Hello Rob.
29 Oct 97 22:05, Rob Dennis wrote to Jeff Edmonson:
RD>
>>> RD> ROY! Re-post please...
>>> Ummmmmmmmmmm, now I wonder if Roy didn't netmailed me
>>> that missing part. CRS is taking its toll at this
>>> age.
JE>> Just saw it. Let me know if you need it.
RD>
RD> From the wrong series Jeff.
RD> The part I need is from the LPDA posting,part # 4.
LPDA or LPDS series? I've got them all, just let me know which one it is
that you need. Antenna type and for what band..
=== Begin LPA4.ANT ===
Ä Ham (Amateur) Radio TECHnology Conference (1:202/909.10) ÄÄÄÄÄÄÄÄÄÄ
HAM_TECH Msg : #578 [26] From : Wayne Sarosi
1:374/73.2 21 Apr 97 20:12:01 To : All
22 Apr 97 00:53:18 Subj : LPAs-4
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Ä LPA Series - 141-149 MHz (2m + MARS/CAP)
USE: Amateur Band 2m and MARS/CAP Frequencies
Note: See ARRL Antenna Handbook under LPA construction
Tau = 0.965
Sigma = 0.181
B = 1.0567
COT alpha = 20.686
BAR = 1.295
Bs = 1.368
Lambda max = 6.9787-ft
Lb = [0.25(1-(1/Bs))COT alpha)Lambda max] = 9.71-ft
N = 1 + (log Bs / log (1/Tau)) = 10
The following are in inches, two of each required (L)
-+----------------------------
L1 = 21.84 d1,2 = 15.163
L2 = 21.10 d2,3 = 14.632
L3 = 20.40 d3,4 = 14.120
L4 = 19.71 d4,5 = 13.626
L5 = 19.06 d5,6 = 13.149
L6 = 18.42 d6,7 = 12.689
L7 = 17.81 d7,8 = 12.245
L8 = 17.22 d8,9 = 11.816
L9 = 16.65 d9,10 = 11.402
L10 = 16.09
Zt =10.468 Sigma' = Sigma/sqrt Tau = 0.18425
Ro = 50
Zav = 265.66
Zo = Ro^2/(8(Sigma'(Zav))) + Ro(Sqrt(Ro/(8(Sigma'(Zav))) + 1) = 57.0428
Gain = 10.5 dBi
S can be calculated from the ARRL Antenna Handbook, but is 0.804 for
0.25-in elements and 1-in booms.
Next is the 6m LPA. Element attachment will be after the 6m
posting. SEE BELOW!!!!
*************************************************************
* NOTE: The boom on all these LPAs is 1-inch diameter. *
* All elements have a 0.9-in adjustment in the length *
* to compensate. Sorry about that. The Freq file will *
* have the proper statement put in. *
*************************************************************
-WS
---------------
* Origin: KB4YLY, Moderator (1:374/73.2)
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