Rack Mount or Chassis Modems

The rack mount chassis measures 19 inches wide by 5.25 (3U) inches high, and fits into standard EIA cabinets. The chassis holds 16 single-channel modems, as well as two power supplies. The modems slide into the chassis and connect to a 16-channel back plane. The multiple power supply configuration allows for a redundant configuration. Any of the three possible modems (Bell 202, Bell 202T or V.23 ) manufactured by Applied Systems Engineering can be inserted into the rack chassis.

Power Supply

The 16 Channel Modem Chassis contains slots for two standard 3U x 9HP VME power supplies (Figure 3-5). The power supply is a 40-watt universal input (90 to 254VAC) with over voltage protection and continuous short circuit protection. The power supply has a single output +5VDC at 8.0 Amps and does not require a minimum load to obtain regulation. The power supply module contains a +5VDC adjustment pot that is accessible from the front panel and can be adjusted +/- 0.3 volts.

Power Supply

The 16 Channel modem chassis does not require both power supplies to operate, and can run on a single supply. The second power supply can be added to provide the user with a higher mean time between failure. The power supplies are also hot swappable.

Back Plane

The back plane for the Rack modem is used to terminate the RS232 and TELCO connections. The picture below shows the back plane in detail.

Rack mount Modem:

The main difference from a rack modem to the stand alone modem is the terminations. The rack modem has a connector which is inserted into a back plane, where as the stand alone modem has all of the required connectors to interface to external equipment ( DB25 RS232 connector, TELCO RJ11 jack, etc.).

Rack mount Specifications:

ITEM	CHARACTERISTIC
DATA RATES	0-1200 bps
OPERATING MODE	Half or full duplex; 2 or 4-wire private line
OPERATING FORMAT	Asynchronous, binary, serial
LINE REQUIREMENTS	Voice grade, private lines
LINE IMPEDENCE	600 ohms, balanced
BELL 202 MODULATION	Bell Frequency Shift Keying (FSK) Mark, 1200 Hz; Space 2200 Hz ; Soft Carrier, 900 Hz
V.23 MODULATION	V.23 Frequency Shift Keying (FSK) Mark, 1300; Space 2100 Hz; Soft-Carrier, 900 Hz
BELL CARRIER FREQUENCY	1200 Hz and 2200 Hz ± 1%
V.23 CARRIER FREQUENCY	1300 Hz and 2100 Hz ± 1%
TRANSMITTER	Output Level: 0 dBm, switch selectable to –31 dBm in 1 dBm increments RTS/CTS Delay: 0 to 254 mS, switch selectable (8 mS) 900 Hz Soft Carrier On Time: 0 to 15 mS (2 mS)
RECEIVER	Receiver Operating Range : 0 to –35 or –45 dBm Receiver Squelch: 0, or 156 mS for 2-wire Carrier Detect On Delay: 2 to 30 mS (8 mS) Hysteresis: 2 dB minimum
ELECTRICAL ISOLATION	Power Supply: 1800 Vac Telco Connection: 1500 Vrms (Primary to Secondary)
ENVIRONMENTAL	Operating Temperature: 0 - 70 ° C Storage Temperature: -40 to 80 ° C Humidity: 0 to 95% Relative Humidity (non-condensing)
PHYSICAL CHARACTERISTICS	Rack mount: 19 in. rack is 5 ¼ in. high with slots for 16 modems, plus redundant power supplies
POWER	5 VDC @ 100mA per card
USER EQUIPMENT INTERFACE	25 pin EIA Connector (RS232C Compatible)
TELCO INTERFACE	Terminal Blocks
DIAGNOSTIC	Analog Loopback Switch
FRONT PANEL LED DISPLAY	TXD, RXD, RTS, CTS, and CD

You may contact us in Campbell, CA by phone at 408-364-0500, fax to 408-364-0550, or via email at products@ase-systems.com.

Normal business hours are 9:00AM to 6:00PM Pacific Time, M - F.

Applied Systems Engineering, Inc.
1671 Dell Avenue, Suite 200
Campbell, California 95008
Phone: (408) 364-0500 • Fax: (408) 364-0550
Email: products@ase-systems.com

If you would like additional information on any of the ASE products or would like to discuss your specific requirements with a sales engineer, you can call directly or fax/e-mail the information about your requirement and a sales engineer will contact you.