Improvements in Tuning dials

[crackle]

I wonder if there any other makers who had innovative tuning dials to make it easier for the ordinary man or lady of the house to find and tune into different stations.

KB had the "Alphadex Dial" in the late 30's, and I happen to think it ia a very good idea, making it easy to locate any station you wanted.

You can see an example here in the KB 650.

Mike

[Cobaltblue]

Murphy did something similar with their Alphabetical tuning

https://www.radiomuseum.org/r/murphy_a38c.html

http://www.murphy-radio.co.uk/murphybilia/cats/1937.pdf

The Murphy collectors will be able to say which was the first set they used it on possibly the A34?

Cheers

Mike T

[turretslug]

Bush "Teleflic"?

https://www.radiomuseum.org/r/bush_sw45sw_4.html

[Cobaltblue]

Cossor and I think Philco used a Teledial system

https://www.gracesguide.co.uk/images...2PP-Cossor.jpg

I have a couple of sets with Teledial and I don't find it that good (Maybe I need to investigate the Mechs)

Cheers

Mike T

[Argus25]

The most interesting and innovative vintage radio dial I know of is the Philco "Cone Centric" dial.

There was an array of small cones for station offsets . The tuning knob revolves around the dial perimeter and a larger knob, concentric with that, engages the perimeter of the dial for fine tuning.

The common model that had this was the 38-7 which had a very interesting Art Deco cabinet. Also the translucent dial itself had astonishing detail and accurate calibration markings and was diffusely lit by a lamp spaced well back from the dial so the illumination was very even.

All in all, the most remarkable creative and brilliant radio dial I have even seen, on any radio, made anywhere, by any radio manufacturer, ever.

It is quite a mechanism too with cast alloy componentry. The dial output shaft also connected to the V/C with a very clever mechanism of a spring loaded split gear, which completely eliminated backlash in the mechanism.

Interestingly there were a number of curious innovations in the 38-7 radio elsewhere. One was a single turn of wire placed around the IF transformer coil and placed in series with the cathode of the 6k8 IF valve, also an ingenious and futuristic delayed AGC system using a 6J5 as an AGC detector. So the designers got 10/10 for this radio.

https://www.google.com.au/search?sxs...w=1280&bih=666

It's come full circle, modern DAB radios merrily give an alphabetic list of stations (loads of them) to choose from. Such is progress.

[G6Tanuki]

I remember a rather-impressive US-built radio (Philco? it has US-style 2.5V-filament valves) I came across ages ago that took an innovative approach to the old issue of the AM/MW waveband being spread-out at one end of the tuning dial and crushed-up at the other.

Rather than the pulleys on the tuning-cord/dial-pointer-drive being circular, they were in the form of a set of flat helices - arranged so that as one helix's radius reduced with rotation the other helix's radius increased. The result was a really-nicely-linear tuning with an expanded HF end - great for accurate tuning of "Lucky Luxembourg" on 208M and the pirate stations of the era.

[lloydwells]

This is one of my favourite sets but not one of my favourite scales. I'm assuming sound sales weren't for the the likes of people who might want a station name or two but I think the lower half corresponds to BBC stations of the time ?

[turretslug]

Originally Posted by G6Tanuki

Rather than the pulleys on the tuning-cord/dial-pointer-drive being circular, they were in the form of a set of flat helices - arranged so that as one helix's radius reduced with rotation the other helix's radius increased. The result was a really-nicely-linear tuning with an expanded HF end - great for accurate tuning of "Lucky Luxembourg" on 208M and the pirate stations of the era.

Designed by someone with a background in clocks? - in the days when that would have been a reasonably mainstream skill! I'm surprised that there weren't more "linearising"- type tuning drives around, seeing as some effort was made in the shaping of gang capacitor vanes to reduce cramping, yet this alone only partly eases the effect.