Subj : 70cm 19el Tonna Yagi info
To   : WW
From : G8MNY
Date : Wed Aug 21 2019 10:04 am

G8MNY    TECHNI   21.08.19 04:30l 56 Lines 1648 Bytes #180 (0) @ WW
BID : 18346_GB7CIP
Subj: 70cm 19el Tonna Yagi info
Path: OK0NBR OK2PEN N3HYM GB7CIP
Sent: 190821/0728Z @:GB7CIP.#32.GBR.EURO #:18346 [Caterham Surrey GBR]
From: G8MNY@GB7CIP.#32.GBR.EURO
To  : TECH@WW

               Length   Measured
Element         in mm   Spacing

Reflector        350
Folded Dipole           Not done
Director 1       330    Not done
Director 2       315    Not done
Director 3       305    Not done
Director 4       300    Not done
Director 5       297    Not done
Director 6       295    Not done
Director 7       295    Not done
Director 8       290    Not done
Director 9       285    Not done
Centre of boom
Director 10      285    171
Director 11      280    172
Director 12      280    173
Director 13      275    172
Director 14      275    172
Director 15      270    172
Director 16      270    172
Director 17      265    173

Quoted figures
Gain 17dBi

Aperture -3dB      H 2x14ø
   "               V 2x16ø
Front-back         23dB
Side Lobes           38dB
VSWR               ò 1.2
Weight             1.1kg
Length             3.2m
Wind load @ 25m/S  5.4kg

                     73 de Andy G0FTD @ GB7SXE.#38.GBR.EU
------------------------------------------------------------------------------
Folded dipole spacing 2-3cm.
I have found a problems with Tonners of this construction, the ally-ally
connections inside the moulded connection block. These corrode & you end up
with no aerial. Repairs can be done by sawing away at the block until the
connection rivet is located. Drill this out & drill & tap in a suitable brass
screw after first painting it with silver conductive paint on the screw &
tapped hole. Make a paper/tape mould around block & fill in the hole you made
with a car repair resin.


Why Don't U send an interesting bul?


--- Mystic BBS v1.12 A43 (Linux/32)
 * Origin: HAMRADIO telnet slacko.kozow.com (21:5/101)

.