On Apr 19, 7:38 pm Telamon wrote:
Snip

There are passive and there are active splitters.

Passive can be transformer or resistive it does not matter. If the
splitter is one port to two ports then the power is going to divided in
half between the two output ports. It is that simple. Half the power is
3dB and half the voltage is 6 dB. That's all there is to it.

Active splitters can be anything because you can have any amount of
amplification to to make up for the division in power.

Same story with one to four ports where the power out is 1/4 the power
in. Same story with any other division splitter.

Now if you force me to I WILL resort to an analogy where you have this
bushel of apples you want to divide in half and...

--
Telamon
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Please review the information at:
http://www.microwaves101.com/encyclo..._splitters.cfm

And note that a resistive splitter has:

"Resistive power dividers are easy to understand, can be made very
compact,
and are naturally wideband, working down to zero frequency (DC). Their
down
side is that a two-way resistive splitter suffers 3 dB of real
resistive loss, as
opposed to a lossless splitter like a hybrid. Accounting for the 3 dB
real loss
and the 3 dB power split, the net power transfer loss you will observe
from the
input to one of the two outputs is 6.04 dB for a two-way resistive
splitter.
(Thanks, Dr. BKS, for helping us clarify that point!)"

I own a Mini Circuits ZFSC-2-.
It has a measured insertion loss of less then 3.5dB for 100KHz through
30MHz

Another strength of tranformer based hybrids/power splitters is the
greater
isolation between power out ports.

The Mini circuits ZFSC-2-1is rated for:
5 MHz 25dB isolation
midband (~450MHz) 20dB isolation
500MHz 20 isolation
These are minimum not typ[ical.

My unit has been measued to have better then 25dB isolation
between the power out ports from ~250KHz to above 30MHz.
The isolation start to creep up below 250KHZ reaching
a minimum of ~21dB at 100KHz.
Below 100KHz the loss starts increasing and by 10KHZ the
loss is just over 9dB and the isolation is down to just less then 15dB.

The "roll your own splitter" page gives some real world loss and
isolation data:
http://www.dxing.info/equipment/roll...own_bryant.pdf

MiniCircuits isloation PDF
http://www.minicircuits.com/appnote/pwr2-4.pdf

MiniCircuits hybrid/power splitter PDF
http://www.minicircuits.com/appnote/psc2-2.pdf

Quoting again frm the article on resistive splitters:
"To put it simply, the resistive splitter has double the dBs compared
to a lossless
splitter's insertion loss. Thus a two-way resistive splitter transfers
-6.04 dB power to
each arm, a three-way splitter transfers -9.44 dB, a four-way transfers
-12.08 db, etc."

And:
"The isolation of a resistive splitter is equal to its insertion loss."

I hope that we can all agree that 3.5 dB loss is much better then 6dB
loss and that 20dB
isolation is better then 12dB isolation. I ued the wort case bad specs
from minicircuits for loss
and isolation.

In the microwave world resitive splitters are the rule. In HF/VHF/UFH
transformer splitters appear
to dominate.

Sorry for the dublicate posting under two threads.
I feel this is a very important concept and wanted to make sure
my position is clear.

Terry