RE: Maximum distance for SCART

[Keith Doxey]

The KAT5 Transmitter uses less than 120mA and the Receiver about 60mA so
the
distance is greater than that.

At work I have some CCTV cameras running over CAT5 using a mini KAT5 PCB.
The camera power is also derived from the same supply (about 200mA) and
there is only about 0.5V drop on the whole cable run which is about 40
metres (possibly longer).

Dont forget to doible the resistance as that is for a single wire and you
have the same on the return.

The first KAT5 prototype (Composite, Stereo and IR) was tested at well over
600m but that is with local power supplies.

Keith

-----Original Message-----
From: Andrew Richards [mailto:<a
href="/group/kat5-users/post?postID=1FNg96qibAbGYo5omr3tem5f2LALoOrKR21E5SbglhpMIOex17X89v6ywkIYyIM1wAF0Vt4uutbh5ogBdKIP-lzQRebdivKXaA">andrew.richards@p...</a>]
Sent: 11 December 2001 18:12
To: <a
href="/group/kat5-users/post?postID=YxZzNvjBbwXGsQI3h3Pc0Y7RIOnqVlg7dwc57MtJJJE5i5cXUKYOdDpYIkJE6fRPe9M5oAVbXQ_zLPpUIxSiNoM">kat5-users@xxxxxxx</a>
Subject: RE: [KAT5] Maximum distance for SCART


Nick

CAT5 (per core) is generally quoted at around 100 ohm/km, which equates to
a
100mV drop per metre per amp.

In another post, Keith said his KAT5 units will work at 9v, and I believe
they consume 300mA. If my maths is right this suggests a theoretical
distance of 100m before you've dropped more than 3v. Personally, I'd use
all 4 pairs.

Best regards

Andrew




-----Original Message-----
From: Nick Towers [mailto:<a
href="/group/kat5-users/post?postID=M4g4rvPG4Ya71TSFZ7VQ8h9Y0Bjt7jbzIHwVK_5G3WnX2Sq5YLyWHG-PcDcmaqPwQI7iSL7zR5Y">nickt@t...</a>]
Sent: 11 December 2001 15:17
To: <a
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Subject: RE: [KAT5] Maximum distance for SCART


Hi Keith,

I like the idea of this remote power scheme - much neater than wall warts.
Can you let me know though what are the considerations using Cat5 for
power - eg what is resistance per metre and is resistance of per
plug/socket
connection significant? any inductance/capacitance considerations? Max
current? Max impedance/ internal resistance of source power supply? Do you
use a twisted or split pair or double up pairs so more current can be
handled? Question does not just relate to KAT5, but an indication of what
KAT5 could cope with in terms of max length of CAT5 etc would be useful.
Thanks

Nick