Zenith Neon Radio-TV Sign (1950s)

           

This charming neon sign popped up in a local craigslist ad, and after doing a little research, I decided to buy it. The sign was missing the power supply and the owner had no idea whether it worked, but the glass tubing looked intact, so I took a chance.

First Look

Here are front and back views of the sign in as-found condition:

  

The sign's high-voltage electrodes are mounted at the top. Each electrode has two wires:

Although the tubing and metal frame were intact, the opaque "blockout" paint had flaked off in many spots:

     

The blockout paint hides parts of the tubing that you don't want to light up when the sign is turned on. This photo of the unrestored sign shows the result of missing paint:

To the right of the H in Zenith, you can see light "leaking through" the places where blockout paint has fallen off. You can see smaller leaks between the I and O in RADIO and at the upper right corner of the N.

Restoration

You can't light up a neon sign without a high-voltage power supply. I asked for advice in the antiqueradios.com forum and learned that a Ventex VT9030D-120C supply would work with this sign. I ordered one and the sign lit up, as shown in the previous photo. Here's a photo of the supply:

The "brick" portion of the power supply is about six inches long, similar to a laptop computer supply. The two bare leads supply the high voltage; those will be connected to the sign's electrodes. The power supply has a pull-chain switch and its AC line accepts a standard computer-type cord.

The Ventex HV supply has a three-level output switch (Hi-Mid-Lo). My sign lights up nicely at the low output setting.

My sign came with two 15KV-rated cables connected to its electrodes. These will come in handy if I decide not to mount the Ventex power supply right next to the sign.

Before I hang the sign, I need to get insulators for the electrodes and repaint the spots where blockout paint is missing. A member of the antiqueradios.com forum sold me a couple of insulators and a little bottle of Stazon paint:

To repaint the flaked tube areas, I cut the foam brush down to a narrow size and worked slowly, bracing one hand with the other to avoid slopping paint onto the lit portions of the tubes. This job took a long time. The closer I looked, the more flaked areas I found! After finishing the blockout paint, I painted the metal frame with Rustoleum flat black.

These hollow rubbery insulators are the "bend-back" type, open at one end and closed at the other. The larger diameter of the insulator fits the tubing and the smaller diameter fits the high-voltage cable, which is bent back and contained inside.

It's important to connect the high-voltage supply wires securely to the sign's electrodes, but soldering is a little risky because applying too much heat might crack the tips of the glass tubing. I began by carefully straightening the electrode wires and scraping them to remove corrosion. Then I twisted and crimped the wires to the supply wires and taped most of the junction with a special varnished cambric tape that is rated for 90 KV.

Next, I slipped the insulating boot over the junction. A little farther down the frame, I secured the HV cable to the frame with two black zip ties. The ties prevent force from being applied to the electrode junction when you move the sign around.

Neon tubes haven't really changed in the fifty-odd years since this sign was made. One day, outside our local grocery, two guys were installing a new neon sign for a Mercury's coffee shop. Just as in my sign, the neon elements are glass tubes with a couple of electrodes, and blockout paint over the segments that they don't want to illuminate.

  

Final Thoughts

A lighted neon sign makes a challenging photographic subject. In life, the sign is a much deeper pink and orange than what appears in my first photo, where the lit tubes tend to wash out toward white. If I succeed in taking a better photo of the restored sign, I'll post it here.

In case you're wondering, I paid $150 for the sign itself and about $75 for the new power supply. Based on comments from other collectors, that seemed like a reasonable price.

If you are looking at neon signs for sale, be aware that it is extremely risky to ship them anywhere. I would not have considered buying this sign if it hadn't been available within a short driving distance. If a seller brings such a sign to a shipper for packing, they will typically wrap it in bubble wrap and fill the box with foam peanuts. That's fine for sturdier objects, but even a slight pressure of packing material against the glass tubes may break them. When these signs were new, they were shipped in open wooden crates. The frame of the sign was bolted to the frame of the crate and nothing but air was allowed to touch the glass.

I'm just guessing about the date when this sign was made. If anyone has more accurate information, please send me an email.

©1995-2023 Philip I. Nelson, all rights reserved