A used Nokia baseband unit should be bench tested as a system, not just powered on. For a Flexi FSMF or an AirScale set (AMIA subrack, ASIA or ASIB common unit, ABIA capacity card), the test comes down to six checks: the labels match your order, the hardware is undamaged, the unit starts cleanly on a stable -48 V DC supply, it is recognised in Nokia’s management tool with no active hardware alarms, the software on the unit can be brought to your network release, and the radio and transport ports bring up stable links. A short burn-in then catches heat-related faults. This checklist explains each step so faulty cards are found on the bench, not during a site visit.
Why baseband needs its own test plan
Radio units are tested mainly for output power and VSWR. Baseband is different: the risk lies in control, transport and fronthaul functions, and in the combination of cards. An AirScale capacity card can look fine on its own and still fail to come up because the common unit, subrack slot, software release or SFP type does not match. A used FSMF may still carry the previous operator’s configuration and software, which affects how it behaves on your bench. A structured test plan covers these points before the unit is shipped to site.
Units covered and what to confirm
The table lists the Nokia baseband units most often traded on the used market, with the product codes printed on their labels.
| Unit | Product code | Platform | Role | Key test focus |
|---|---|---|---|---|
| FSMF | 472181A | Flexi Multiradio 10 | System module (control, transport, baseband) | Fans, LEDs, LMP access, RF/EXT optical ports, EIF1/EIF2 transport |
| AMIA | 473098A | AirScale | Indoor subrack, 2 common and 6 capacity slots | Backplane connectors, fans, DC input |
| ASIA | 473095A | AirScale | Common unit (control and transport) | LMP access, backhaul ports, sync, recognition of capacity cards |
| ASIB | 473764A | AirScale | Common unit (later generation) | Same as ASIA; required common unit for ABIO |
| ABIA | 473096A | AirScale | Capacity card | Detection in the subrack, 6 optical RF ports (OBSAI or CPRI up to 9.8 Gbps) |
If you are still choosing which cards to buy, our guide to buying used Nokia AirScale baseband covers valid card combinations.
Step-by-step bench test
1. Label and identity check
Compare the product code, version suffix and serial number on each label with the purchase order. Do not rely on a front-panel photo or the short name in an offer: AirScale common units and capacity cards come in several variants, and an ASIA ordered for an ABIO site, for example, is the wrong part. Record every serial number on receipt so it can be matched to the inventory reported by the management tool later.
2. Visual and mechanical inspection
- FSMF: check the IP65 casing, front covers and seals, the DC input connector, the RJ45 ports (LMP and EIF1), the HDMI sync connectors and every SFP cage. The FSMF fan assembly is connected to the core module by a cable, so make sure the fans are fitted and the cable is intact.
- AirScale cards: inspect the backplane connectors for bent or pushed-in pins, and check SFP cages, ejector handles and front panels.
- AMIA subrack: check the backplane, fans, DC input and blanking plates for empty slots, which keep the airflow correct.
A card with damaged backplane pins should not be inserted, because it can damage the subrack.
3. Power-up and LED check
Use a stable -48 V DC bench supply with enough current. Nokia specifies the FSMF at -48 V DC nominal (-40.5 V to -57 V range), with 125 W typical and 180 W maximum consumption for the core module; extension sub-modules add to this. For an AirScale set, power the subrack with at least one common unit and one capacity card, since that is the minimum working configuration.
Watch the LEDs during start-up. On the Flexi system module, the status LED is briefly red during self-test or reset, which is normal. If it stays red or blinks red, the module is reporting a major or critical alarm; yellow means standby or blocked. The fan LED should be green. Use Nokia’s LED tables for the exact unit and release to interpret anything else.
4. Management access and hardware alarms
Connect a laptop to the LMP (local management) Ethernet port. Flexi system modules such as the FSMF are managed with BTS Site Manager; AirScale is managed through Web Element Manager (WebEM) in a browser. Once connected, confirm that:
- Every unit is detected with the correct product name and serial number. On AirScale, the common unit should list each capacity card in its slot.
- No hardware or unit faults are active. Note any alarm that remains after start-up and check whether it follows the card when you move it to another slot.
- Temperature readings and fan status look normal.
