TEK-150

DS1 Retimer / Filter - Model TEK-150

Product Overview

In today's evolving network topologies, edge aggregation element deployments have increased while still employing DS1 network interfaces. These remote switches are connected through various transport and routing elements, rather than through dedicated copper cable. Maintaining accurate timing of edge and remote switches is therefore difficult because the timing traceability and stability can become corrupted or untraceable within these transit elements. Spectracom's Timing Enhancement Kit (TEK™) provides a simple, economical solution to this problem.

Core and host systems accept timing references from a Building Integrated Timing Supply (BITS). Edge devices and remote switches generally do not have external clock inputs, instead deriving their timing from the host via the network DS1 line(s). The remote acts as a slave clock following the input. This makes the stability of this element susceptible to buffer delay variations, TDMoIP variations, wander, and pointer adjustment. These timing deviations can cause the clock in the remote switch to lose sync with the core network or host element, compromising effective data/voice delivery.

The TEK-150 Retimer/Filter reconstitutes the timing accuracy and stability of the network DS1. The device employs a unique line retiming buffer that ensures the DS1 stream is delivered at the accuracy of the local reference. Accurate rate is established and phase transients are removed from the DS1 line at the point of use. If the reference is lost, the TEK-150 reverts to its embedded filtering algorithm, ensuring DS1 line continuity while mitigating detrimental transients.

Installing a TEK-150 is a simple method for reconstituting and maintaining network standard frequency for edge/remote devices that does not require specific transport network topology knowledge or assignment. The TEK is a compact, hard-wired device designed to mount inside the physical cabinet of the remote switch. Unlike external timing units, the TEK has no need for east/west coding, making the input and output designations more intuitive. This design also minimizes the risk of cascading errors caused by improper connections.

For installations external to the remote switch, Spectracom offers a rack kit for mounting in 19 inch EIA racks or 23 inch WeCo racks.

Technical Specifications

PERFORMANCE
Digital PLL Operation	Bandwidth 0.1 Hz (wide) or 0.005 Hz (narrow); switch-selectable
	Phase Buildout Input phase changes of ≥3.5 µsec over an interval of ≤0.1 second are absorbed by DPLL without causing ≥0.05 UI (32 nsec at DS1 rate) phase change on the output. Input phase changes of ≤1.0 µsec over interval of ≤0.1 second are not built-out.
Jitter Filtering	When synced to an ideal (jitter-free) signal, the output jitter is ≤32 nsec (0.05 UI at DS1 rate) peak-to-peak
Wander Transfer	When timed by an input signal whose TDEV is less than or equal to the following levels:
	Integration Time T (seconds) Input TDEV (nanoseconds) 0.05 < T < 10 100 10 < T < 1000 31.6 x T^0.5 1000 < T N/A
	The TDEV of the output signals is less than or equal to the following levels:
	Integration Time T (seconds) Input TDEV (nanoseconds) T < 0.05 N/A 0.05 < T < 0.1 1020 x T 0.1 < T < 10 102 10 < T < 1000 32.2 x T^0.5 1000 < T N/A
Reliability	Estimated MTBF > 400,000 hours
INPUTS / OUTPUTS
Power Input	Dual (A & B) –48 VDC; isolated lugs with protective covering
AMI Input & Output, BITS Input, Alarm Relay Contacts	Tip/ring; 0.045” wire-wrap leads with protective covering; 2A max relay contacts.
Alarm Conditions	Operates with either Super-Frame (SF) or Extended Super-Frame (ESF).
Input Framing	Loss of one or both power inputs Internal failure of unit
Line Coding Selection	AMI or zero-suppression (B8ZS)
Input Selection	BITS input automatically selected if signal is present and valid; if no valid BITS signal available, unit filters AMI input signal
Output Impedance	DS1: 100 ohm +/-6%
Output Level (DS-1)	0 dB (default) or -7.5 dB; switch selectable
Output Squelch	User settable output squelching on fault or loss of timing reference.

Physical & Environmental Specifications

ELECTRICAL
Supply Voltage	-36 to -72 VDC, ± 2 VDC
Supply Current	Steady-state: 100 mA (at 48 VDC) Start-up: 250 mA (at 48 VDC)
Start-up Voltage Transients	0 V to 75 V
ENVIRONMENTAL
Operating Range	23° F to 158° F (-5° C to 70° C)
Rate of Change	+/-86° F/hour (+/-30° C/hour)
Storage Range	-40° F to 185° F (-40° C to 85° C)
Relative Humidity	5-95%, non-condensing
Vibration	0.008 g^2/Hz @ 5-20 Hz; 0.05 g^2/Hz @ 20-100 Hz
PHYSICAL
Size/Weight	6.8125” W x 1.875” H x 4.0” D, 1.0 lbs (173.0 mm W x 48.0 mm H x 102.0 mm D, 0.45 kg)

Ordering Information

TEK-150	DS1 Retimer / Filter
Mounting	19" EIA / 23" WeCo Rack Mounting Kit