bap8guy | Gertsch RT60 Unit 3b @bap8guy | Uploaded May 2020 | Updated October 2024, 5 minutes ago.
The Ratio Transformer is a remarkable device. They can be made very precise, have a long longevity, and if left undamaged will perform as an AC Divider admirably!
Gertsch made a line of these transformers for decades and they were understandably pricey. But, if you carefully shop the surplus markets and Ebay, you can find them quite reasonable in price. This RT60 is a 5 decade unit. Given a 10v AC standard reference in (meaning as close as you can get to 10v AC) you can use those decades to divide the AC voltage over a range from 10V AC down to .0001v AC, via the dials. There are only a few caveats: the voltage input into this unit must not exceed .35xfrequency, and the frequency should remain between 10Hz and 10Khz (under 3Khz for maximum accuracy).
In the video, I provide 10v RMS 1Khz from a Fluke 510 AC Reference Standard, and I use the dials to divide the voltage down from 10.0000 v to .0001 v one decade step at a time (5x 10 steps = 50). The results are tablulated, and viewed in the video. With 5 decades of division, my lowest decade would be in 1/10 ths of a millivolt. So, I rounded anything reading lower than that to the nearest millivolt. The results are impressive with errors running from 0% to a max of .024%!
The Ratio Transformer is a remarkable device. They can be made very precise, have a long longevity, and if left undamaged will perform as an AC Divider admirably!
Gertsch made a line of these transformers for decades and they were understandably pricey. But, if you carefully shop the surplus markets and Ebay, you can find them quite reasonable in price. This RT60 is a 5 decade unit. Given a 10v AC standard reference in (meaning as close as you can get to 10v AC) you can use those decades to divide the AC voltage over a range from 10V AC down to .0001v AC, via the dials. There are only a few caveats: the voltage input into this unit must not exceed .35xfrequency, and the frequency should remain between 10Hz and 10Khz (under 3Khz for maximum accuracy).
In the video, I provide 10v RMS 1Khz from a Fluke 510 AC Reference Standard, and I use the dials to divide the voltage down from 10.0000 v to .0001 v one decade step at a time (5x 10 steps = 50). The results are tablulated, and viewed in the video. With 5 decades of division, my lowest decade would be in 1/10 ths of a millivolt. So, I rounded anything reading lower than that to the nearest millivolt. The results are impressive with errors running from 0% to a max of .024%!
