Components for building calibration loads
Resistors
50-ohm Load (2x 100-ohm in parallel) and 100-ohm Load
Specification:
Composition: thin-film
Resistance: 100-ohm
Tolerance: +-0.1%
Temperature coefficient: +-25ppm/ºC
Package: 0603
Examples:
200-ohm Load
Specification:
Composition: thin-film
Resistance: 200-ohm
Tolerance: +-0.1%
Temperature coefficient: +-25ppm/ºC
Package: 0603
Examples:
eBay: 200 OHM 0.1% 0603 25ppm Resistor RN731JTTD2000B25 KOA NEW Qty:100pcs
Note: could be used as well for the 50-ohm load (x4 in parallel) and the 100-ohm load (x2 in parallel)
Assembly examples
Notes:
50-ohm, 100-ohm and 200-ohm loads shown above were manufactured with 200-ohm resistors
The center pin of the connectors was trimmed down
100-ohm and 200-ohm loads are not required for calibration
Useful links about building calibration loads
http://blog.kotarak.net/2009/10/n2pk-vna-calibration-standards.html
http://blog.kotarak.net/2010/04/n2pk-vna-sma-calibration-standard.html
http://www.qsl.net/in3otd/electronics/VNA_calkit/calkit.html