by Neil Bauman, Ph.D.
A lot of people think that t-coils and loop systems are a relatively new invention. I’ll bet you’ll never guess just how long t-coils have been available in hearing aids.
If you’re like most people, you probably guessed some time in the 1970s or 1980s. If you guessed that, you’d be way off base. In actual fact, the first hearing aid to have a t-coil was a vacuum tube table model that Tel-Audio came out with back in 1936!
Two years later, in 1938, Multitone of Great Britain produced their model VPM (vest-pocket model)—the first wearable hearing aid with a t-coil. Here in the USA, it took until 1946 before RadioEar produced their Multipower “Phonemaster”, the first American hearing aid with a t-coil. Since the 1950s, t-coils have been standard features on a number of hearing aids.
As some of you may know, I am the owner of the largest on-line hearing aid museum in the world.
Recently the museum acquired a Sonotone Model 200 transistorized body-style hearing aid made in 1956 with a built-in t-coil. That is nothing unique. But what was unique is that it came with a small loop pad that you could hook up to your TV and so listen to your TV via this loop pad. (I’m not aware of any other of these loop pads still in existence!)
You hooked the loop pad to your TV by simply clipping two alligator clips to the TV’s speaker wires. Then you set the loop pad down beside you and placed the body of your hearing aid on the loop pad and turned the mic/t-coil switch to the t-coil position.
If you’d like to see this Sonotone 200 hearing aid set on the loop pad, it is shown on the 11th picture down. Cool isn’t it? (For more information on this loop pad, click on the “Sonotone Miniature Loop Pad” link beside this picture.)
Compare this antique loop pad to a modern loop pad that is in use today.