In some cases, technical information is no longer available. Video Sources Electronic sets from the U.S. will work with today's TV standards, even the sets made before World War Two. Those sets were designed for 441 line operation, but will work with the present 525 line system. For these sets, a 405 line test pattern generator is used to allow the set to work. Older 625 line VCRs will play back 405 line tapes.
Mechanical sets provide a real challenge.
The approach I have taken is to use a PC to convert 525 line videotaped pictures to either 30 or 60 line pictures. Presently, we are restoring several prewar sets. Every few days we will be updating our progress in this site. Because prewar sets are so rare, we take special care with them to keep them as authentic as possible. All electrolytic and paper capacitors are restored by hiding modern ones inside the old shells.