Minimum Loss Pads

For Matching Two Impedances where Z1 > Z2 Matched, use a resistor , RL in series with the smaller
impedance such that
If the smaller impedance only is to be matched, use a
resistor RS in shunt across the larger impedance such that
Where Only One Impedance is to be Matched
If the larger impedance only is to be Here also

Tables of R1 and R 2 Values

When Z1 is 600 ohms
and Z2 is less than 600 ohms.

Z2 500 400 300 250 200 150 100 75 50 40 30 25
R1 245 346 424 458 490 520 548 561 575 580 585 587
R2 1,225 694 425 328 245 173 110 80.2 52.2 41.4 30.8 25.6
db
Loss
3.8 5.7 7.6 8.7 10.0 11.4 13.4 14.8 16.6 17.6 18.9 19.7

When Z2 is less than 25 ohms,


and      R2 = Z2         
Where Z2 is 600 ohms
and Z1 is greater than 600 ohms.

Z1 800 1,000 1,200 1,500 2,000 2,500 3,000 3,500 4,000 5,000 6,000 8,000 10,000
R1 400 632 849 1,162 1,673 2,180 2,683 3,186 3,688 4,690 5,692 7,694 9,695
R2 1,200 949 849 775 717 688 671 659 651 638 633 624 619
db
Loss
4.8 6.5 7.6 9.0 10.5 11.6 12.5 13.3 13.9 15.0 15.8 17.1 18.1

When Z1 is greater than 10,000 ohms,

let  R1 = Z 1 – 300
and  R1 = 600