.

Here are some pics of the chassis sans labels.

[Electronic M]

Originally Posted by Crist Rigott

I cleaned up my good picture tube I got from the ETF in October. It had some glue from duct tape in several places on the metal cone. I cleaned off the gunk, removed the labels (there were 2 of them. 1 was a Caution label and the other was also a Caution label with the CRT serial number on it), lightly sanded and cleaned off the cone. I then masked off the glass portion to the tube. One more cleaning with acetone and then 2 coats of Rust-Oleum Black BBQ paint. When dry then 2 coats of Satin Clear Enamel. This CRT looks good!

I then recreated the labels using my CAD program. Saved them as pdf's and a trip to the copy place gave me some nice red labels on light card stock. After I trimmed them to size, I used some spray contact glue and fixed them into place. Not exact duplicates but very close.

Hope the HV connector gets good contact with that new paint.

I have a bakelite Admiral just like the one in the background on top of my Zenith porthole...Some of those Admirals (mine included) had one of Admiral's first LP changers.

[Electronic M]

I could be wrong, but I believe the 415 is a 44Mc IF rig, but this TV has a 21Mc IF (as do most pre-1955 sets as well as some late 50's sets)...If I'm right you will not beable to use the 415 as is to align this set (someone did find a way to heterodyne the 415 down to 21Mc with outboard parts IIRC).

[Crist Rigott]

Originally Posted by Electronic M

I could be wrong, but I believe the 415 is a 44Mc IF rig, but this TV has a 21Mc IF (as do most pre-1955 sets as well as some late 50's sets)...If I'm right you will not beable to use the 415 as is to align this set (someone did find a way to heterodyne the 415 down to 21Mc with outboard parts IIRC).

This set use a 44mc sweep.

[Kevin Kuehn]

It looks great. But why did you decide to paint the main chassis?

[Crist Rigott]

Originally Posted by Kevin Kuehn

It looks great. But why did you decide to paint the main chassis?

After I cleaned it, it just didn't look good. It had some streaks and it was "dull" looking.

[Kevin Kuehn]

Oh, OK. But you need to realize that metal plating is that way right out of the bath. Now you've made it into a work of art, which I suppose is even more interesting for most folks to enjoy today.