UHF TV Y-splitter

[Dave Farrance]

Since y-splitters for UHF TV aerial leads were selling at £1.50 in a
local cut-price shop, I broke one open to see what's inside.

15kbyte JPEG:
http://anvil.pwp.blueyonder.co.uk/splitter.jpg

Doesn't that have a mismatched half-impedance input? Or am I
misunderstanding something, here?

Can anyone recommend a website that describes RF y-splitters and RF
combiners?

 

[Gary Tait]

Whereas On Thu, 23 Oct 2003 15:31:04 GMT, Dave Farrance

Since y-splitters for UHF TV aerial leads were selling at £1.50 in a
local cut-price shop, I broke one open to see what's inside.

15kbyte JPEG:
http://anvil.pwp.blueyonder.co.uk/splitter.jpg

Doesn't that have a mismatched half-impedance input? Or am I
misunderstanding something, here?

Can anyone recommend a website that describes RF y-splitters and RF
combiners?

You have the circuit drawiang incorrect. The one output is out of
phase with the other.

 

[Dave Farrance]

Whereas On Thu, 23 Oct 2003 15:31:04 GMT, Dave Farrance


You have the circuit drawiang incorrect. The one output is out of
phase with the other.

Not really. The core ensures that the current is evenly distributed
between the two outputs. The black dots on the circuit diagram show the
polarity of the windings, and that's how the core is wound.

 

[maxfoo]

Since y-splitters for UHF TV aerial leads were selling at £1.50 in a
local cut-price shop, I broke one open to see what's inside.

15kbyte JPEG:
http://anvil.pwp.blueyonder.co.uk/splitter.jpg

Doesn't that have a mismatched half-impedance input? Or am I
misunderstanding something, here?

Can anyone recommend a website that describes RF y-splitters and RF
combiners?

Looks like a LC wilkinson power divider. download rfsim99.exe it lets
you design them.

 

[Dave Farrance]

Looks like a LC wilkinson power divider. download rfsim99.exe it lets
you design them.

It's an interesting program but this circuit breaks its simulator. It
returns an output magnitude of zero.

I think that the transformer model does not handle the fact that
opposing currents applied to matched windings should meet almost no
impedance.