"Telamon" wrote in message
...
In article . com,
wrote:

Telamon wrote:

Remember to terminate all ports at all times or your results will
vary.

The transformer type of splitter will have a "U" shaped response
curve
so you need to be within that band for it to work right. The
resistive
type is good from DC to some max frequency and you need to be in that

range.

From the transmitter value each output port should be 3 dB down when
the
other output port is terminated in 50 ohms. The actual loss will be a

little larger then 3 dB by the splitters insertion loss.

Oh yeah, and your meter is probably a through type instead of a load
type so you need to put a 50 ohm load on the far side of the meter.

When you check each splitter also switch the meter and its load in
each
leg to see how balanced the splitter is in each output port.

Be sure to turn the transmitter off before all connections are made
or
you could damage your transmitter.

--
Telamon
Ventura, California

I made some measurements last night.
I decided to move from ~7MHz to 146 because 7MHz is just
too close to the lower limit on my mMc splitter.

I have an IC28A that is adjusted to give 1wt in low power.
I used a 10dB Narda 766-10 power attenuator in series with
the splitter input. I used another 766-10 attenuator in series
with the output and the sensor head on Boonton RF power meter.
I used a .5% 50 ohm terminator for the other port

The resitive splitter gave me 6dB of POWER loss.
The MC transformer based splitter gave me just over
3.2dB of loss.

I called a freshly frocked dual PHD, EE and physics, I know
and asked her what the heck is happening. The quick answer
is the resistive splitter is like any other resitive voltage
divider. The transformer unit is like a transformer step down,
or step up. The only losses in a transformer splitter are the
wire losses and the core loss. The R in the MiniCircuits dispates
no power if all ports are matched.

She invited me to "her" lab Friday afternoon and she will use
the modern equipment to verify my measurements.
She suggested that I treat the resistive network and use kichoff's
(?spelling?, it has been too long since college) law to show the
dissapation of each element. It is too late tonight and my head
hurts from this stuff.

Oh, and cctual S-meter measurements show the MC splitter has half
the loss of the resitive splitter.

On a good note, I picked up a 3 section "dB Products" heavy aluminium
mast and another MC splitter like mine and a 1 in 8 out RCA active
LF/HF
splitter rated for use from 100Kc to 40Mc. It used Nuvisters and
appears
to have selectable MB/BCB filters. No manual, and the only diagram is
stincyled on the inside of the lid. And no model number only an old
"Signal Corp" decal. My friend retired ATT microwave engineer and is
moving
to AZ because he is sick of the winter snow here. He has a storage
building full of such junk and I get to cherry pick it and haul it to
another friend.
I hope to check the RCA coupler before going to the university lab.
It would be nice to run a SN and frequency response.

Well, that's interesting results.

I've used resistive splitters in the past and have gotten the 6dB
division. The resistive splitters I have used in the past are the T and
the delta type. I usually work with scopes so I see 1/2 the voltage or
6dBV on the scope through the splitter and I have no explanation why
you are seeing more than that.

What is the make and model number of the resistive splitter?

--
Telamon
Ventura, California

I think you are both in violent agreement - 6dB loss means the output over
the input is 1/2 for voltage (constant impedance), 1/4 for power. A
resistive 2-way minimum loss splitter has 6dB loss; a transformer 2-way
splitter is 3dB.

Tom