I recently noticed a dial on a radio early 30s that showed not only the numbers (not related to frequencies) but actual radio stations call signs like 3KZ ,3AW etc. not sure if it was original.
It promoted my interest in understanding when did radios first indicate on their dials,the radio station call signs in Australia. How many stations were there on the dial in the first year they appeared.
I know this might be State manufactured dependent, but tring to have a guide to timelines related to what was on Australian Radio Dials.
Any info is most welcomed.

In the 1920's, prior to single knob tuning, a simple, generally 0 to 100, scale was used and one kept a log of the number for each tuning dial. An Atwater Kent 20C is a classic example. As manufacturing techniques improved, the multiple tuning caps could be ganged together to provide a single knob but generally a 0 to 100 scale.

In the late 1920's, the scale could be calibrated in wavelength, about 200 to 550 metres and an AWA 55E is such an example. In the very early 1930's with the advent of smaller, bakelite radios, dials could include both the station identifier and the wavelength. The early Radiolettes followed this path. As the frequency of a station became more recognised, the wavelength marking was dropped and replaced by frequency in about 1936 - 37.

So to answer your question, I would say stations appeared from about 1932.On a 1937 Radiolette, there are approximately 65 stations marked. If someone has an earlier radio, a station count would be interesting.

Harold

Thanks Harold, the use of 200-550 metre scale, does seem consistent with what I have observed with the Australian 1930s radio's I have.
Though I have only seen on my Australian 1940's radio dials with the actual radio station identifier, I have never actually countered how many stations but I will and will report back.

Radio Trade Annual 1937 has a listing of stations, earlier versions will also likely have? Spacing at that time will be listed as 10 Kilocycles. with several as now on the same one.

With the change of spacing came movements all over the place. 2AY & 3SR two closest to their original position. Many early sets never went past 1500kHz.

Having "stations on the dial" was a sales feature that was introduced in the mid 30's. A lot of stations meant this was a POWERFUL radio!

AM radio callsigns and dial positions have changed little since then, despite the change to 9kHz spacing. The band was crowded by the mid 30s and relatively few stations have been added.

A good source of such information is Australian Radio History by Bruce Carty.

Not sure if it's still in print.