Need help identifing and fixing Majestic 17" tv

[Eric H]

The blown part is a ceramic disc capacitor, seldom bad so I don't know what happened to yours.

Is it connected to the antenna terminals? Perhaps it was hit by lightning,

[Kawooa]

Originally Posted by stromberg67

Just looked up the SAMS on the Early Television Org. Website. It's available for download as a PDF. Nice. simple power supply, and good, straightforward circuits, unlike that accursed Emerson I'm now fighting with (model 698-B, with a partially "upside-down" power supply. You will have a much easier time with that nice Majestic!
Kevin

Upside down?
Yea. Looking at the underside of the chassis it looks easy. Analog tv's are simple from what I've seen. Nice and easy is good. But I would love to have this working to watch tv with if I can get a digital converter to work or use a 75ohm coax to 300ohm adaptor. I searched that up and I wonder if it will work.

[Kawooa]

Originally Posted by Eric H

The blown part is a ceramic disc capacitor, seldom bad so I don't know what happened to yours.

Is it connected to the antenna terminals? Perhaps it was hit by lightning,

The part I don't think was ever connected to an antenna. The blown parts goes from the photo motor outlet to ground. I would assume it also has another on the other power line side to ground from what I saw in the schematic.

[DavGoodlin]

This interesting set has a power transformer, so each side of the 120 volt mains should be connected to chassis ground via a Y2 safety capacitor, about .05 mf.
Check the Justradios.com website about the safety caps there is a good tutorial on them.
If you get just the power supply recapped, then you can power it up slowly to check progress as you replace all the paper caps.

[Kawooa]

Originally Posted by DavGoodlin

This interesting set has a power transformer, so each side of the 120 volt mains should be connected to chassis ground via a Y2 safety capacitor, about .05 mf.
Check the Justradios.com website about the safety caps there is a good tutorial on them.
If you get just the power supply recapped, then you can power it up slowly to check progress as you replace all the paper caps.

I think I can understand that now. I have read the justradios Pages many times before and after I first started trying to repair electronics. The articles are really good. And I think I will add at least two y2 safety caps. Since those can be used as both y and x then I would have one filtering the line in and one from line to ground.

When powering on as replacing parts what would you check? And like how long would it take?

[Kawooa]

I found a BK crt model 400 tester online. Is that tester able to test the tube in this set? I want to see how the tube is. That way I can determine if I will repair the set or do other things with it. I don't know what tube is in the set right now. I never tried looking for a model number.

[Eric H]

That tester should test the CRT, it about as old as the set itself so it may need recapped too.

[Kawooa]

The picture tube appers to be a 17bp4 from the internal tube chart sticker.

[Kawooa]

Something I had been forgetting to ask about is this weird silver colored open circle on the top inside of the cabinet. What is it? If I remember right I took my multimeter and measured about 3ish ohms on the two terminals. It looks kinda like a internal antenna.

[dieseljeep]

Originally Posted by Kawooa

Something I had been forgetting to ask about is this weird silver colored open circle on the top inside of the cabinet. What is it? If I remember right I took my multimeter and measured about 3ish ohms on the two terminals. It looks kinda like a internal antenna.

That's exactly what it is. Many sets came with them, very few were used.

[Kawooa]

I have purchased the bk crt 400, a variac with a 1.4kva rating and a isolated transformer of 250w. Hope that can let me safely test my vintage electronics without "shocking" results.

[Electronic M]

When it comes to variacs and isolation transformers one thing to keep in mind is the failure mode is overheat....If you need to run a set with a higher power consumption than they are rated for it is perfectly safe to do so for several minutes provided you monitor temperature and avoid overheat.

[Kawooa]

Originally Posted by Electronic M

When it comes to variacs and isolation transformers one thing to keep in mind is the failure mode is overheat....If you need to run a set with a higher power consumption than they are rated for it is perfectly safe to do so for several minutes provided you monitor temperature and avoid overheat.

Not sure if that'll affect me right now. I got a variac with what seems to be a 1000w rating. It's 1.4kva and that factors over somehow. I forget which math brain melter formula it is(for me at least, math is not a favorite of mine.) As for the isolated transformer that's got a 250w rating. It's a tripplite model whatever. Seems really nice and sturdy. I have always enjoyed their products not being plastic crap but instead being nice, strong metal boxes. The tv has a sticker stating 170ish watts. Should be safe there.

I may end up building a dim bulb tester to go with this as well. I saw it on antiqueradio.org. The variac is plugged into the wall to meter voltage if the isolated transformer can handle that. Otherwise it's the other way around. Then the dim bulb tester is plugged in to control current. Then my watt meter is plugged in to measure volts, amps and of course, watts. Then the poor, doomed test subject. Err I mean TV set.

Next on my list. Finish my zenith and Meissner projects then start this. What should I begin with? I saw on antiqueradio.org this guy would start with power supply then test set if he was brave enough. Should I try that route?

[Electronic M]

Some sets are worth a variac power up with no parts replacement....That majestic probably ain't one. Mine had a blown 5U4 (white gether, and glass came off the base when I tried to unplug), some of the lytics were shot on mine others were marginal. Every paper cap including the square ones that look like micas, but aren't tested leaky, many were practically dead shorts in my majestic. Until you have lytics and most of the papers replaced don't expect much from it.

[Kawooa]

Originally Posted by Electronic M

Some sets are worth a variac power up with no parts replacement....That majestic probably ain't one. Mine had a blown 5U4 (white gether, and glass came off the base when I tried to unplug), some of the lytics were shot on mine others were marginal. Every paper cap including the square ones that look like micas, but aren't tested leaky, many were practically dead shorts in my majestic. Until you have lytics and most of the papers replaced don't expect much from it.

Ok thanks. I was just wanting to see what it does since the previous owner tried a power test and it had a buzzing and flickers of light. I wanted to see what it do for that buzzing. If I knew the problems better then they could be fixed easier.