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2, 3 & 4-Port Power Dividers...
50 Ohm – Power Dividers
QST October 1973 pg 97
(with corrections of dimensional errors in original article)
|
Mhz |
Dimension A |
Dimension B |
Dimension A |
Dimension B |
|
144 |
41.00" |
42.25" |
1041.4mm |
1073.2mm |
|
220 |
26.84" |
28.09" |
681.7mm |
713.5mm |
|
432 |
13.67" |
14.92" |
347.2mm |
379.0mm |
|
902/903 |
6.54" |
7.79" |
166.1mm |
197.9mm |
|
1296 |
4.55" |
5.80" |
115.6mm |
147.3mm |
|
2304 |
2.56" |
3.81" |
65.0mm |
96.8mm |
Described here and in the accompanying drawings are two- and four-port power
dividers for 144-, 220-, and 432-Mhz bands designed by Don Hilliard,
W0EYE. Don stresses that the design information should be exactly followed
to prevent performance degrading. The two-port model uses a 1 inch square,
1/8 inch thick aluminum outer conductor and a 1/4 inch diameter round brass or
copper tube for the inner conductor. The four-port model uses the same
outer conductor as the two-port model, but the inner conductor uses a brass or
copper round tube, 11/32 inch O.D. All connectors are UG56A/U mounted in
5/8 inch holes with No. 4-40 screws, 1/4 inch long. Mounting screw holes
are drilled with a No. 43 drill, taped for the 4-40 thread. The ends
and solder access holes should be covered with 1 x 1 x 1/32 inch aluminum plates
held in place with RTV sealant after assembly is completed.
( I used JB WELD as a sealant, W7CQ )
The rf handling capacity of the power divider is limited by the type - N connectors,
but nevertheless is in excess of the legal amateur limits, being two kilowatts
or better at 432 MHz.
Bandwidth of the devices is more than sufficient to cover the entire band of the
design with less than 1.24 : 1 VSWR from
QST - October 1973 page 97
If you drill a hole through one side of the brass 1/4 center conductor, the
N connector shown below with a #14 copper wire extension will center the tube inside
the 1 inch square outer conductor. This makes soldering the center connector
much easier. W7CQ

Sometimes it is useful to have a three port splitter, like when putting up a 6-yagi antenna array.
Using the sams techniques described above, one might construct a spliter according to the drawing
below:

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