25-06-2011, 09:33 AM
I bought this curious little repro set from a local acquaintance in 2004.
At first sight, this intriguing little one-valve radio looks like a pre-war vintage "breadboard style" radio. It's on a wooden box type base, about 9" x 6", and about 2" high. It has one four-pin pre-war Marconi valve, (no markings!), one fixed basket weave coil, and two moving ones - one for tuning and one for reaction, which can be swung to and fro with levers across the fixed one.
There's a flying lead that can be plugged into one socket or another to introduce an additional fixed capacitor to expand the tuning range of the coils. It has one grid leak resistor mounted above the breadboard, and has a small ‘modern’ metal-clad transformer, (dated 1972) to enable low resistance as well as high resistance headphones to be used. It has a battery holder for the heater voltage, and at first I was puzzled as to where the HT supply was meant to come from. I then noticed a row of four pairs of studs on the underside back skirt of the wooden box, which are M/F stud connectors for four PP3 9V batteries in series to give 36V - quite low for HT, but presumably high enough for the (unidentified) valve.
It was bought in Australia as a Christmas present for a teenager back in the early 1970's - a local acquaintance who was born and grew up in Melbourne, Australia, but now lives in Beverley, East Yorkshire. It’s called a "Unidyne 1A". There is no maker's name on it, and a search on internet drew a blank. I therefore contacted Warwick Woods, President of the Australian Society Vintage Radio who responded saying: ‘Your little kit set is a Unidyne that made it's appearance in 1983 and was initially produced by a company in Queensland. Later it seems to have been taken over by Richard Wilson who ran a small electronics manufacturing company in Ballarat, Victoria. Attached to his factory was the small 'Orpheus Radio Museum' that contained a number of interesting old receivers. Unfortunately the museum was closed a number of years ago and the contents, I believe, sold off’.
Warwick was able to locate an article on the Unidyne that was published in 'Electronics Australia' in 1983 (now defunct) and kindly forwarded me a copy. He also found an advert for the set, from Orpheus, that was printed in 1992, after which time the kits seemed to disappear from the market.
The filament of the valve is intact, and I’ve tried some batteries in it, attached an aerial and earth but not a sound out of it. I haven’t bothered trying to troubleshoot it as it’s really just a curio. Although it’s ‘modern’ rather than a genuine vintage, nevertheless, it’s some thirty years old, and some of the components are from the 1920s/30s. It’s quite nicely made, and I guess it was quite a nice Christmas present for a young boy to have received I doubt that many were sold, and even fewer probably survive.
Footnote:
The Australian Vintage Radio Society has been re-named recently ‘Vintage Radio & TV' to reflect the interest in vintage TVs. I’m not a member of the forum, but the link to the website and forum is here, which might interest forum members:
http://vintage-radio.com.au/
I’ve attached some pics of the set and a copy of the advert, which doesn’t mention any price. However, the building instructions from 1983 in Electronics Australia indicate that the full kit was priced at $79.5 AUS, plus $5.00 AUS postage. At today’s exchange rate (1.52 $AUS = £1.00 GBP) that puts the price in 1983 at £55.60. Accounting for UK historical inflation, that would equate to approximately £140 GBP ($213 AUS). This is of course only an approximation, and doesn’t take account of differing exchange rates and inflation rates of the two countries since 1883. Quite an expensive present for a child!
I’ve not attached the six-page article from Electronics Australia as it runs to 4.8mB, but if anyone’s interested, I’ll happily e-mail it to them if they PM me.
Hope it's of interest.
David
At first sight, this intriguing little one-valve radio looks like a pre-war vintage "breadboard style" radio. It's on a wooden box type base, about 9" x 6", and about 2" high. It has one four-pin pre-war Marconi valve, (no markings!), one fixed basket weave coil, and two moving ones - one for tuning and one for reaction, which can be swung to and fro with levers across the fixed one.
There's a flying lead that can be plugged into one socket or another to introduce an additional fixed capacitor to expand the tuning range of the coils. It has one grid leak resistor mounted above the breadboard, and has a small ‘modern’ metal-clad transformer, (dated 1972) to enable low resistance as well as high resistance headphones to be used. It has a battery holder for the heater voltage, and at first I was puzzled as to where the HT supply was meant to come from. I then noticed a row of four pairs of studs on the underside back skirt of the wooden box, which are M/F stud connectors for four PP3 9V batteries in series to give 36V - quite low for HT, but presumably high enough for the (unidentified) valve.
It was bought in Australia as a Christmas present for a teenager back in the early 1970's - a local acquaintance who was born and grew up in Melbourne, Australia, but now lives in Beverley, East Yorkshire. It’s called a "Unidyne 1A". There is no maker's name on it, and a search on internet drew a blank. I therefore contacted Warwick Woods, President of the Australian Society Vintage Radio who responded saying: ‘Your little kit set is a Unidyne that made it's appearance in 1983 and was initially produced by a company in Queensland. Later it seems to have been taken over by Richard Wilson who ran a small electronics manufacturing company in Ballarat, Victoria. Attached to his factory was the small 'Orpheus Radio Museum' that contained a number of interesting old receivers. Unfortunately the museum was closed a number of years ago and the contents, I believe, sold off’.
Warwick was able to locate an article on the Unidyne that was published in 'Electronics Australia' in 1983 (now defunct) and kindly forwarded me a copy. He also found an advert for the set, from Orpheus, that was printed in 1992, after which time the kits seemed to disappear from the market.
The filament of the valve is intact, and I’ve tried some batteries in it, attached an aerial and earth but not a sound out of it. I haven’t bothered trying to troubleshoot it as it’s really just a curio. Although it’s ‘modern’ rather than a genuine vintage, nevertheless, it’s some thirty years old, and some of the components are from the 1920s/30s. It’s quite nicely made, and I guess it was quite a nice Christmas present for a young boy to have received I doubt that many were sold, and even fewer probably survive.
Footnote:
The Australian Vintage Radio Society has been re-named recently ‘Vintage Radio & TV' to reflect the interest in vintage TVs. I’m not a member of the forum, but the link to the website and forum is here, which might interest forum members:
http://vintage-radio.com.au/
I’ve attached some pics of the set and a copy of the advert, which doesn’t mention any price. However, the building instructions from 1983 in Electronics Australia indicate that the full kit was priced at $79.5 AUS, plus $5.00 AUS postage. At today’s exchange rate (1.52 $AUS = £1.00 GBP) that puts the price in 1983 at £55.60. Accounting for UK historical inflation, that would equate to approximately £140 GBP ($213 AUS). This is of course only an approximation, and doesn’t take account of differing exchange rates and inflation rates of the two countries since 1883. Quite an expensive present for a child!
I’ve not attached the six-page article from Electronics Australia as it runs to 4.8mB, but if anyone’s interested, I’ll happily e-mail it to them if they PM me.
Hope it's of interest.
David
