I have acquired a 1946 Kingsley Ferrotune radio chassis that looks interesting because it does not use a tuning capacitor gang but an inductor. It is missing the tuning unit cover, has anyone else got one of these radios?
Apparently the where sold as a kit for the home constructor.


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Thanks,
Gary

I dont know if this is the Kit you have but you'll find a pdf at Kevin Chant's.

http://www.kevinchant.com/kits.html.

Does look like it and yes missing a cover (if thats the beastie)

Sure those that know will chime in.

HTH

Many car radios used inductor tuning, so you might see what such radios used for cover material (or maybe you'd luck out and find a usable cover, if you do also buy a lottery ticket ). I think such cover material was usually aluminum or copper, but not steel (just like the material used for IF transformer cans), if you want to make a cover.

Its not like the car radio tuning assembles I have seen. See below.
I can make a cover if we cannot got a photo of the original.
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Looking at the Ferrotune pdf's on Kev's site the High Quality 6 has an interesting audio stage. Could this be the first radio in Australia to use DC coupling between audio stages?

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They may have called Ferrotune after the tuner? Permeability tuning was used in some valve sets other than car, and the throttle position on CM Valiant.

That sort of tuner is less affected by dust & moisture.

DC coupling was rare in valve sets but there are valves with two elements DC coupled within You could almost call a 6J8 and similar DC coupled as the Triode g1 is shared with g3 of the Heptode.

I have had an STC lately missing sides and a 1929 Lyric missing a Faraday cage for the first four Valves. merely a case of measuring up & then bending up a new one.

Marc

QUOTE: an interesting audio stage. Could this be the first radio in Australia to use DC coupling between audio stages?

The downside of this DC coupling is that you're burning power in that big cathode power resistor, power that could have been used for more audio output power. Sure, it's off the mains, but you need a bigger power transformer to provide that wasted power, which costs more. That's why most everyone used coupling caps, as you don't need DC for audio anyway. Our ears don't hear DC either.

Just found this ad from Radio & Hobbies, page 18, Feb 1946. It has a good illustration of the cover.

It looks like the cover is transparent, some sort of plastic. It's probably missing because it disintegrated.

Good find Mono. Just what the doctor ordered.

Thanks GTC. I must admit I didn't notice the cover was transparent until Scraps pointed it out. Perhaps there is a reason why the cover is non-metallic.

Yes, that was a good catch by Scraps. I suppose it could be non-metallic either to avoid affecting the Q of the coils, or to feature the mechanism (though you'd have to open up the radio to get any benefit from that, so probably not a likely reason).

I'll let you know once I get it going

Hi Mono,
Where did that ad come from? I'll upload it to the Museum if its ok by you?
Cheers,
Gary

Hi Garyoz.
I scanned the ad from the February 1946 Radio & Hobbies mag. I'll send you a copy. My email details are not hidden.

Cheers.