From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Properties and development of paper and mica condensers.
| Identifier | WestWitteringFiles\H\November1921\ Scan32 | |
| Date | 24th November 1921 | |
| Contd. -2- HFC2/T24.11.21. The length of strip unwound was 30 feet. Taking the thickness of paper to be as previously stated, .00125", this gives average paper a di-electric inductivity of 6.23 which is higher than would have been anticipated with this material. We are asking Mr. Hall to investigate this material. Your suggestion that this paper may be made by the Japs is being acted upon in the hopes that we may obtain some in London from this source. In the meanwhile we are making progress with mica condensers. We can obtain mica, as stated, .001, .0005". It will be possible, as you suggest, to select mica thickness not to exceed an average of .00125" or even .001" if necessary, only this we fear will involve a considerable amount of scrap. It certainly appears at first sight that a mica condenser ought to have considerable more capacity than the paper, but particulars of the Bosch condenser show this to be not necessarily the case. We note that you agree to modifications being made to utilise the space to greater advantage, and details are being got out in accordance with this and with condensers we have already made, in which this better utilisation of space is adopted. We have, for instance, arrived at a 90% efficiency figure which means a capacity of .225 mf. working to the Lcd. design. We actually now have a condenser of .33 mf. in which the bolt holes are absent and thinner packing pieces are provided, so that this capacity will go into the S'K' 838Y (100 L) (2' H' 182' 10-12-20) C' 3074 Contd. | ||