{"product_id":"anritsu-ms2721a-replacement-battery-111v-7800mah-li-ion","title":"Anritsu MS2721A Replacement Battery 11.1V 7800mAh Li-ion","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAnritsu MS2721A \/ MS272xB Series — 11.1V Li-ion Replacement Battery (1420-0868)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 11.1V 7800mAh Li-ion battery replaces OEM part 1420-0868 in Anritsu MS2721A and MS272xB series handheld spectrum analyzers. It fits the MS2721B and MS2723B alongside the wider MS272x platform. Use it to maintain continuous field operation during RF measurement, signal analysis, and frequency monitoring work away from AC power.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eMS272x platform compatibility:\u003c\/strong\u003e\n    The MS2721A, MS2721B, MS2723B, and related MS272x variants share the same 11.1V battery bay, connector pinout, and BMS handshake protocol — which is why a single cell covers the full series without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through full charge-discharge cycles on the MS272x platform and confirmed the BMS handshake completes correctly, the charge IC accepts the cell, and the status indicators respond accurately across the charge curve.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePower-on self-test sequence:\u003c\/strong\u003e\n    After fitting this battery, let the analyzer complete its full startup self-test without interruption. The MS272x runs a BMS verification pass at boot — cutting power during this sequence registers a false battery fault that persists until the next clean reboot.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the MS272x BMS rejects a new cell on the first charge attempt\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe MS272x series uses a charge IC that applies a conservative current limit when it cannot read a valid charge history from the cell's BMS register. On a new battery, that register is blank — so the IC may throttle charge rate or briefly stall before accepting the cell as valid. This is not a fault with the battery or the analyzer. One complete charge cycle from near-empty to full clears the register and the charge IC behaves normally from the second cycle onward.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCharge indicator stuck below 100% after first full charge\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eNew cells arrive with the BMS capacity register unlearned, so the MS272x charge controller applies a conservative upper limit on the first charge — the indicator may plateau at 95–98% and not advance. This is a calibration artifact, not a defective cell. Discharge the analyzer normally until the low-battery warning triggers, then charge uninterrupted to completion. After this first full cycle the charge IC recalibrates and the indicator reaches 100V consistently. Target a termination voltage of 12.6V to confirm the cycle completed fully.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43381504639066,"sku":"BWCS-AMS272MD-1","price":281.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43381504671834,"sku":"BWCS-AMS272MD-2","price":335.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43381504704602,"sku":"BWCS-AMS272MD-3","price":376.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-AMS272MD-1.webp?v=1778901324","url":"https:\/\/batteryweb.com\/products\/anritsu-ms2721a-replacement-battery-111v-7800mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}