VK5DJ's YAGI CALCULATOR

Yagi design frequency =432,80 MHz
Wavelength =693 mm
Elements contacting a metal boom 15,00 mm in diam.
Director/reflector diam =6,00 mm
Radiator diam =10,00 mm

ELEMENT LENGTHS AND SPACING
Reflector
343 mm long at boom position = 30 mm

Radiator
Single dipole 320 mm tip to tip at boom posn =169 mm
Folded dipole 327 mm tip to tip at boom posn =169 mm

Dir	Length	Spaced	Boom position	Gain	Gain
(no.)	( mm )	( mm )	( mm )		(dBd)	(dBi)
1	302	52	220		5,3	7,4
2	299	125	345		6,8	8,9
3	296	149	494		8,0	10,2
4	292	173	667		9,0	11,2
5	290	194	861		9,9	12,0
6	287	208	1069		10,6	12,8
7	284	218	1287		11,3	13,4
8	282	229	1516		11,8	14,0
9	280	239	1755		12,3	14,5
10	278	249	2004		12,8	14,9
11	276	260	2264		13,2	15,3

Director spacings are measured from the previous element
Tolerance for element lengths is +/- 2 mm

Boom position is the mounting point for each element as measured
from the rear of the boom and includes the 30 mm overhang.The total boom length is 2294 mm including two overhangs

The beam's estimated 3dB bandwidth is 35 deg

A half wave 4:1 balun uses 0,66 velocity factor RG-58C (PE)  and is 229 mm long plus leads

Here are some construction details for a folded dipole

Measurements are taken from the inside of bends
Folded dipole length measured tip to tip = 327mm
Total rod length =694mm
Centre of rod=347mm
Distance HI=GF=141mm
Distance HA=GE=172mm
Distance HB=GD=204mm
Distance HC=GC=347mm
Gap at HG=5mm
Bend diameter BI=DF=40mm

If the dipole is considered as a flat plane (see ARRL Antenna Handbook) then its resonant frequency is 432,8MHz and K is 0,900