1. Skip to Menu
  2. Skip to Content
  3. Skip to Footer>

Time-Line computer Archive Ltd is a not for profit company, our aim is to collect, restore and exhibit all types of early computers and electronics.

We hope that our website will give an insight to the development of computing and will help give inspiration to other people to collect rather than throw out historical electronics.

We also would like to make a record of peoples experiences of early Computing and Electronics primarily from Scotland and the North of England but also from Great Britain generally. If you have any Experiences of early computing or Electronics please don't hesitate to contact us.

Paperclip Computer

PDF Print E-mail


This decoder converts binary code to decimal numbers










For a more detailed description

click on



Like the Encoder, I mounted the switches and bulbs on perspex, I found

the easiest way to fit the switches was to drill, then ream the holes and

then finish to size using a small file.










You can see in the photographs I used old switches, they were donated

to the Museum along with other items by Mrs winterburn from a her

late husbands estate, the only thing I had to do to them was to take off

the old solder to expose the holes on the wiring tangs, this allowed me

to wire wrap the connections.











I haven't built the Decoder to the sizes specified in the book , I've

also altered the design of the bulb harness as well.












I didn't encounter too many problems other than scratching and cracking

of the perspex , same as the encoder.

Wire wrapping the switches was quite fiddly, but managed to get a

good enough connection to allow the decoder to work.

I also made a large drawing with all the switches and wire connections, this

helped by creating a visual reference once wiring was under way.










I really enjoyed this build and look forwards to my next module “ Memory Drum”




Paper clip computer (Encoder)


The Encoder converts Decimal to Binary code ready for computer

usage. Please click on read “Read article” for progress.











Two steps forwards one step back, that is how the Encoder developed.

With making the top sheet out of perspex, it through up problems with cracking

and scratching, but on the whole I think it was worth the extra effort.

Other problems encountered were, finding matching bobbins and getting the

yellow insulation tape to stick to the copper.

The book says, make a clip and string it between two dowels to act as the

connection between the bobbins and the bulbs, I found that I could not get the

right tension and the clips damaged the yellow insulation.

I changed the design and bonded the clips onto one dowel using car bodyfiller, this

has definitely done the trick, the clips ride over the insulation without damaging it.








A slightly different bulb assembly and bulb clip.











Finish assembled and tested.











There is a really interesting set of videos on YouTube that go through the programming

sequence for the paper clip computer ( click on link).


Next build, (Decoder).