SMS-301 Modem Switch

The SMS-301 is a fully programmable 1:1 protection switch providing complete redundancy for one prime and one backup modem. The SMS-301 switch is designed to operate with Comtech EFData satellite modems and is a direct replacement for the SMS-651B 70/140 MHz switch.

Programming the SMS-301 is accomplished through the front panel keyboard or the remote interface. Complete functionality control and monitoring of switch status and faults are easily accessed through the remote port connection.

The SMS-301 simultaneously switches data and IF paths, either independently or dependently. The switching type is selectable through the front panel or remote port, eliminating the need for firmware changes and allowing maximum in-use flexibility.

When a fault is detected in the online modulator or demodulator, a switch to the offline modem occurs if the backup is not in a faulted condition. The transmit data is sent to the backup modem by the 1:1 switch to prevent false indications of transmit faults. The actual switching can be accomplished in under 20 milliseconds, with programmable modulator and demodulator switching delays in the range of 0 to 127 seconds.

The front panel LEDs indicate which modulator and demodulator (prime or backup) are online. The LEDs also indicate the following:

• Active faults in the modulator or demodulator
• Status of the SMS-301?s redundant power supplies
• Mode of the switch (automatic or manual)

FEATURES

• Full feature monitor and control processor
• Remote input for configuration and status
• 1:1 configuration
• 1 rack unit (RU) chassis

OTHER FEATURES

• Uses standard Comtech EFData modem as backup or prime
• Dependent or independent modulator and demodulator switching
• Local/remote, automatic/manual control
• Redundant power supplies and AC inputs
• Easy installation

MAP PRICES

There are places on our web site and in our print ads, where the spaces for prices are intentionally left blank. In other instances, the advertised; price is higher than the price you actually pay when you order that item. The reason for this is MAP, or Minimum Advertised Price.

MAP is a voluntarily agreement a retailer enters into with a supplier. According to the agreement, which varies in details from vendor to vendor, the retailer can sell an item for any price they wish, but may not advertise the item for an amount less than the Minimum Advertised Price. These agreements help level the playing field for both the small retailer and the giant retail chain. Retailers agree to MAP contracts because the vendor makes it worthwhile for them to do so. A retailer who abides by the agreement can count on getting first news and early shipments of new products, and generally enjoys a "favored" status.

At Satcom Resources, while we abide by our MAP agreements, we want to make it as easy as possible for you, our customer. Where there is a lower selling price and we can, we will volunteer it -- no need for a nod-and-a-wink or a secret password. At Satcom Resources, our lowest selling price is always what you pay. Some Online Retailers make it difficult to tell you about lower-than-MAP prices. At Satcom Resources, we've set up workarounds. Either we ask you to call, or we will e-mail the price.If you still have any questions about MAP policies, feel free to contact us via e-mail at info@satcomresources.com.