5. Software and configuration
Used units usually arrive with the software and configuration of the previous network. Check the installed release and decide whether to upgrade before testing further. On Flexi, an “incompatible SW version” alarm is typical until the software matches the site; the alarm clears once the correct release is loaded. On AirScale, Nokia provides the BTS Rescue Console for installing software on the common unit when needed. Nokia documentation also describes a reset button under the EIF1 port of the FSMF that clears configuration data when held for about five seconds, followed by a manual reset; use it only when you intend to remove the old configuration.
Remember that licences are managed by the network, not by the hardware. Capacity and features you see on the bench depend on the licences and configuration you load.
6. Fronthaul and transport links
A unit that boots is not proven until its ports carry traffic. Insert SFPs of the type the site uses and connect at least one radio, or a loop arrangement supported by your test setup, to each optical RF port you intend to use.
- FSMF: test the RF/EXT optical ports (OBSAI or CPRI at up to 6 Gbps) and both transport interfaces, EIF1 (electrical Gigabit Ethernet) and EIF2 (optical).
- ABIA: test the six optical RF ports. They support OBSAI RP3-01 or CPRI up to 9.8 Gbps, so use the protocol and rate of the radios that will be connected.
- ASIA: test the backhaul ports you plan to use (3 x 1G electrical and 2 x 10G optical Ethernet) and the sync input if the site uses external timing.
Links should come up without errors and stay stable. Intermittent link alarms usually point to a dirty connector, the wrong SFP type or a damaged port.
7. Cell setup and burn-in
Where possible, commission a simple test configuration with a radio connected into dummy loads and set up a test cell, so the baseband actually processes traffic. Then leave the system running for several hours. ABIA cards are specified for an operating temperature of -5°C to 55°C, so run the burn-in in a normal environment with the subrack fans working. At the end, recheck alarms, temperatures and link status.
Test record template
| Check | Tool | Pass condition |
|---|---|---|
| Label and serial | Visual, purchase order | Code, variant and serial match the order |
| Mechanical | Visual | No damage to pins, cages, connectors, casing or fans |
| Power-up | -48 V DC supply, LEDs | Clean start, no persistent fault LED |
| Detection | BTS Site Manager or WebEM | All units listed with correct name and serial |
| Alarms | BTS Site Manager or WebEM | No active hardware alarms |
| Software | BTS Site Manager, WebEM or Rescue Console | Release matches the target network |
| Links | SFPs, radio, management tool | RF and transport links stable |
| Burn-in | Test cell, several hours | No new alarms, normal temperatures |
Common faults found on used baseband
- Bent backplane pins on AirScale cards after careless removal.
- FSMF fans missing or not working, which leads to temperature alarms during burn-in.
- Damaged SFP cages or optical ports that cause intermittent link alarms.
- Wrong card combinations, such as an ABIO with an ASIA common unit.
- Old software or configuration that blocks commissioning until it is upgraded or cleared.
Radio units need a different test focused on transmit power and VSWR; see our Nokia RF module testing checklist.
FAQ
Can I test an ABIA card without a common unit?
No. An AirScale capacity card needs a subrack and a common unit such as the ASIA or ASIB to be detected and managed. The minimum working set is one common unit and one capacity card.
Which software do I use to check a Nokia FSMF?
Flexi system modules are managed locally with BTS Site Manager through the LMP port. AirScale system modules are managed with WebEM in a web browser.
Is a red status LED at start-up a fault?
Not on its own. On Flexi system modules the LED is red for a few seconds during self-test or reset. A red or blinking red LED that stays on after start-up indicates an alarm that needs checking.
Do I need a radio connected to test baseband?
Basic checks do not need one, but fronthaul links and cell processing can only be verified with a radio or a suitable test setup connected through matching SFPs.
Source tested Nokia baseband
We supply used and refurbished Nokia Flexi FSMF system modules and AirScale baseband, including the AMIA subrack, ASIA common unit and ABIA capacity card. See the full range in our Nokia category. 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. Contact us on WhatsApp at +86 187 3329 4669 or +86 139 3088 8705, email jack@telecombts.com, or use the form on our contact page with the product codes and quantities you need.
We also buy surplus Huawei, Ericsson and Nokia equipment. See sell your equipment.