Clearing out my father's home, I came across a canvas bag marked SYKO CIPHER DEVICE, unfortunately no device inside. He was an LAC in the RAF so this was quite a surprise, and I have found very little about who would have been issued with these. Only part of his service I think could relate to this is he was in 58 RSU recovering crashed aircraft in the Western Desert (that was mid 42 to mid 43), though does this mean my father was also the 'radio operator' in the RSU column ? Unfortunately he has serious dementia so I can't ask him, and seaching the web has revealed very little about how many were issued and to whom, and I haven't found any pictures of a canvas bag like this, though I read that Bletchley has a device and its leather case/box.