Specifications
On
the
QTB-3
there
is
a 34-pin header denoted
by
J3. A standard
5.25
inch floppy disk
cable
will
plug into
this
board in
this
area
and
connect
directly
to
the
edge
connectors of
your
floppy disk drives. This
same
34-pin header
is
used
for connecting 8 inch drives. This
can
be
done
by
taking a regular
50
pin ribbon cable
and
replacing the 50-pin female header with
a
34-pin
female header.
Strip
away
lines
48
through
50
and 1 through 13
to
give
you
the
required
34
position cable. Either set of cable
can
be
purchased
from
Megatel.
To
allow a
mixed
5.25
and
8 inch system Megatel
can
supply a cable
which
provides both a
34-pin
and
a 50-pin connector.
Assembl
ing
your
own
mixed
drive cable, although possible,
is
difficult
due
to the difference between 8
and
5.25
inch
drive interfaces.
The
next
step,
for
a mixed
drive
system,
is
to
wire wrap from
the
floppy
disk
data
transfer
rate
(pin 8-17
on
the 96-pin
DIN
connector)
to
the drive
select
line
(see appendix
for
pinout)
you
have
chosen
for
your
8 inch drive. This allows the data
transfer
rate
to
switch
automatically with drive
selection.
Notes
regarding
Floppy
Disk
Drives:
Megatel
Quarks
do
not
provide a
MOTOR
ON
signal.
Most
5.25
inch drives
wi
II
provide a
jumper
option
on
the drive
motor
control board to
have
the
motor
come
on
with the
selection
of
the drive. Please consult
your
drive
manual
to insure
this
is
done
before
you
try
to
boot up
the system.
Some
5.25 inch
drives
have a
READY
signaL.
If
you
are
using such a
drive,
you
must
isolate
the
READY
line in a
mixed
drive
installation.
If
you
are using
an
8
and
5.25
inch
drive system the
READY
line should
be
taken
directly
from
the
QTB-3
to
the 8 inch drive, while
bypassing the
5.25
inch
drive.
MegateL
Quarks
do
not provide a
HEAD
LOAD
signal for 8 inch drives.
Most
8 inch drives
wiLL
have
a
HEAD
LOAD
with drive
select
jumper option
on
the drive
motor
control board. Please
consult
your
drive
manual
to ensure
this
is done.
Recommended
Monitors for the Megatel
QUARK
Many
direct-drive
and
composite monitors
can
be
used
successfuLly with the
QUARK.
The
user should beware,
however,
that
some
of the cheaper composite monitors
on
the market could
operate poorly.
The
most
common
difficulty
with
such
monitors
is
their
inability
to
display a
full
80 characters. This
is
because they do not
meet
the
tight
timing requirements of the
Quark
composite signal's horizontal retrace time.
These
monitors
can
sti
II
be
used
if
the
number
of characters per
row
is
reduced through software modifi cations.(only
on
SBC's
with
graph
i cs opt ions)
Before purchasing
any
monitor
check
with the
vendor
to
see
if
you
wi
II
be allowed
an
evaluation period. This
is
the best
way
to
avoid possible disappointment.
The
following is a
list
of
recommended
monitors
that
display a
full
80 characters per
row:
Manufacturer
Zenith*
Electrohome
ELectrohome
Model#
ZVM-121
EVM
1220
EVM
1519
Input
Type
Composite
Composite
Composite
Manufacturer
Electrohome
Electrohome
Model#
EVM
1719
EVM
2319
Input
Type
Composite
Composite
*Note
-
The
Zenith
ZVM-121
is
a widely excepted monitor
which
works
well with the Megatel
QUARK.
The
Zenith
ZVM-121
is
avai lable
at
most
retai
l chains
and
sells
for approximately
$100.00.
Megatel
Computer
Technologies Toronto,
Canada
Page
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