[ICOM] Ct-17 clones... comment

[Dave AA6YQ]

Increasing the drive on the CI-V bus (to handle multiple transceivers) can
be accomplished with a single non-inverting open-collector buffer, like a
7407 section.

http://www.cedmagic.com/tech-info/data/7407.pdf

DigiKey sells these in quantity one for under a dollar.

If you have 12 VDC available, a 7805 3-terminal regulator gets you the 5VDC
needed by the MAX232 and the 7407. It would be hard to cram these three
parts into a DB-9 connector shell, but even in a plastic box they'll be a
lot cheaper than a CT-17. And the result will actually conform to the CI-V
bus spec (which requires an open-collector driver), which the CT-17 fails to
do (the MAX232's TTL output is not open collector).

     73,

        Dave, AA6YQ

-----Original Message-----
From: icom-bounces at mailman.qth.net [mailto:icom-bounces at mailman.qth.net]On
Behalf Of Larry
Sent: Saturday, December 01, 2007 4:15 PM
To: 'ICOM Reflector'
Subject: RE: [ICOM] Ct-17 clones... comment


You are correct Doug, if you are running many things at once you are better
off with the CT-17. The cost for any of the good clones would be more than
one CT-17. 73 OZ

Larry Wassman W3OZ
ARRL #1 Honor Roll
www.w3oz.com


-----Original Message-----
From: icom-bounces at mailman.qth.net [mailto:icom-bounces at mailman.qth.net] On
Behalf Of Doug Faunt N6TQS +1-510-655-8604
Sent: Saturday, December 01, 2007 10:14 AM
To: icom at mailman.qth.net
Cc: icom at mailman.qth.net
Subject: Re: [ICOM] Ct-17 clones... comment

But it's NOT "just like a CT-17"-  I have yet to find a self-powered
interface that will drive more than one radio, and the CT-17 will
handle 4.

And sometimes you want to use RTS and DTR for signaling purposes,
rather than for power.

There are cases where this capability is useful.  I've had two ICOMs
on the table, and switched control among them by changing the software
configuration, or run them from a satellite tracking program that
knows multiple addresses.

A CT-17 is overkill, usually, but not always.  OTOH, you could build a
real clone of a CT-17 for lots less money then ICOM wants for it.
http://www.usersmanualguide.com/icom/accesories__others/ct17

73, doug

   From: "Larry" <w3oz at msn.com>
   Date: Sat, 1 Dec 2007 09:36:44 -0800

   Mel that is true, but Neil will build you one that is self powered just
like
   the CT-17 still for a fraction of the price. I have both running Vista
and
   they are interchangeable. Really. 73 OZ

   Larry Wassman W3OZ
   ARRL #1 Honor Roll
   www.w3oz.com

   -----Original Message-----
   From: icom-bounces at mailman.qth.net [mailto:icom-bounces at mailman.qth.net]
On
   Behalf Of Mel Martin
   Sent: Saturday, December 01, 2007 8:20 AM
   To: icom at mailman.qth.net
   Subject: [ICOM] Ct-17 clones... comment

   "Unless you need a CT-17 specifically there are a lot of after market
   devices that so the same thing at a fraction of the price."

   I think I'll put the record straight here.

   The CT-17 is a true RS232 to TTL converter using a MAX232 chip. It ALWAYS
   works. Many of the "cheap" interfaces do NOT convert to a true RS232
   standard and often work, but sometimes don't. Also the CT17 does not
attempt
   to power it's self from the RTS signal as do most "cheap" interfaces
which
   occasionally creates problems with laptops.  Caveat emptor!

   BTW, yes I do use a "cheap" interface and it's working fine... But I have
   had problems with them in the past, especially with older Icoms. I also
have
   a spare CT-17... But I'm hanging on to it as it is the Gold Standard in
   level converters ;-)
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Icom Users Net: Sundays, 1700Z, 14.316 MHz
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----
Your Moderator: Dick Flanagan K7VC: icom-owner at mailman.qth.net
Icom Users Net: Sundays, 1700Z, 14.316 MHz
Icom FAQ: http://www.qsl.net/icom/