HP 16340A RC calibration box for electrometers

Teardown and construction

Performance as received

Stock measurements:

Nominal resistance Measured results TCR Reference
100 Ω +4910 ppm, Log, 100.4910 Ω -4.2 ppm/°C KS3458A REF2
1 kΩ +370 ppm, Log, 1000.370 Ω +1.7 ppm/°C KS3458A REF2
10 kΩ -86.2 ppm, Log, 9999.138 Ω +8.1 ppm/°C KS3458A REF2
100 kΩ -29.5 ppm, Log, 99.99705 kΩ +7.6 ppm/°C KS3458A REF2
1 MΩ -325 ppm, Log, 0.999675 MΩ -4.5 ppm/°C KS3458A REF2
10 MΩ KDI Pyrofilm PME70, ±50 ppm/K, 700V +1306 ppm, Log, 10.013064 MΩ +15 ppm/°C KS3458A REF2
100 MΩ E&C RH1HVS ±200 ppm/K +350 ppm, Log, 100.03500 MΩ +57 ppm/°C KS3458A REF2
1 GΩ E&C RH1HVS ±200 ppm/K +368.6 ppm, Log, 1.003686 GΩ +100 ppm/°C KS B2987A 20V
10 GΩ E&C RH1HVS ±200 ppm/K -4369 ppm, Log, 9.956312 GΩ +141 ppm/°C KS B2987A 100V
100 GΩ E&C RH3HVS ±200 ppm/K -4668 ppm, Log, 99.53319 GΩ +164 ppm/°C KS B2987A 100V

Upgrade for RC box with high stability resistors

Based on test results, we can see okay performance of 1kΩ value output, but mediocre results by modern standards for anything else, especially the most interesting resistances over 10 MΩ.

To improve performance and stability of the this RC box for metrology applications, we will replace all resistors with much better parts.

Welcome new resistors, better ones that money can buy.

New performance results with upgraded resistors

Nominal resistance New resistor spec Measured results TCR Reference Price per 1 pcs
100 Ω VPG VHP102K 100 Ω TC P0.6 Log, Ω +0.59 ppm/°C KS3458A REF2 $46
1 kΩ VPG VHP203T 1 kΩ, TC N0.4 Log, Ω -0.38 ppm/°C KS3458A REF2 $50
10 kΩ VPG VHP101T 9.998 kΩ 0.1% Log, Ω TBD ppm/°C KS3458A REF2 $70
100 kΩ VPG VHA518 100 kΩ 0.005% Log, kΩ -0.51 ppm/°C KS3458A REF2 $350
1 MΩ VPG VHA518-11Z 1 MΩ 0.01%, ±2.2 ppm/°C, 600V Log, MΩ +0.19 ppm/°C KS3458A REF2 $270, Y17591M00000T2L 2014
10 MΩ Caddok USF340 10 MΩ TC5 0.1%, 300V Log, MΩ +3.4 ppm/°C KS3458A REF2 $15
100 MΩ NICROM 90.3 ± 25 ppm/°C, 1kV+ Log, MΩ TBD ppm/°C KS3458A REF2 $13
1 GΩ NICROM 90.3 ± 25 ppm/°C, 1kV+ Log, GΩ TBD ppm/°C KS B2987A 20V $13
10 GΩ NICROM 100.4 ± 25 ppm/°C, 1kV+ Log, 9.993265 GΩ TBD ppm/°C KS B2987A 100V $22
100 GΩ NICROM 400.2 ± 25 ppm/°C, , 1kV+ Log, GΩ TBD ppm/°C KS B2987A 100V $72
Author: Illya Tsemenko
Published: July 24, 2020, 7:10 a.m.
Modified: Aug. 23, 2020, 2:54 p.m.

Comments