When you buy a used Ericsson baseband unit, the model name on the quote is only the starting point. Before you order, confirm the exact product number and R-state on the label, understand that capacity and features depend on your own licences rather than the hardware, check the physical condition of the ports and power connector, and make sure the unit has been functionally tested. This guide walks through each check for the Baseband 6630, 6631, 6648 and the RAN Processor 6651, so a spare or expansion unit works in your network the first time.
1. Start With the Exact Model and Product Number
Ericsson baseband units are identified by a product number in the KDU format, printed on the product label together with a revision (R-state) and a serial number. Two units sold under the same commercial name can carry different product number suffixes, so always match the full number to what is already installed or approved in your network.
The table below shows the product numbers most commonly seen on labels of the units we handle, and what a buyer should confirm for each.
| Model | Product number commonly seen on label | What to confirm before ordering |
|---|---|---|
| Baseband 6630 | KDU 137 848/11 | Same product number and suffix as your installed units; software release in use on your network |
| Baseband 6631 | KDU 137 0071/11 | Full product number and R-state; whether your planning approves it as a like-for-like spare |
| Baseband 6648 | KDU 137 0015/11 (other suffixes such as /12 also exist) | Which suffix your network uses; LTE and/or NR role at the target site |
| RAN Processor 6651 | Check the label photo | Full product number and R-state; the role it will take in your RAN design |
If you are still deciding between generations, our earlier article Ericsson Baseband 6630 vs 6648 explains how the two platforms differ. This guide focuses on what to check once you know which model you need.
2. Ask for Clear Label Photos
A clear photo of the product label is the single most useful thing a supplier can send. From one photo you can confirm:
- Product number – the full KDU number including the suffix after the slash.
- R-state – Ericsson’s hardware revision marking (for example R1A, R2C). Different R-states of the same product number are usually interchangeable, but some operators specify a minimum revision, so check your own requirements.
- Serial number – needed for your asset register and for any warranty claim.
- Label condition – a damaged, missing or replaced label makes identification and traceability difficult.
For larger orders, ask for label photos of every unit or a full list of serial numbers, not just one sample photo.
3. Understand Licensing Before You Buy
This is the point that most often surprises first-time buyers. On Ericsson RAN nodes, capacity and optional features are controlled by software licences that are managed per node under the operator’s licensing arrangement with Ericsson. The hardware itself does not carry a usable licence to a new owner.
In practice this means:
- Do not plan capacity on the assumption that a used baseband “comes with” licences from its previous network.
- Check with your Ericsson licensing contact or your own planning team how a replacement or additional baseband will be licensed in your network before the unit arrives.
- For like-for-like replacement of a failed unit, follow your normal hardware replacement procedure for licence handling.
A reputable supplier will sell the hardware and say so clearly; be cautious of any offer that promises transferable licences.
4. Check the Software and Configuration State
Units removed from live networks may still hold the configuration and software of the previous operator. That is normal for decommissioned equipment, but your integration team needs to know what to expect:
- Ask whether the unit has been reset or still carries a previous configuration.
- Confirm which software release your network requires and plan the upgrade or downgrade as part of integration.
- Plan commissioning time for loading your own configuration, transport settings and licence handling.
5. Inspect the Physical Condition
Baseband units are rack-mounted and usually live indoors or in cabinets, so they tend to age better than outdoor radios. Even so, inspect these points on photos or on arrival:
| Area | What to look for |
|---|---|
| Radio interface (RI) and transport (TN) ports | Undamaged SFP cages, no bent springs, no debris; dust caps fitted if possible |
| Power connector | Intact DC terminals, no burn marks or corrosion |
| Grounding point | Thread and contact surface in good condition |
| Housing and front panel | No dents that affect rack fit, no missing screws, intact LED windows |
| Airflow path | Clean intake and exhaust; no blocked vents or heavy dust build-up |
Also confirm what is included. SFP modules, mounting brackets and cables are often not part of the unit itself. Your radios and transport network need the correct optics, so specify whether you need them supplied.
6. Confirm Compatibility With Your Radios and Transport
A baseband only works as part of a complete site. Before buying, check that:
- The radio units on site (for example Ericsson Radio 2219, 4415 or 4428 families) are supported in the configuration you plan to run.
- Your required software release supports both the baseband model and the radios.
- The transport interface and optics match your backhaul.
- Power and rack space at the site suit the unit.
A newer baseband is not automatically a drop-in replacement for an older one. For a failed unit, the same product number is usually the fastest route back to service; a move to a newer generation is a planning decision, not just a hardware swap.
7. Ask How the Unit Was Tested
“Tested” can mean very different things. Ask the supplier what their test covers. A useful functional test for a baseband should at least confirm that the unit powers up and boots normally, the status LEDs and alarms show no hardware faults, and the interfaces are recognised. Ask for test records or photos where possible, and confirm the warranty period in writing.
Quick Pre-Order Checklist
- Exact model and full product number, including suffix
- R-state and serial number of every unit (label photos)
- Licensing plan agreed with your own team
- Required software release and configuration plan
- Physical condition of ports, power connector and housing
- Accessories needed: SFPs, brackets, cables
- Test scope and warranty terms
FAQ
Do licences transfer with a used Ericsson baseband?
You should not assume so. Capacity and feature licences are managed per node under the operator’s arrangement with Ericsson. Plan licensing with your own team before the unit is installed.
Can I replace a Baseband 6630 with a Baseband 6648?
Not automatically. It depends on your radios, software release, transport and licences. For simple maintenance, the same product number as the failed unit is usually the most practical choice.
Does the R-state matter?
Units with the same product number and different R-states are generally interchangeable, but some operators set a minimum revision. Check your own hardware requirements and ask for the R-state on the label photo.
What should I send when asking for a quote?
The model, full product number, quantity, required software release if known, and whether you need SFP modules or other accessories.
Source Tested Ericsson Baseband Units
TelecomBTS supplies used and refurbished Ericsson equipment, including the Baseband 6630, 6631, 6648 and RAN Processor 6651. Every unit is functionally tested before shipment, and radio units such as RRUs are also VSWR tested. All equipment comes with a 90-day warranty, and we ship worldwide in secure packaging. Send us the model, product number and quantity on WhatsApp +86 187 3329 4669 / +86 139 3088 8705, email jack@telecombts.com, or use the form on our contact page.
We also buy surplus Huawei, Ericsson and Nokia equipment – see sell your equipment.