CHAPTER 2 (CONT.)
WHATIS FAST TYPE?
Fast Type is a modified code from 45B standard. It can speed up to 110B for a fast typist. If Fast
Type mode is turned on, the unit will automatically recognize the speed and change from 45baud
to 110 baud. Fast Type will not benefit well for the thumb-type keyboard of the PocketComm, but
it will be good for receiving. However, this mode will request a small handshaking procedure
before sending, and pause for checking interrupt requests that are sent from the receiving unit. For
an average or slow typist, this mode causes more delay time in transmitting or receiving than
standard Baudot. If the other typing is slow, you may need to turn fast type off. That is the reason
the PocketComm was designed to have Fast Type in receiving mode only.
HOWTO CHANGE YOUR POCKETCOMM TO USE FAST TYPE
Press (CTRL)+(F) to toggle from normal to Fast Type mode. The display will read: ‘[FASTTYPE
ON]’. Press space bar to initialize the unit. If the display reads: ’[NORMAL]’press space bar
again to initialize it. Then press (CTRL)+(F) to change code. To check the current code setting
press (CTRL)+(S).
[FAST TYPE ON] [VCO OFF]
[MOBILE] [MIX] [45B]
CELLULAR PHONE USERS WITH FASTTYPE:
The Cellular phones use high frequencies to carry the coded voice signal over the air. This signal
is combined in a package and mixed with other signals in a same channel before sending. The
package sometimes is delayed and can cause the PocketComm to reject the package or may
decode the package wrong. This problem will be fixed if you use the PocketComm with a TTY
compatible cellular phone. Those phones will open a priority channel to send the coded TTY
signal package to the receiver with no time delay to protect the error rate. However, sometimes
natural sources such as lightning, tornados, or mountains take effect on the link and cause a loss
of the signal. The signal can fade out or cause dropped calls.
When the message is garbled (caused by bad receiving) first try to improve the signal on the
cellular phone. Move the phone to the window or an open area and watch the signal icon on the
display until you get a full bar graph. Other generators in your house could also interfere with the
receiving such as microwaves, radios, televisions etc. Move away from these sources and try your
call again.
Fast Type transmitting units will require a response from the receiver after it sends out the first
handshake character before it changes to Fast Type speed. The waiting time is very short. The new
digital TTYcompatible cellular phones will need a small time to study the incoming signal before
it changes to TTYcompatible mode and send out a string of characters. This delay is longer than
the TTYwaiting time and will cause the transmitting device to turn off Fast Type mode before the
receiving unit is able to responded to the first hand-shaking character. Our suggestion is turn off
Fast Type before making a PocketComm-cellular phone call. It will speed up both transmit and
receiving tremendously.
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