I've been using this Validator for 33+ years, and it is 36 years old or so, and we bought it with a PH9 motorized head, that we finally 'upgraded' to a PH10+ 3 eyars ago or so. We also have a PH1, but in all my years, I've only used it on 1 job, when I made the bridge operate like an ARM. I had EVERY extension on it, 50mm, 100mm, 200mm, an 80mm long extension-type knuckle, the TP2, then had about 100mm of probe on that, all so I could check some things on a car door fixture, with the fixture sitting on blocks, and extending off both sides of the machine. I had to sit under the bridge to see and get to what I had to check on it.
'good enough' as they say. The PH1 is all mechanical 'smooth', with no 'stops', you crank down the bolt that holds it at the position you want, it doesn't move, they only accuracy issue could have been with the length of probe on the TP2, and with the tension turned up, it gave 'funny' size results, but STDEV was fine, so it was good to use. MAX length (normally) for a TP2 was supposed to be 50mm, but that was mostly to prevent false triggers. Yeah, I had it cranked, no false triggers!
