Quick Mixed Calculations

Question 1

Total loss from -10 dBm Tx, -25 dBm Rx.

Answer 1

Budget 15 dB.

Question 2

Alien crosstalk margin for 10G.

Answer 2

PSANEXT >0 dB.

Question 3

Horizontal length max copper.

Answer 3

90m permanent +10m patches =100m channel.

Question 4

Support spacing J-hooks.

Answer 4

1.5m max.

Question 5

Conduit fill 1 cable.

Answer 5

53%.

Question 6

2 cables.

Answer 6

31%.

Question 7

Fiber splice loss max.

Answer 7

0.3 dB.

Question 8

Connector loss max.

Answer 8

0.75 dB.

Question 9

Pull tension fiber typical.

Answer 9

600 N max for armored.

Question 10

Bend radius fiber loaded.

Answer 10

10-15x OD.

Question 11

PoE 802.3af max.

Answer 11

15.4W source.

Question 12

802.3at.

Answer 12

30W.

Question 13

Cat6 atten @100m 100MHz approx.

Answer 13

~20 dB.

Question 14

NEXT Cat6 min.

Answer 14

~44 dB.

Question 15

Length from capacitance (if tester uses).

Answer 15

Varies, but similar to TDR.

Question 16

dB margin min recommended.

Answer 16

3 dB fiber.

Question 17

Bundle size max no derate.

Answer 17

~24 cables.

Question 18

Velocity factor Cate.

Answer 18

~0.69c.

Question 19

Impedance UTP,

Answer 19

100 S.

Question 20

Exam calc tip: Always show units and steps.

Answer 20

Master these calculations-they’re key for passing! Use the visuals to memorize formulas/charts. If you need answers varied, more examples, or a mock calc quiz, let me know. You’re ready to ace the 631A!