• (1) Stackable MiniHub
• (1) External 120-VAC, 60-Hz
power supply
• (1) Velcro tape section,
approximately 3 inches
(7.6 cm) in length
• (2) Brackets for optional
wall-mounting
• (1) User’s manual
• (1) Stacking cable
Standards — All: 10BASE-T;
LE2801A: 10BASE5;
LE2801A-BNC: 10BASE2;
LE2801-FO: 10BASE-FL
Data Rate — 10 Mbps
Diagnostics — Via LEDs or network
software
Indicators — (18) Front-mounted
recessed LEDs:
(1) Power; (8) Link/TX
(1 for each port);
(8) Pol/RX (1 for each port)
Leads/Signals Supported — Pins 1,
2, 3, and 6
Partitioning — Automatic after 32
consecutive collisions
Reconnection — Occurs after 512
bits of error-free transmission
Maximum Segment Length —
UTP: 328 ft. (100 m);
STP: 492 ft. (150 m);
AUI drop cable: 164 ft. (50 m);
BNC: 607 ft. (185 m);
10BASE5: 1640 ft. (500 m);
10BASE-FL multi-mode
fiberoptic: 6562 ft. (2 km)
Connectors — All: (8) shielded
RJ-45, (1) DB15 female,
(2) stacking bus headers;
LE2801A-BNC: (1) BNC;
LE2801A-FO: (2) Fiber ST
User Controls — Rear-mounted
slide switch for straightthrough versus crossover
(uplink) operation on port 8;
Stackable switch to specify
which hub is at the base of
the stack
Enclosure — High-strength steel
Cooling Method — Convection
MTBF — 50,000 hours
Temperature Tolerance —
Operating: 32 to 122°F (0 to 50°C);
Storage: -4 to +140°F (-20 to
+60°C);
Humidity: 10 to 95%,
noncondensing
Power — From wallmount power
supply: Input: 95–125 VAC, 60 Hz;
Output: 12 VDC, 1 amp;
Consumption: 10 watts maximum
Size — 1"H x 6.8"W x 4"D
(2.5 x 17.2 x 10.1 cm)
Weight — 1.3 lb. (0.6 kg);
With power supply: 2.3 lb. (1 kg)
The Complete Package
Operating Features
Specifications
Ordering Information
ITEM CODE
Stackable MiniHub ....................................................LE2801A
Stackable MiniHub-BNC ...............................LE2801A-BNC
Stackable MiniHub-Fiber ..................................LE2801A-FO
Stackable MiniHubs perform
signal amplification, retiming of
data packets, and regeneration of
preamble bits for each packet
received. They also detect
collisions, extend collision
fragments, and automatically
partition and reconnect individual
ports. This section describes a
few of these features in greater
detail.
Preamble Regeneration
As per Ethernet standards,
the MiniHubs add bits to the
preambles of output packets so
that each output packet contains
a minimum 64-bit preamble.
Collision Condition
When carrier is detected
simultaneously on multiple ports,
a jam pattern is generated on
each port to create a collision
condition. When a collision signal
from one port is detected, it
generates a jam pattern to other
ports.
Partitioning and Reconnection
Stackable MiniHubs will
automatically partition any port
where 32 consecutive collisions
occur or after 6.5 ms of
continuous transmissions.
Network integrity is checked
every 800 ms, and the segment is
reconnected after one 512-bit
packet is transmitted without an
error.
Fragment Extension
The Stackable MiniHubs will
automatically add bits to a
received data packet of less than
96 bits (a ”fragment”) so that the
size of the packet sent on toward
its destination is at least 96 bits.