Adtran H4TU-R Card (1246026L4) Normal Status Lights

Light	Status	Description & Suggested Action (Likely Failures in Bold)
DSL1/DSL2	Unlit	No sync. // Call your Carrier.
	Red	Poor signal quality. // Call your Carrier.
	Yellow	Marginal signal quality. // Call your Carrier.
	RED - Flashing	Error detected on HTU-C or HTU-R. // Call your Carrier.
DS1	Unlit	Premise equipment T1 signal not present or wrong format. // Call your Vendor.
	RED - Flashing	Premise equipment T1 signal errors. // Call your Vendor.
ALM	Red	Local alarm at HTU-R Card detected.
	Yellow	Remote alarm at HTU-C Card detected.
ESF/SF	Unlit	Unframed mode. // Call your Carrier.
	Yellow	ESF Framing
	Green	SF Framing
B8ZS/AMI	Yellow	B8ZS
	Green	AMI
LBK	Yellow	Active local loop back at the HTU-R.

For more information or to have your device listed please contact Infotel Systems

The Story Behind "Status Lights"

Infotel Systems . 6008 Hermitage Rd . Richmond, Virginia 23228

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