Download presentation

1
**RF IMPEDANCE TRANSFORMATION**

(WHAT THE BOOKS NEVER TELL YOU) By Forest Cummings, W5LQU And Dave Russell, W2DMR

2
**Transforming Transforming with a transformer Turns ratio = 1 : 3 50**

450 Impedance ratio = 1 : 9 Transforming with a transformer

3
DEFINITION OF Q Xs Rp Xp Rs Q = Xs/Rs Q = Rp/Xp

4
**Rp/Rs = Q2 + 1 SERIES = PARALLEL Rs + jXs = Rp(jXp) / (Rp + jXp) |**

ALGEBRA | Rp/Rs = Q2 + 1

5
**MATCH 250 TO 50 Xs -100 Xp Rp 250 Rs -125 50 Q = 2 Q2 + 1 = 250/50 = 5**

6
**THE R-X PLANE 200 150 100 +j 50 XL ohms R ohms 100 150 200 XC ohms 50**

R ohms 100 150 200 XC ohms 50 -50 -j -100 -150 -200

7
**SERIES IMPEDANCE 150 100 50+j50 50 Z=70.7 A=45 deg Tan A=Q=1 Z XL A R**

R B 50 100 150 200 250 XC -50 Z 150-j100 -100 Z=180 B= TanB=Q=0.67 -150

8
**PARALLEL IMPEDANCE //XL //XC R = 250 ohms 150 100 50 XL R 50 100 150**

R 50 100 150 200 250 300 XC -50 //XC -100 R = 250 ohms -150

9
**SERIES = PARALLEL 250 to 50 Match**

200 150 100 50 XL R 50 XC 100 150 200 250 300 -50 -100 -125 -150 (50-j100) = 250 // -j125 SERIES = PARALLEL -200

10
**THE L NETWORK XL = 100 XL = 100 Xs -100 Rp 50 50 Xc Rs 250 -125 50**

Equivalent series circuit L network matching 250 ohms to 50 ohms Note: Series XL NOT equal to shunt Xc

11
**MATCH 10 TO 50 Xs -20 Xp -25 Rp 50 Rs 10 Q = 2 Xp =50/2= -25**

12
**ANOTHER L NETWORK Xc = -20 Xp -25 XL 25 Rp 50 XL 25 Rs 50 10**

L network matching 10 ohms to 50 ohms Equivalent parallel circuit NOTE: Shunt XL NOT equal to series Xc

13
**THE Tee NETWORK (TWO L NETWORKS)**

XL1 = 150 XL2 = 200 Q1 Q2 Rin 50 R 500 XC1 -167 XC2 -250 RL 100 Q12+1=500/50=10 Q1 = 3 XC1 = 500/3 = -167 XL1 = 50(3) = 150 Q22+1=500/100=5 Q2 = 2 XC2 = 500/2= -250 XL2 = 100(2) = 200

14
**THE Tee NETWORK (CONTINUED)**

1224vp, 8A XL1 = 150 XL2 = 200 100w, 316vp, 2A Rin 50 XC -100 RL 100

15
**THE PI NETWORK ALSO TWO L NETWORKS**

XL1 = 166 XL2 = 22 Q1 Q2 Rin 2000 Rs 13.8 RL 50 XC2 -31 XC1 -167 Q1 = 12, Q12+1 = 145 Rs = 2000/145 = 13.8 XC1 = 2000/12 = -167 XL1 = 13.8(12) = 166 Q = 50/13.8 = 3.62 Q2 = SQR(2.62) = 1.6 XL2 = 13.8(1.6) = 22 XC2 = 50/1.6 = -31

16
**THE PI NETWORK (CONTINUED)**

XL = = 188 Q2 Q1 Rin 2000 RL 50 Rs 13.8 XC2 -31 XC1 -167 Q12+1 = 145 Q1 = 12 Q = 3.62 Q2 = 1.6

17
JUST REMEMBER THIS ! Rp/Rs = Q2 + 1

18
**SIMPLE ANTENNA COUPLER**

TUNES 40M – 10M 45 FOOT LONG WIRE 10 uH 50 500 pF GROUND

Similar presentations

OK

Superposition, Thevenin / Norton Equivalents, Maximum Power Transfer Circuits 1 Fall 2005 Harding University Jonathan White.

Superposition, Thevenin / Norton Equivalents, Maximum Power Transfer Circuits 1 Fall 2005 Harding University Jonathan White.

© 2018 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google

Ppt on duty roster template Ppt on aircraft emergencies Ppt on changes around us for grade 6 Ppt on viruses and bacteria differences Ppt on cell the fundamental unit of life Ppt on water our life line screening Ppt on new product design Ppt on partnership act 1932 rules Free ppt on cost accounting Ppt on event driven programming pdf