wrote:

dxAce wrote:
dxAce Apr 17, 3:11 pm show options
Newsgroups: rec.radio.shortwave
From: dxAce - Find messages by this author
Date: Sun, 17 Apr 2005 18:11:26 -0400
Local: Sun,Apr 17 2005 3:11 pm
Subject: splitter ?
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Yes, the calibration may indeed be off with various manufacturers,
however all things being equal it should be very easy to determine
various antenna changes with a 'particular' receiver.

Damn simple.

dxAce
Michigan
USA
---------------------------
Sadly very few radios have S-meters that behave in a "correct" way.
I have a HP calibrated step attenuator, with .5dB steps. Zin 50Ohm
Zout 50 Ohm. When checked at the electronics lab (at UK) the
error was less then .07dB worst case. I have a simple crystal osc that
is very temp stable. Zout 50 Ohms at .1V. Measured to be 0.10V.

I have had chance to check quite a few receivers. From the famous
R390, to one of the Lowe 150s. I would have to dig out my notes, if
I even still have them, and the R390 was the ony one that tracked
6dB/1S unit.

This url has better data then I can dig out out the moment:
http://www.ac6v.com/sunit.htm

Unless you know, that is have measured, your S-meter, it is only
a rough indication.

Yes, of course. (No ****, Sherlock)

You can clearly use your S meter to compare one antenna to another,
but I would be very hesitant to say that "antenna 1 is S2 and antenna
2 is S6, therefore antenna 2 has 24dB more gain then antenna 1."

No one was trying to say that.

Based on the assumption that 1 S unit equals 6 dB.
S6-S2=4 S-units, 4 X6dB = 24dB
(Math shown for those new to the hobby)

Now if you have a calibrated step attenuator you could show that:
Ant 1 gives S2
Ant 2 requires 20dB of attenuation to give a reading of S2.
Ant 2 has about 20dB more gain then Ant 1.

I bought my Hp attenuator at a surplus store for $5.
I bought 2 fox industries 50P-077 +12V BCD attenuators
that have a measured error of less then .01dB for $1each!
Coupled with some Pasternak PE7101 coaxial relays I hope
to be able to some "meaningfull" antenna experiments this
summer and next winter.

There is a vacant lot caty corner behind us and I have permission
from the lot owner, and both my rear and next door neigbors to run
an temp antenna to and across that lot. I will be able to get about
300' of wire up in a straight line. I intend to see just how length
effect
signal strength.

Next fall a frined is going to let me spend a few weekends on his
fields to check even longer wires.

Yes.. but you wasted most of the space above to say nothing.

Boggling to say the least...

I'm more and more amazed here everyday.

Continue to tote.

dxAce
Michigan
USA

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************************

thanks to one and all for some great info.
i need to study on this. i found an old article
in the july/04, NASWA Journal. get my facts together
here, and move to there. would be fun to build when
i find the time. thanks again...
Drifter...

On Mon, 18 Apr 2005 00:12:32 GMT, Drifter wrote:

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************************

thanks to one and all for some great info.
i need to study on this. i found an old article
in the july/04, NASWA Journal. get my facts together
here, and move to there. would be fun to build when
i find the time. thanks again...
Drifter...


Now that the dust has settled a little bit and the belligerents are
hopefully being triaged.....

Please read the spec sheets on the prospective splitter you intend on
using or, if rolling your own, look at the design. Many splitters
claim to have "only" a 3 or 5 dB loss, but that's only "best case."
Often times, the loss will vary greatly across the operating range of
the splitter (and sometimes the impedance!). For HF and MF, the
losses are usually not too bad.

If you plan to use a preamplifier, PLEASE (!) use a low noise model.
Often times preamps will raise the noise floor by several dB, which
could wipe out some weak DX for you. Purchase (or build) the BEST
preampllifier that you can. It should be low noise, and the gain
should not be so high that it goes into oscillation (you really just
want to overcome the splitter losses). Some preamps will cause
trouble with the 3d order intercept points of your receiver by
overloading the front end. Every active component plays against
every other active component, so be mindful of your trade-offs and
gains.

Good luck!

Al in CNMI

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In article ,
Tebojockey wrote:

On Mon, 18 Apr 2005 00:12:32 GMT, Drifter wrote:

- Hide quoted text -
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************************

thanks to one and all for some great info.
i need to study on this. i found an old article
in the july/04, NASWA Journal. get my facts together
here, and move to there. would be fun to build when
i find the time. thanks again...
Drifter...


Now that the dust has settled a little bit and the belligerents are
hopefully being triaged.....

Not a chance! I have to give you a hard time.

Please read the spec sheets on the prospective splitter you intend on
using or, if rolling your own, look at the design. Many splitters
claim to have "only" a 3 or 5 dB loss, but that's only "best case."
Often times, the loss will vary greatly across the operating range of
the splitter (and sometimes the impedance!). For HF and MF, the
losses are usually not too bad.

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
Ventura, California

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
----------------------------------------------------------------

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

In article . com,
wrote:

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
----------------------------------------------------------------

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.

Some of the information you posted above is wrong. Please read my post
at the top.

It does not matter if the passive splitter is resistive or a coupled
transformer type the power divides in half otherwise you will violate
the laws of conservation.

The transformer type will provide some isolation between the ports above
what the resistive splitter will provide but that's about it.

Sorry that just the way it is as you don't get something for nothing in
this world.

