I have been re-capping my Admiral 20A12 & wanted to check to see if I could get a picture. I hooked up a VCR but could not get any picture or sound, just snow. Is the old channel 3 different than the modern channel 3? Or do I have a tuner problem?
Thanks

You have a tuner problem. Using a VCR to operate your vintage set is the best approach, since most of them don't work well with adjacent channels from cable systems.

If you have snow on the screen, chances are that the IF section is working. Check your local oscillator frequency.

It appears I spoke too soon about having snow. After changing more capaciters what I thought was snow cleared up! This is my first TV restoration - I have been doing radios for a while. Bad IF section?

There is no difference between "old" and "new" Channel 3. I would disagree about using a VCR to test out an older TV. I know it may seen hard to believe, but they still do broadcast things over-the-air! (I must be the only guy on earth without cable/dish?) In other words, just try some good old fashioned rabbit ears. You can get a set for less than $5 at K-MartWalTarget.

Unless you live waaaay out in the hills, You should get a more than enough signal quality for B&W. In urban areas, most sets will pull in some kind of lousy signal even without any antenna. The reason I'd recommend against a VCR for "testing" is because it can only complicate matters. For example, is the VCR set to use RCA outputs instead of 75 Ohm? Is there a problem with the VCR? Who knows? Best to keep it simple until you know it works.

Before you condemn the IF section; are you getting any type of sound? Even "rushing" white noise? No video at all, or just snow? If you get any of this snow/noise, the problem should lie before the IF stage, perhaps a weak tuner tube.

I get no sound & the screen is completely one shade of medium gray ( Light or dark depending on brightness adjustment)
Unfortunately the lowest numbered local channel is 16 - My tuner only goes to 13.
Is the IF section a big problem to fix?

No channels below 16? Wow.

I'm not really that familiar with Philco sets, but I will say this...

A lot of TV restorers like to dive into projects by recapping everything in sight. While I do understand the need to replace the caps (eventually) I've yet to meet the "reasonable" condition B&W set that couldn't produce a picture with original caps. Recapping without any poking around seems a bit scatter-gun to me.

You most likely have some weak IF tubes, or a tuner RF amp that is completely shot. No harm in running the set, on any channel without a VCR, and tapping some of the tubes in the tuner/IF section with the end of a pencil or something. If you get any kind of snow/static, you're getting closer to the problem area. Rocking the tuner knob wouldn't hurt either. (Dirty contacts)

The next step would be some tube substitution in these areas (if you've got some extras). If your set is like most Zeniths, and uses a few of the same IF tubes, try switching them and see if it has an effect. If yes, you've got a bad tube.

Most of the time I have seen this kind of problem it has been dirty contacts in the tuner. In these tough cases it is not enough to just spray the contact cleaner in and turn the knob. You have to use a q-tip or lint free cloth saturated in contact cleaner (Deoxit, etc.), remove the tuner cover, and clean all the little buttons on the channel strips. The silver plating can get really tarnished over time.

Although, as Carmine said, a set will usually work after a fashion on old caps, I always replace all paper caps (usually used in pre-1963 sets) before trying to find a problem. Paper caps are unreliable and just continue to degrade, or can be thermally intermittent, making troubleshooting on such a set difficult. These caps can have enough leakage to short out and destroy resistors or coils.

Also, unless you have an old-time UHF convertor, a VCR will be necessary to actually get all of the TV channels (or any of them, in this particular case).

Thanks for the help. I cleaned all of the tuner contacts, it was hard to believe how dirty these were. I substituded some tubes & found a bad one on the tuner section. I now have snow on the channels, it was previously gray on the channels - same as in between channels. I still can not tune a chennel but I'm getting closer. Removing the tubes next to the IF coil makes no difference on the screen. I'm thinking of checking for open IF coil but this would probably require de-soldering & disconnecting and is in a difficult location. Any thoughts?
Thanks

Most likely not an open IF coil unless there was some kind of physical damage or catastrophic failure of something else. You can test for continuity without unsoldering the coil. Best bet is to signal trace starting at the picture tube and working your way back. Old television repair books have some very useful tips. If you don't have a signal generator or scope one dirty method is to attach one end of a .1 630 volt cap to one leg of the heater string and poke along the circuit with the other end. It will introduce a 60hz hum into the circuit you can see on the screen. When you get past the defective component you won't see the hum bars on the screen.

If you've got snow, (with white noise sound?) I'd say that receiving a signal should be possible. Have you tried the VCR yet? How's the wiring between the antenna lugs and tuner?

As was stated earlier, it's unlikely that you'd have any open coils unless they are physically damaged.