The idea[]
Raytheon had already entered the hearing-aid market in the mid 1930s with the invention of the sub-mini electrical valve (vacuum tubes). In order to keep there market share and perfect their product's reception the firm decided to experiment with very early transistor technology. They thus started the silicon based electrical era.
Manufacturing[]
N\A, but probably akin to then Western practices.
Casing[]
A small oblong, painted, metal or PVC case full of epoxy resin or glass powder and with 3 wire legs at the bottom, protruding through a PVC cap at the bottom. It was initially housed in pre-a cast epoxy oblong case during it's first months of use.
Stats[]
| Category. | Statistic. |
|---|---|
| Designed in. | 1947-48. |
| Made in. | 1952. |
| Transistors per chip. | 1. |
| Power supply. | Battery and low voltage power. |
| Still in use. | No, but may are still in private hands, corporate archives and at museums. |
| Nationality. | American. |
It was one of America's first moves in to the modern electrical business and it was seen as a national icon at the time. It was a historically important transistor type since it was the first in the world to be produced in large quantities for commercial applications.
Also see[]
References[]
- http://semiconductormuseum.com/MuseumStore/MuseumStore_CK718_Index.htm
- https://sites.google.com/site/transistorhistory/Home/us-semiconductor-manufacturers/raytheon-part-one-2
- https://images.search.yahoo.com/search/images;_ylt=AwrBT9r77epXpOwAdVxXNyoA;_ylu=X3oDMTEyaHZjYzhtBGNvbG8DYmYxBHBvcwMxBHZ0aWQDQjE4NzlfMQRzZWMDc2M-?p=Raytheon+CK718+PNP+Germanium+Hearing+Aid+Transistor&fr=yset_chr_cnewtab
- http://semiconductormuseum.com/PhotoGallery/PhotoGallery_CK718.htm
- http://semiconductormuseum.com/MuseumStore/MuseumStore_CK718_Index.htm
- https://www.amazon.co.uk/s/?ie=UTF8&keywords=pnp+transistors&tag=mh0a9-21&index=aps&hvadid=3835315444&hvqmt=b&hvbmt=bb&hvdev=c&ref=pd_sl_2w45xvzbxb_b
- http://www.idealprice.co.uk/compare.html?q=Pnp-Transistors&ort=Pnp-Transistors-Sale&adid=iaCkp56y0aFfh9PD0aSbptXR1aRYosyfs5%2BiYLXUxJ%2BlnNTW0qOlWdSfypKnpofFy5KkcLE%3D&baa=P&utm_source=bing&utm_medium=cpc&utm_campaign=nt_P_1&utm_term=%2BPnp%20%2BTransistors&utm_content=Pnp%20Transistors
- http://uk-prices.com/products/Digital%20Hearing%20Aids/
- https://www.reference.com/web?qsrc=999&qo=semQuery&ad=semD&o=38043&l=sem&askid=3425ea56-7062-4e2b-8dcc-3d325ad0056b-0-rf_msm&q=pnp%20transistors&dqi=Raytheon%20CK718%20PNP%20germanium%20hearing%20aid%20transistor&am=modifiedbroad&an=msn_s
- http://www.eevblog.com/forum/chat/vintage-raytheon-ck721-transistor-found/
- http://www.decadecounter.com/vta/tubepage.php?item=27
- http://chettinadtech.ac.in/wr/temp%2002/UNIT%20II%20for%20cseit.pdf
- https://prezi.com/-egwlvv9opig/the-history-of-transistors/
- http://semiconductormuseum.com/MuseumStore/MuseumStore_CK718_Index.htm