Certain users have reported that they get different readings from the same vacuum tube after the VT1000 Valve Tester has been moved. According to Orange, this is to be expected; the tube analysis system in the VT-1000 is sensitive to temperature. For best results, after moving the unit to a new location allow it to acclimate for 1.5-2 hours before using it to test a tube, particularly if there is a temperature difference between the two locations or if the unit has been exposed to varying temperatures during transport.
