[Heathkit] re voltage calibrator

Murray Grandy mgrandy at telus.net
Sat Apr 1 20:08:42 EST 2006


Thanks for all the great suggestions on voltage calibrator. I do own the Heathkit IG-4505 scope calibrator, a nice unit but puts out a square wave at 100 volts. I was checking hi voltages on some old power transformers and though that things we reading to high. I was using an Ostra DM3500 I think is the model number. I then checked with my Beckman both expensive meters, and found the readings to be closer to what I thought it should be. I know just reading open circuit windings are not accurate, but it seemed to me the meters should be at least within a volt or two of each other. Anyway, the problem turned out to be a very low 9 volt battery in the Ostra DVM and no indication. The Beckman does have low battery indicator. I changed the battery in the Ostra and now both meters are exactly the same, I mean both read like 428. The strange thing is I would expect the meter with low battery to read low. Just goes to show how little I know.
Murray


More information about the Heathkit mailing list