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Originally Posted by TheNixer
Ha ha, are we that lonely? Yikes.
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Sometimes it really seems that way...
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Originally Posted by TheNixer
I was the one who posted about the Sams Photofacts being thrown away. Hopefully that isn't the norm with all libraries.
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I hope not, I know my library has the whole set, starting somewhere at #100 or so - they didn't get them in the very beginning, so early numbers they don't have, but they have everything else. They're in big bound volumes, but with folder pockets for the TV photofacts. The copier also does 11x17, so it's real easy to make copies there.
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Originally Posted by TheNixer
I'm a bit interested in how this thread goes since I have my first vintage set in the garage.
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Yeah, I should probably come up with a "TV 101" or something... If I get the time, I can take some pictures or write up something better. But a few basic things for beginners:
Start simple. TV's are complicated - if possible start with a radio or something. You need to be pretty good at soldering.
Be careful. TV's can be dangerous. Radios too. Especially "hot chassis" sets. Learn how to properly discharge a picture tube. That thing can store a nasty jolt long after poweroff.
Take notes, go slowly. Document everything you do that you might forget - if you have to remove several parts to replace a capacitor, make notes as to what went where, make a diagram, take a digital photo, whatever. Just in case.
Keep a notebook, and write down each capacitor as you replace it, or check off the capacitors in the copy of the Photofact. This will help you be sure you got them all. Capacitors are nocturnal creatures, and sometimes like to hide in warm, dark places, like inside high voltage cages and tuner housings.
Double check your work - before you plug it in. It's easy to make a mistake, miswire something, etc. If you are up really late working on something and you're getting tired and start making stupid mistakes, go to bed. You'll just drive yourself nuts.
Don't rely on what's installed in your set. Repairs made in the past might not have been right, component values might not be correct. Look for evidence that parts were replaced in the past. See next rule.
Don't rely on the schematic. They're not always right. Sometimes there were incremental versions, production changes, slight differences in chassis, etc. See previous rule.
When in doubt, repair it the way it was (provided the work looked factory), but take note of it, so that later on, if you're having problems with that section, you can go back and try the way the schematic had it.
If the work looks crummy, or if it seems obvious that a part was replaced that was just the wrong value, then use what the schematic has. Take note of this, and the original value the part was, so that you can put it back if it doesn't work.
If you have to make any part substitutions, make note of it. It's perfectly OK in most situations to replace a .047 with a .05, and the like, since the original parts were not too tight on spec. But write down that you did that, because later, when you're looking for something, you want assurance that you're looking at the right circuit, and if you see .047 on the schematic, while looking at a .05, you might forget that you made the sub.
Capacitors are very important. Buy plenty. It's by far cheaper to order them online than it is to buy them one at a time locally. Check out justradios.com. TV's often need 1600v rated capacitors in places, and you can get those at AES - tubesandmore.com. Always buy a few more than you need of each value - either get a kit of common values from a supplier, or just round up to the next 10 or so when ordering. That way, after you get your nice TV running, and you find something else that's cool, you don't have to run out and buy caps before you can do anything with it.
Resistors are cheap. Buy plenty. A kit of common values can be had cheaply from futurlec.com. They've got all kinds of useful parts too. Another good source is jameco.com. You want 1/2 watt resistors for most things in TV's and radios. You don't need to replace all the resistors like you do with capacitors, and you can probably get away with the kit of 1/2 watt resistors that Radio Shack sells. The old resistors are somewhat reliable, and tend to be OK, but check any that you have suspicion about, or that you have to half-unsolder for something else. Old resistors tend drift upward in value, especially if they're exposed to heat, moisture, or were greater than 1meg to begin with. The new ones look a bit different, but they're electrically interchangeable.
Basic tools you need:
Screwdrivers - flat, philips, assorted sizes
Nutdrivers - 1/4", 5/16", 3/8" and 7/16" are the most common (most common being 1/4"). An adjustable wrench is nice to have too.
needle noze pliers - get a little pair of these too.
wire cutters, again, a little pair of these is handy to have too
regular pliers
soldering iron - 30 watt pencil iron for most things is good, and a 100 watt
gun for the occasional electrolytic capacitor-to-chassis job.
digital or analog multimeter
Supplies:
Assorted bits of wire - a roll of 20 gauge solid core insulated wire is indispensable, the insulation can also be stripped off and slid onto capacitor legs to prevent shorts.
Solder - get regular 60/40 lead/tin solder with rosin core. Don't use plumber's acid core solder and don't use lead free solder. The acid core eats electronics, and the lead free solder doesn't actually work.
Test gear that's handy:
A dim bulb tester. This is just a scrap of wood with a power socket and a light bulb socket mounted on it. The light bulb is put in series with the power socket. This is handy to help as a "first test" to see if the set might have a short
An isolation transformer. Finding one of these is hard for a tube TV. Arcade machines use isolation transformers for the monitor - one of these may just be beefy enough to handle the power draw of a tube TV, but likely not. I use an old medical isolation transformer I found in a scrap pile. This isn't necessary, but it's a nice safety precaution when working on hot chassis TV's. A Variac is NOT an isolation transformer, and does not provide any isolation from the mains.
A variac. I don't have one of these, but I hear they're neat. Not necessary - the dim bulb tester works the same for most purposes. But, like I said, they're neat.
I'll write more, and organize things better when I get time.
-Ian