150-504-100-03
Appendix A - Technical Reference
HRE-504 List 1, List 1B, and List 2
August 1, 2002
31
The physical location of the HRE-504 doubler enclosures is driven by one of three deployment rules:
1
The first and most important rule is to place each enclosure span to the electrical limits of 35 dB. This places
the first doubler at the 35 dB location, the second at 70 dB, and the third at 105 dB. These electrical settings
allow the maximum range of 140 dB if the fourth span to the remote unit is also 35 dB.
2
If the first rule is not applicable, then make all the spans the same electrical length (same 196 kHz loss). This
minimizes span loss and maximizes operating margin, resulting in the optimum transmission performances.
If specific application constraints preclude using Rule 2, or two different circuit layout choices have the same
maximum span loss, then use Rule 3.
3
If the first two rules are not applicable, use rule 3. To minimize the power consumption and dissipation of the
line unit that powers the doubler or remote units, Span 1 must be a minimum and Span 3 must be a maximum.
This choice minimizes the I
2
R loss in the cable pairs and reduces the thermal stress on the line unit.
Only the HDU-409, EDU-409, and HDU-407 doublers can be used in circuits with more than three
spans.
Summary of Contents for 150-2202-01
Page 4: ...Inspecting the Shipment 150 504 100 03 iv August 1 2002 HRE 504 List 1 List 1B and List 2...
Page 8: ...List of Tables 150 504 100 03 viii Augusr 1 2002 HRE 504 List 1 List 1B and List 2...
Page 53: ...Appendix D Abbreviations 150 504 100 03 46 August 1 2002 HRE 504 List 1 List 1B and List 2...
