omsi@reed.UUCP (OMSI) (01/13/84)
Recently received my Anchor Automation Signalman Mark XII modem and
am quite pleased with it. Up till now, I've been using a US Robotics
Password (for about a month), so I'll mention a few differences and
problems.
The most obvious difference is that the USR has a speaker, while
the AA does not. The AA has 4 indicators on the front for power,
carrier detect, data, and high/slow speed (1200/300 baud). Also the
AA can detect dial tone and busy signals. The AA prints "CONNECT" at
300 baud, and "CONNECT 1200" at 1200 baud carrier detect. This is nice
when you're typing at 1200 baud, and you get a 300 baud carrier, you know
it and can switch over. The AA also has 2 RJ11 jacks so that the phone
can be connected to the AA without a 1 to 2 adaptor. The AA is physically
larger than the USR, but the phone rests comfortably atop the AA, while
the USR shape is bizarre. The USR has double sticky tape on the bottom
so it can be mounted in a convenient place like the side of a desk, etc.
The USR has 4 accessible DIP switches in the back for RS232 pin 8 and 20
control, manual ring, and balance. The USR also has internal switches
for reversing pins 2 and 3 (transmit and receive data). The AA manual
mentions none of these options, and I have yet to open the box. (Doing
so is not easy). Of course both are Hayes protocol compatible, and
run off DC adaptors. I have heard the AA will run off 2 9-volt batteries,
but there is no mention of this in the manual, so I have my doubts.
The USR power switch is in the rear (minor nuisance), the AA in the
front.
As far as problems go, I've noticed the USR occasionaly turns the
transmitter tone on on autodial for no apparent reason. Also it only
accepts commands in upper case. This sometimes takes me a while to catch.
The AA doesn't seem to have these problems. With the AA, to abort an
autodial, you must type 'a', whereas with USR and Hayes, any char will
do. Oddly, the AA cannot send BREAKs. Not too sure why not, unless
it was an oversight. I never need BREAK, but I can imagine this could
be a real problem for some users. As I recall, BREAK is often useful
in getting certain machines (MICOM?) to switch baud rate. Not to
mention machines that prefer BREAK to ^C. I imagine this is just a
software problem because I understand the AA (like the USR) is mostly
digital, and the USR handles BREAK properly.
As you can see I have few complaints with the AA. This may be
because I've had more experience with the USR. In either case my
complaints are minor, and for general operation they both work quite
well.
Bob Ankeney
tektronix!reed!omsi