Columbus / Pacific / Stella / Courtenay model 38 Spiral Dial
Mar 14, 2022 18:08:10 GMT 12
Richard likes this
Post by Steve on Mar 14, 2022 18:08:10 GMT 12
Some of you are aware I'm writing a book on Radio Corp - and this process has lead me down a few rabbit holes...
One such descent into madness was to do with the Spiral Dial found on Radio Corp NZ models 38 (6V+), 43(8V+ all metal valves) and 77 (battery version)
I had always considered this to be the work of a mad genius... a masterpiece. A 2-foot-long dial scale in a tight circular pattern with three separate band tracks all laying together - and a point of light (or line of light) which followed whichever band track you selected to show tuning.
And I always wondered why there seemed to be so few around... I also wondered why the design didn't last longer (the short answer to that one is the model 75 bandspread game-changer which was released within a couple of years of the 38).
I've fixed a couple of these dials now and they are almost Philips-like in their complexity, and every bit as frustrating - but quite clever in design.
It turns out the dial mechanism caused a lot of angst in the factory, and had the factory manager and the managing director, Mr William Marks himself, in hot water with both the board of directors and the companies waiting to sell their new models in the 1937 sales year (Turnbull & Jones for Courtenay, Pacific Radio Co Ltd for, well, Pacific, Cory-Wright & Salmon for Stella and their own Columbus Radio Centre stores). There were engineering hurdles a-plenty and many delays and cost over-runs which eventually meant they missed their deadlines - upsetting everyone in the process and making all those brands late to market for that year.
Board meeting notes and a letter from Turnbull and Jones (who had a senior member of their staff on the board) showed how bad it had gotten, with vague threats that people and costs needed to be reigned in and possibly replaced, and the sets just needed to be finished and sent out.
In fact, I have one model 43 set in my possession which has a plain round dial fitted. It's an oddity that I was, at first, unable to explain. No other model from Radio Corp had a 3-band round dial so it couldn’t be a replacement for a broken mechanism… but finding all this historical evidence of the proverbial brown stuff hitting the twirly thing it makes it very likely that these plain dials were a hasty solution to the delays and would have enabled Turnbull and Jones to get their high-end 1937 sets to market, albeit without the new fancy spiral mechanism.
This is all really interesting (to me anyway) but yesterday evening I discovered a note on a handwritten page that was amongst a pile of papers that were from Cory-Wright & Salmon (Cory-Wright was also on the board) - and it had two words I’d never properly seen before (although I've read this page before - there is a lot of interesting stuff on it)… and they caused me to go searching.
Our Mr Irvine was the factory manager who's butt was in a sling over the spiral dial mechanism. One member of the board going so far as to suggest Jens Jensen (who was here setting up the speaker manufacturing plant and was about finished and ready to head home to California) should, on his return to America, be engaged to find a competent person to take his place. But 'Irvine Patent'? Could there be a patent for the dial mechanism? It seems logical in hindsight given its complexity and potential to provide a better experience for tuning short wave bands in particular. So a good while later I managed to find it - applied for way back in 1936 (which shows how long it had been in planning for), submitted in 1937 and granted in 1938.
The patent, number 76664 (and 78066 which seems to be combined with it) is titled "An improved scale and indicating means for use in connection therewith" - which is odd... and not very search engine friendly... but here is the diagram for it:
Which is about the most useful piece of repair information I have ever come across for the dial itself. It also shows how incredibly complex it all was.
The patent document is 20 pages long - its worth a read. You can download it by going to the NZ Patents Search site and putting in the patent number (76664) in the case number box, then going to the documents tab and downloading the Complete Specification document.
So there you have it - a saga of epic proportions that ended in a short-lived but incredible awesome (personal opinion, your mileage may vary) dial that almost wasn't.
One such descent into madness was to do with the Spiral Dial found on Radio Corp NZ models 38 (6V+), 43(8V+ all metal valves) and 77 (battery version)
I had always considered this to be the work of a mad genius... a masterpiece. A 2-foot-long dial scale in a tight circular pattern with three separate band tracks all laying together - and a point of light (or line of light) which followed whichever band track you selected to show tuning.
And I always wondered why there seemed to be so few around... I also wondered why the design didn't last longer (the short answer to that one is the model 75 bandspread game-changer which was released within a couple of years of the 38).
I've fixed a couple of these dials now and they are almost Philips-like in their complexity, and every bit as frustrating - but quite clever in design.
It turns out the dial mechanism caused a lot of angst in the factory, and had the factory manager and the managing director, Mr William Marks himself, in hot water with both the board of directors and the companies waiting to sell their new models in the 1937 sales year (Turnbull & Jones for Courtenay, Pacific Radio Co Ltd for, well, Pacific, Cory-Wright & Salmon for Stella and their own Columbus Radio Centre stores). There were engineering hurdles a-plenty and many delays and cost over-runs which eventually meant they missed their deadlines - upsetting everyone in the process and making all those brands late to market for that year.
Board meeting notes and a letter from Turnbull and Jones (who had a senior member of their staff on the board) showed how bad it had gotten, with vague threats that people and costs needed to be reigned in and possibly replaced, and the sets just needed to be finished and sent out.
In fact, I have one model 43 set in my possession which has a plain round dial fitted. It's an oddity that I was, at first, unable to explain. No other model from Radio Corp had a 3-band round dial so it couldn’t be a replacement for a broken mechanism… but finding all this historical evidence of the proverbial brown stuff hitting the twirly thing it makes it very likely that these plain dials were a hasty solution to the delays and would have enabled Turnbull and Jones to get their high-end 1937 sets to market, albeit without the new fancy spiral mechanism.
This is all really interesting (to me anyway) but yesterday evening I discovered a note on a handwritten page that was amongst a pile of papers that were from Cory-Wright & Salmon (Cory-Wright was also on the board) - and it had two words I’d never properly seen before (although I've read this page before - there is a lot of interesting stuff on it)… and they caused me to go searching.
Our Mr Irvine was the factory manager who's butt was in a sling over the spiral dial mechanism. One member of the board going so far as to suggest Jens Jensen (who was here setting up the speaker manufacturing plant and was about finished and ready to head home to California) should, on his return to America, be engaged to find a competent person to take his place. But 'Irvine Patent'? Could there be a patent for the dial mechanism? It seems logical in hindsight given its complexity and potential to provide a better experience for tuning short wave bands in particular. So a good while later I managed to find it - applied for way back in 1936 (which shows how long it had been in planning for), submitted in 1937 and granted in 1938.
The patent, number 76664 (and 78066 which seems to be combined with it) is titled "An improved scale and indicating means for use in connection therewith" - which is odd... and not very search engine friendly... but here is the diagram for it:
Which is about the most useful piece of repair information I have ever come across for the dial itself. It also shows how incredibly complex it all was.
The patent document is 20 pages long - its worth a read. You can download it by going to the NZ Patents Search site and putting in the patent number (76664) in the case number box, then going to the documents tab and downloading the Complete Specification document.
So there you have it - a saga of epic proportions that ended in a short-lived but incredible awesome (personal opinion, your mileage may vary) dial that almost wasn't.