About this replacement
Applied Instruments Super Buddy 21/29 — 7.2V Ni-MH Replacement Battery (742-00014)
This 7.2V, 3000mAh Ni-MH battery replaces the original pack in the Applied Instruments Super Buddy, Super Buddy 21, and Super Buddy 29 portable satellite signal meters. It matches the OEM voltage rail, connector, and cell count required by the meter's power circuit. Capacity is 3000mAh (21.6Wh) — taken from product data, not estimated.
- Super Buddy series fit: The Super Buddy, Super Buddy 21, and Super Buddy 29 share the same battery bay geometry, connector pinout, and 7.2V supply requirement. All three models accept this pack without modification to the bay or charging circuit.
- Bench tested on actual hardware: We ran this pack through the Super Buddy's charge cycle and confirmed the BMS accepted the cells without fault codes. Load testing under simulated signal-scanning draw showed stable voltage with no mid-session cutoff events.
- First-deployment cycle for satellite meters: After installing, run a full calibration cycle through the Super Buddy's instrument menu before heading to a job site. The meter maps battery state during that sequence, and skipping it causes the low-battery indicator to trip early on the first measurement session — before the pack is actually depleted.
BMS lockout after the Super Buddy sat unused in a carry case for months
Ni-MH cells self-discharge even when idle. If the Super Buddy spent an extended period in storage, the pack voltage can drop below the BMS recovery threshold — typically under 6V for a 7.2V six-cell pack. At that point, the charger may show no activity or the meter may refuse to power on at all. A slow pre-charge at low current (often called trickle or recovery mode on compatible chargers) can bring the cells back above the recovery floor before full charging resumes. If the pack does not respond after 20–30 minutes at trickle, replace it — deeply discharged Ni-MH cells that sat for months often have one or more reversed cells that will not recover.
Super Buddy shutting down mid-scan when the display and RF section load simultaneously
During active signal scanning, the Super Buddy drives the display backlight, RF front end, and processing simultaneously. This combined draw creates brief voltage sag on an aged or partially discharged pack. If the sag drops the supply rail below the meter's undervoltage lockout threshold — around 6.0V under load — the device shuts off even though the battery indicator showed capacity remaining. This is a load-response issue, not a calibration fault. Swap in the fresh pack, run the calibration cycle from the menu, and confirm the meter sustains voltage above 6.4V under scan load before returning the unit to the field.