Thanks, though it isn't an 026 its an 029, the one with the squared off case. I happen to have a jelly mould one, though it is an 836 with all the extra bells and whistles like a programming patch panel in the left side pedestal. Trouble is it does not work and it has about 3 times the number of relays as a standard 026 and I can't get circuit diagrams for it. I found someone who could supply them for 100 dollars but he wanted a cheque from a US clearing bank which of course I can't do, and things went quiet when I asked about alternatives. Aha! I am half of the ICT 1301 restoration project. About the same age, the 1301 was announced 1959 and first shipped in 1962. The project was started by BTM, the British Tabulating Machine company which had just stupidly given up the rights to all IBM's patents throughout the British Empire, which by then was shrinking fast. I saw a picture of three of your guys standing around an online card punch and I planned to send you a picture of the two of us standing around our almost identical online card punch, though I'm sure the electronics underneath are different. The relays and the two banks of bakerlite cams are probably the same. Our has a ancient design of board with a Z80? valve on it which powers down the motor if the machine has not been used for a while. What oil do you use in your Geneva gear box? I know it is slightly too modern for my 1301 but my new acquisition is an 029 model C and there was an IBM Field Engineering manual in it. It is not the more modern one with reed relays, it still has the IBM wire relays used in the 026/836. Looking at the manual again it just says model 29, but I always though they were called 029. Maybe I've got it wrong, or maybe they were only called 029 in the UK. A four watt 115v bulb! Sourcing one of those locally might be tricky. The machine was powered up in the states before shipment so I might be lucky with this. Er, no valves in either the 29/029 or the 836. There were some in the verifier. OK, I might have a spare from the verifier. Absolutely. Back in 1979 I made that mistake on the 836, I tried to clean the print head with a rag pulled side to side - I bent all the print wires and it never printed again, part of my reasons to buy the 29/029. Not that I've given up totally on the 836 but it is WAY down the priority list. Highest priority is to get the check read brushes on the online punch working 100% so I can use it to (slowly) read the precious old cards I have without wrecking them so badly they can't be manually read and re-punched on a keypunch. Very interesting. Thank you very very much. Impressive! Not a transistor in sight either. Hmm, so 10 Hz off of 60 means 10/60 so 16.667% x 48v = 8v so output will be 40v instead of 48. For relay logic that doesn't sound too bad to me but then I've never designed relay logic (except for model railways when I was a boy). Thanks and good luck with the 1401 restoration.