For those who don't remember or were not around to enjoy watching TV in the late 40s and the 50s please take note:
When you hook up and play your vintage TV, you may notice some things that are objectionable but are normal considering the antiquated circuitry of your vintage set. Many changes in modern TV broadcast & transmission have taken place since the early days and some affect the way an early TV will behave. Listed below are a few things you might encounter:
1) Many, if not most will lack the brightness that you enjoy on modern TV's. This is especially true on the small (3" & 7" TV's with electrostatic deflection) as they are best viewed in subdued, indirect lighting with the brightness and contrast adjusted so that the picture does not "bloom" or blur. You will have to adjust the picture and fine tuning controls when you change channels.
2) The sound may sometimes buzz and change with picture content, heavy contrasted images with a lot of text will often cause a load buzz that you cannot get rid of. This is due to the antiquated sound circuitry that early TV's had. Little effort was made to improve the sound until the late 1970's when great improvement was made. There were several different sound circuits used in the TV's made in the 1940's & '50's. Tuning in the sound (using the fine tuning) is critical on many early TV's.
3) Most TV sets built in the 1940's & '50's will not perform well on cable, most of these early sets did not have the "traps" to filter out adjacent channels that are present on cable. These adjacent channels will cause interference on the channel above or below them. For those of you who remember, in the days before cable and we had to rely on outside antennas (or "rabbit ears"). The channels were spaced, seldom would you receive adjacent channels in the same locale (channel 4 and 5 being the exception), channel 2 & 3 or 7 & 8 for example, would not be broadcast in the same reception area.
4) As the sets warm up you may have to adjust the horizontal or vertical hold controls (these controls no longer exist in modern sets). On some sets, these controls are located on the rear. It may take a while for the picture to totally fill out the screen as it's impossible to replace all the original components and some have to heat up to stabilize. I make the final adjustments on a restored set after it's been on for about 20 minutes or so.
5) You will notice some moving lines or strange "squiggling movement" at the very top of the picture (some may extend halfway down the screen) on some "network" channels. This is due to the encoding of all sorts of technical data that is encoded in what is called the "blanking interval" or "hammerhead" (this is an area of the picture scan that is not seen do to the "retrace time", or the time interval between the picture "frames"). This encoding was not done in the 40s and 50s and the sets built then did not have the appropriate circuitry to prevent this from interfering with the viewing area of the picture. This is especially annoying on Philco "Predicta's".
6) If you play your vintage TVs a lot, expect failures as it was not uncommon to have your TV serviced 3 - 5 times a year in the "old" days. You should play it occasionally (30 minutes or so) at least once a month. I would not recommend playing it for hours on end like you would a modern TV, this is especially true on sets with limited space for air circulation such as the Philco Predicta and the small compact sets. Back in the late 40's & 50's, there was an army of TV service men who kept those TV's going. Although these old relics may be properly restored, many of the engineering problems that hounded those TV's when they were new are still with them today.
7) Vintage TV's that have been properly restored will work quite well from a VCR or DVD player. Be aware that many DVD's and tapes are encoded with anti copying signals. Such tapes & DVD's may cause some viewing problems. To connect a VCR to your TV, a 300 ohm matching transformer is required from the VCR's cable to the antenna input of the TV. To connect a DVD player (which has no RF output or cable connector), an RF modulator is requited to produce channel 3 or 4. These can be purchased for about $20.00 from "Target" or other electronics retailers.