Hallicrafters Model T-67 Television (1948)

This lovely 10-inch set is my second Hallicrafters television. Although it is the same age as my Hallicrafters 505, this one represents a definite step up in quality. It also was easier to restore.

Description

The Hallicrafters T-67 is typical of "doghouse" shaped 10-inch televisions of the late 1940s and early 1950s. Designed to sit on a tabletop, it measures about 18 inches high, 16 inches wide, and 20 inches deep. It is also very heavy, thanks to its robust transformer power supply and dual chassis.

The first photo shows the restored television.

Priced at $279.50, this TV cost $80 more than the inexpensive model 505. The wooden cabinet has a nice mahogany veneer. Lettered in gold script over the screen are the words Carnegie Hall Edition.

Like the model 505, this set uses a row of pushbuttons for tuning. Unlike the early 505s and T-54s, however, it does not feature the obsolete channel 1. The rightmost "button" in the bottom row is a rotary fine tuning control.

From left to right, the three large knobs above the tuning buttons control horizontal/vertical, power/contrast, and brightness/volume. It takes a little while to get used to a power knob that also controls contrast, rather than volume, which has become the modern standard. In that respect, the T-67 is a little like my Sparton 1271 and Dominion Electrohome console radios, which paired the power switch with a tone control rather than with volume.

Cosmetic Restoration

I bought this set at a local shop for $125, and the price included a spare unused picture tube. It was a one-owner set purchased from a local estate. Here's the TV sitting in my study in the day I brought it home. As you can see, the cabinet was in good shape except for the odd scratch or two and normal wear around the knobs.

The next photo shows the cabinet drying in the sun after I touched up the finish. This consisted of giving the cabinet a light wipe with mahogany stain to darken the scratches, then rubbing off the excess. I'm not crazy about this technique because the oil-based stain can take days to dry in our humid climate, but it's an awfully easy way to revive a slightly scratched finish. This time, I diluted the stain with some lacquer thinner and it didn't take too long.

The gold-colored bezel surrounding the screen is made of plastic. The safety glass is very thick and appears to be made like an auto window, with a layer of plastic laminated between two layers of glass.

Electronic Restoration

This television has two chassis. The smaller rear chassis holds the power supplies and sweep circuitry and the larger front chassis holds the tuner and audio sections.

Hallicrafters used this chassis in four different models from 1947-1949. The T-61 came in a black bakelite tabletop cabinet with the same profile as this T-67. Model T-64 came in a tabletop or console wooden cabinet and gave you a choice of 10-inch or 12-inch screen, while model T-69 offered a 15-inch screen in a console wooden cabinet.

This set uses 23 tubes, including the picture tube:

The two chassis are removed in steps. First, you disconnect several inter-chassis cables and the picture tube cable, remove the mounting screws, and slide the rear chassis back.

Before removing the front chassis, you must unscrew the speaker from the top of the cabinet and unplug its cable from the chassis. Be careful not to spear the speaker cone on the mounting screws! Then you can slide out the front chassis.

After cleaning all the switches and controls with DeOxit spray, I replaced all of the capacitors in the power chassis. The next photo shows the original capacitors in place.

I then replaced a couple of weak tubes, reconnected the chassis on the workbench, and slowly brought up the power using a variac. To my delight, the TV had a nice bright picture and great sound. Here's what it looked like at that stage.

The picture had some distortion, as well as vertical and horizontal sync problems, but that's only to be expected in a mostly-unrestored TV of this vintage. On the whole, things looked very encouraging!

Next, I replaced the remaining paper and electrolytic capacitors in the tuner chassis. The next photo shows both chassis after recapping was complete. (See Replacing Capacitors in Old Radios for an explanation of how this is done.)

One of the original cardboard-covered electrolytics is still in place under the power chassis, although disconnected. The two new capacitors that replaced it were small enough to fit alongside the old one, and the old case made a convenient anchor for a plastic tie to secure the new leads. In other spots, I used the original metal clamps from the old caps to mount the new ones. Because power-supply capacitors carry high voltage, it's important to anchor them securely, as well as to insulate their leads.

When recapping was finished, I adjusted the various picture controls and was quite pleased with the picture quality. One defect remained, however, a vertical line running down the left half of the screen. In the next photo, you can see the line running past the newslady's nose.

I queried the rec.antiques.radio+phono newsgroup, and soon learned from TV veterans that this is "Barkhausen interference," caused by unwanted oscillation from the horizontal output tube (in this case, a 6BG6GT). The name is used, according to one old manual, because the oscillations are similar to those in a Barkhausen-Kurtz ultra-high frequency oscillator.

One characteristic of this interference is that it's more noticeable with weak stations than strong ones. In reading up on the topic, I learned about other, similar types of interference with amusing names such as "snivets" and "spooks."

The simplest cure for Barkhausen interference is to substitute other output tubes until you find one that doesn't oscillate. Another method is to place a small circular magnet around the tube and adjust it until the line disappears.

The 6BG6GT tube is not expensive, so I ordered a new one from Antique Electronic Supply. In the meantime, I happened to attend a swap meet and picked up a used 6BG6GT for a couple of bucks. The used tube didn't cure the problem, but the new one eliminated it completely.

The final photo shows the completed TV playing on my workbench. The picture is actually better than it appears in these on-air photos, which always end up somewhat blurry.

Only a couple of small adjustments remained. I slightly adjusted the yoke to make the picture perfectly horizontal, and touched up the oscillators for each channel so that you don't have to fiddle with the fine tuning control every time you change stations.

Final Thoughts

If only every TV restoration could be this easy! I was lucky in finding a well cared-for one-owner set, which was basically in fine shape except for aged capacitors. Now that it's back in the cabinet, I have hauled it up to our bedroom where it can be watched regularly. With a small amplified rabbit-ear antenna from Radio Shack, the reception is outstanding. Last night we watched the season finale of "The West Wing" and it never skipped a beat.

It's nice to have a spare picture tube in case this one gives up the ghost, or I happen to find another 10-inch TV with a bad CRT.