--
Telamon
Ventura, California

Here's a website for making a transformer type HF splitter.

http://www.geocities.com/n2uhc_2/hfsplitter.html

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On Wed, 20 Apr 2005 02:38:40 GMT, Telamon
wrote:

In article ,
Tebojockey wrote:

On Mon, 18 Apr 2005 00:12:32 GMT, Drifter wrote:

- Hide quoted text -
- Show quoted text -
************************

thanks to one and all for some great info.
i need to study on this. i found an old article
in the july/04, NASWA Journal. get my facts together
here, and move to there. would be fun to build when
i find the time. thanks again...
Drifter...


Now that the dust has settled a little bit and the belligerents are
hopefully being triaged.....

Not a chance! I have to give you a hard time.

You don't. One-upmanship has no place here.


Please read the spec sheets on the prospective splitter you intend on
using or, if rolling your own, look at the design. Many splitters
claim to have "only" a 3 or 5 dB loss, but that's only "best case."
Often times, the loss will vary greatly across the operating range of
the splitter (and sometimes the impedance!). For HF and MF, the
losses are usually not too bad.

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...



You are arguing points that I did not even discuss. What you are
describing is the standard "Wilkinson" splitter or combiner. We could
also discuss 90 degree splitters and other variants, but that would be
beyond the ascope of what I was trying to impart to the person I was
trying to help.

Your assertion that they may be active or passive is correct. Loss
implies a passive splitter (be it resistive or reactive), while the
other part of my dissertation (as far as raising the noise floor,
etc.) implies an active splitter. Perhaps it was not clear to you,
but perhaps the person who it was posted for understood what I was
saying.

I should have also given him information on port to port isolation as
well as the effect upon his 3d order intercept points that active
splitters can cause, but I didn't feel it would benefit him.

My intent was to be as layman as possible to assist the person asking
the question.


Al in CNMI

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In article ,
Tebojockey wrote:

On Wed, 20 Apr 2005 02:38:40 GMT, Telamon
wrote:

In article ,
Tebojockey wrote:

On Mon, 18 Apr 2005 00:12:32 GMT, Drifter wrote:

- Hide quoted text - - Show quoted text -
************************

thanks to one and all for some great info. i need to study on
this. i found an old article in the july/04, NASWA Journal. get
my facts together here, and move to there. would be fun to build
when i find the time. thanks again... Drifter...


Now that the dust has settled a little bit and the belligerents
are hopefully being triaged.....

Not a chance! I have to give you a hard time.

You don't. One-upmanship has no place here.

You have no sense of humor.


Please read the spec sheets on the prospective splitter you intend
on using or, if rolling your own, look at the design. Many
splitters claim to have "only" a 3 or 5 dB loss, but that's only
"best case." Often times, the loss will vary greatly across the
operating range of the splitter (and sometimes the impedance!).
For HF and MF, the losses are usually not too bad.

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...



You are arguing points that I did not even discuss.

That happens on Usenet when more than 2 people participate in a
discussion.

What you are describing is the standard "Wilkinson" splitter or
combiner. We could also discuss 90 degree splitters and other
variants, but that would be beyond the ascope of what I was trying to
impart to the person I was trying to help.

Sorry I messed up your message.

Your assertion that they may be active or passive is correct. Loss
implies a passive splitter (be it resistive or reactive), while the
other part of my dissertation (as far as raising the noise floor,
etc.) implies an active splitter. Perhaps it was not clear to you,
but perhaps the person who it was posted for understood what I was
saying.

I should have also given him information on port to port isolation as
well as the effect upon his 3d order intercept points that active
splitters can cause, but I didn't feel it would benefit him.

My intent was to be as layman as possible to assist the person asking
the question.

Yeah, it's a balancing act all right.

--
Telamon
Ventura, California

On Tue, 26 Apr 2005 06:09:00 GMT, Telamon
wrote:

In article ,
Tebojockey wrote:

On Wed, 20 Apr 2005 02:38:40 GMT, Telamon
wrote:

In article ,
Tebojockey wrote:

On Mon, 18 Apr 2005 00:12:32 GMT, Drifter wrote:

- Hide quoted text - - Show quoted text -
************************

thanks to one and all for some great info. i need to study on
this. i found an old article in the july/04, NASWA Journal. get
my facts together here, and move to there. would be fun to build
when i find the time. thanks again... Drifter...


Now that the dust has settled a little bit and the belligerents
are hopefully being triaged.....

Not a chance! I have to give you a hard time.

You don't. One-upmanship has no place here.

You have no sense of humor.

Well, yeah I do...maybe I overreacted to your post.



Please read the spec sheets on the prospective splitter you intend
on using or, if rolling your own, look at the design. Many
splitters claim to have "only" a 3 or 5 dB loss, but that's only
"best case." Often times, the loss will vary greatly across the
operating range of the splitter (and sometimes the impedance!).
For HF and MF, the losses are usually not too bad.

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...



You are arguing points that I did not even discuss.

That happens on Usenet when more than 2 people participate in a
discussion.

Been on Usenet a long, long time. You're right there!


What you are describing is the standard "Wilkinson" splitter or
combiner. We could also discuss 90 degree splitters and other
variants, but that would be beyond the ascope of what I was trying to
impart to the person I was trying to help.

Sorry I messed up your message.

"Fuhgeddaboutit" (I do a lousy Sopranos imitation).


Your assertion that they may be active or passive is correct. Loss
implies a passive splitter (be it resistive or reactive), while the
other part of my dissertation (as far as raising the noise floor,
etc.) implies an active splitter. Perhaps it was not clear to you,
but perhaps the person who it was posted for understood what I was
saying.

I should have also given him information on port to port isolation as
well as the effect upon his 3d order intercept points that active
splitters can cause, but I didn't feel it would benefit him.

My intent was to be as layman as possible to assist the person asking
the question.

Yeah, it's a balancing act all right.

And when I drink too much I list badly to port..... LOL

Al in CNMI


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