About this replacement
Viavi JDSU Acterna ANT-5 — 7.2V Ni-MH Replacement Battery (B04021228)
This is a 7.2V, 3500mAh Ni-MH replacement battery for the JDSU Acterna ANT-5 antenna analyzer and related JDSU SDH test instruments. It replaces OEM part B04021228 and restores field operation to portable network testing and survey equipment. Voltage and capacity match the original pack specification exactly.
- ANT-5 and JDSU SDH platform fit: These instruments share the same battery bay dimensions, 7.2V rail, and connector pinout. The BMS handshake on each model reads cell voltage and temperature via the same NTC line, so one pack serves the full group without modification.
- Bench tested on actual hardware: We cycled this pack through charge and discharge on the ANT-5 platform and monitored BMS response at initialisation. The pack passed cell balancing checks and held voltage within spec under sustained measurement load.
- Post-install calibration before field deployment: After fitting a new pack, run a full calibration cycle through the ANT-5 instrument menu before heading out. The instrument maps battery state during that sequence — skipping it causes premature low-battery warnings on the first measurement session in the field.
ANT-5 shutting down mid-measurement despite showing adequate charge
The ANT-5 draws a short current spike each time it powers an RF module or switches measurement mode. An aged Ni-MH cell has elevated internal resistance, and that spike causes a brief voltage sag the instrument interprets as a critically low pack. The protection circuit cuts power before the display can update. A fresh pack with low internal resistance absorbs the spike without sagging below the cutoff threshold — typically 6.0V on this platform.
Pack will not charge after the ANT-5 sat unused for several months
Ni-MH cells self-discharge over storage and can drop below the charger's minimum detection voltage — roughly 4.5V for a 6-cell pack. The ANT-5 charger circuit sees a voltage too low to identify as a valid pack and refuses to start a charge cycle. To recover, apply a slow trickle from a bench supply at 0.1C for 15–20 minutes until pack voltage climbs above 5.5V, then place it back in the instrument and resume normal charging.