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## [TowerTalk] Autek RF-1

 To: [TowerTalk] Autek RF-1 alsopb@vance.net (alsopb@vance.net) Fri, 16 May 1997 07:33:32 -0500
 G3>According to QST for September 1996, the recent version of the Autek G3>instruction manual gives a formula on Page 10 for determining R +/- jX, G3>which isn't in my older manual. G3>Please could somebody let me know the details? G3>73 from Ian G3SEK Editor, 'The VHF/UHF DX Book' G3> 'In Practice' columnist for RadCom (RSGB) G3>-- G3>FAQ on WWW: http://www.contesting.com/towertalkfaq.html G3>Submissions: towertalk@contesting.com G3>Administrative requests: towertalk-REQUEST@contesting.com G3>Problems: owner-towertalk@contesting.com Dear Ian, Attached is a BASIC program implementing the formula. It has some problems. One doesn't always know if the reactance is capacitive or inductive. It does calculate the correct value as far as I can tell. You can always determine if the reactance is capacitive or reactive by sweeping the frequency and seeing if you are above or below resonance as determined by minimum Z. If you are above the resonance frequency it is inductive (+X) and - X if you are below -- assuming resonace isn't too far from your freq of measurement and there are no traps/lumped constants in the ant. 5 CLS 10 INPUT "Z=",Z 20 INPUT"SWR=",SWR 30 R =(2500+Z*Z)*SWR/(50*(SWR*SWR+1)) 40 IF Z >R THEN X=SQR(Z*Z R*R) ELSE X=SQR(R*R Z*Z) 50 PRINT "Z=";Z 60 PRINT "SWR=";SWR 70 PRINT "R=";R 80 PRINT "X=";X 90 INPUT X\$ 100 GOTO 5 73 de Brian/K3KO to: INT:G3SEK@ifwtech.demon.co.uk cc: INT:TOWERTALK@CONTESTING.COM Vance Net Inc End Of Message -- FAQ on WWW: http://www.contesting.com/towertalkfaq.html Submissions: towertalk@contesting.com Administrative requests: towertalk-REQUEST@contesting.com Problems: owner-towertalk@contesting.com
 Current Thread [TowerTalk] Autek RF-1, Ian White, G3SEK [TowerTalk] Autek RF-1, L. B. Cebik [TowerTalk] Autek RF-1, Ian White, G3SEK [TowerTalk] Autek RF-1, Paul Ferguson [TowerTalk] Autek RF-1, alsopb@vance.net <= [TowerTalk] Autek RF-1, Pete Soper [TowerTalk] Autek RF-1, Tom Wagner