Admiral 14R12 Restoration

[Kevin Kuehn]

Yeah, that does look rather sun faded, but it's not to the point that the fillers are exposed. I suppose if a guy wanted a super glossy surface, one could wet sand the entire cabinet and have it clear coated with an automotive urethane. Maybe even lacquer would work, at least with lacquer you could dissolve that off if you didn't like the looks. Ive never tried it, but I'm guessing some toner lacquer would even darken the finish.

[Phil Nelson]

Remember that the glossy layer in Bakelite is thin. If you get too aggressive with abrasives, it's possible to polish all the way through it, and then you are down into the pulpy under-layer which no magic potion or process will polish to a shine.

Some Bakelite cabinets will polish up nicely, and others are just too weathered (or whatever-ed). This comes up all the time in the radio collecting world. You can spray on clear coat to make a weathered cabinet shiny. Some people also use wax, but I consider that a temporary solution.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

[Crist Rigott]

Thanks guys on the comments on the Bakelite. To get a real good shine on this one, it looks like I'll have to spray some clear lacquer on it and go from there. I did this on a Zenith table radio and it turned out real nice.

[Crist Rigott]

I replaced the door knob cap tonight. Success! I now have about 10Kv at the 2nd anode with 1 HV tester and about 13Kv with the other.

I've hooked up my pattern generator to it and I am starting to straighten out the picture.

I adjusted the ION trap for max brightness and centered the focus coil. I do have a question on the adjustment lever for the focus coil labeled Centering. I'm guessing I move the lever around to "center" the picture on the CRT. My question is there are 2 screws on each side of the Focus Coil that allows it to move up and down and from side to side. Do I loosen them to move the centering lever around and once the picture is centered I tighten those screws along with the 1 screw on the Centering lever? This is the first time I've done an Admiral and this lever is new to me.

Next problem. It seems that the H width and H lineraty adjustments do very little. There is some adjustment but the picture is past full screen. I've read the Sams on adjusting the Horizontal sweep circuit adjustments but very little happens. Is this normal? Any clue as to where to look? Remember I just replaced all the caps and resistors. I ohmed out the coils too.

Thanks.

BTW, my 210 volt line going into the fuse is now measuring 238 volts.

[bandersen]

Width and linearity controls have a very subtle effect. The drive control will have a much bigger effect

[Crist Rigott]

It's playing a DVD now and it looks pretty good. I know it can be better. I'll let it play for an hour or so to "burn it in" some.

[Crist Rigott]

Originally Posted by bandersen

Width and linearity controls have a very subtle effect. The drive control will have a much bigger effect

OK. Thanks. I'll let it finish playing then I might mess with it. I did notice that as I varied the 117vac input, the picture size changed too.

[Crist Rigott]

Today I'm going to work on the alignment. I have both Riders and Sams to go by. I'll report back on how it goes. This is pretty new to me.

[bandersen]

Originally Posted by Crist Rigott

OK. Thanks. I'll let it finish playing then I might mess with it. I did notice that as I varied the 117vac input, the picture size changed too.

Yes, that's normal. These old sets have no voltage regulation in the power supplies so things like picture size and focus will vary with the line voltage.

[Crist Rigott]

Thanks Bob.

Well I tried aligning the TV this afternoon and evening. Didn't go so good. Using my Eico 221 VTVM and RCA 167A signal generator, I adjusted the Video IF stages by adjusting A1 thru A4 for maximum value on the VTVM. I then adjusted A5,A6, and A7 for the sound alignment.

I then hooked up my Eico 369 and my BK 2010 O'scope. The waveform looked like this:



I then adjusted A1 thru A4 again to get his waveform:



Then I tried playing my DVD. The picture was awful and the sound was very fuzzy even after turning the "Fine Tuning" knob all the way to one end.

I went back and started all over again and made the adjustments and go the same results.

The waveform is centered on 25.MC where it should be on 24.3MC. I am getting about 8 or 9 MC bandwith on my sweep. The frequency for the waveform seems to be off all around. I used my digital freq. counter to set the frequency generator.

I did notice that the peaks and central valley seem awful narrow compared to the picture in Sams.

Any Ideas?

[Electronic M]

You only align radios (and other sound IFs) for max output from slugs. TVs you align the video IF for frequency response, output level be damned. There should be an alignment procedure in the philco manual if you can't undo your work consult the philco procedure. You will need both sweep and marker generators working to see the response curve and know what frequencies important features correspond to.

This is why I always advise not touch video IFs unless you really are prepared to do so. I've not done a video IF alignment yet, but have been grabbing equipment to try it. When I do I plan to do it on a set I don't care about for this exact reason.

[Crist Rigott]

Originally Posted by Electronic M

You only align radios (and other sound IFs) for max output from slugs. TVs you align the video IF for frequency response, output level be damned. There should be an alignment procedure in the philco manual if you can't undo your work consult the philco procedure. You will need both sweep and marker generators working to see the response curve and know what frequencies important features correspond to.

This is why I always advise not touch video IFs unless you really are prepared to do so. I've not done a video IF alignment yet, but have been grabbing equipment to try it. When I do I plan to do it on a set I don't care about for this exact reason.

Tom,
I was following the procedures from Sams and Riders on this Admiral TV.

The Eico 369 is a sweep/post marker generator.

I'm doing this so I can learn something about TV alignment. I knew it wouldn't be easy.

I'm posting the procedures below so we can see what I'm trying to do. Of course I'm only doing the Video IF and Sound sections for right now.

I do appreciate everybody's comments and willingness to help.

[old_coot88]

Remember that in a TV set, the IF stages are stagger-tuned rather than tuned 'on-peak' (as in a radio). Stagger tuning is for a wide bandpass which is necessary to render fine detail in the pic.

Also the signal level from the genny should be attenuated as much as possible while maintaining a stable trace.

[bandersen]

This IF design uses over coupled IF transformers rather than stagger tuned. One stage is peaked to 25.3 and the other to 23.1. That's an economical design that flattens out the response somewhat but not as good as a real stagger tuned with multiple stages each peaked to a different frequency.

Did you follow all the setup directions including replacing the converted tube (6J6) with one that has pin 1 clipped off ? As mentioned above, it's important to use as low a signal level as possible

[Crist Rigott]

Originally Posted by old_coot88

Remember that in a TV set, the IF stages are stagger-tuned rather than tuned 'on-peak' (as in a radio). Stagger tuning is for a wide bandpass which is necessary to render fine detail in the pic.

Also the signal level from the genny should be attenuated as much as possible for a stable trace.

I remembered that the Eico 369 manual talked about stagger tuned IF and sure enough the manual talks about adjusting each IF for its own frequency. I looked on Sams schematics and sure enough, there is a frequency marked by each IF coil! However there are only 2 freq. used. Yup, the 25.3 and the 23.1. Which corresponds to the Sams alignment chart.

Hmm....still puzzled on how to actually align the video IF section.