{"product_id":"standard-horizon-hx270s-replacement-battery-72v-1800mah-ni-mh","title":"Standard Horizon HX270S FNB-V57 Replacement Battery 7.2V 1800mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eStandard Horizon HX270S \/ HX370S \/ HX600S — 7.2V Ni-MH Replacement Battery (FNB-V57)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 7.2V, 1800mAh Ni-MH replacement battery for the Standard Horizon HX270S, HX370S, HX500S, and HX600S handheld marine VHF radios. It replaces OEM part numbers FNB-V57, FNB-V57H, FNB-64, FNB-64H, FNB-83, and FNB-83H. It fits the original battery compartment and connects via the same contact arrangement as the factory pack.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eHX270S \/ HX370S \/ HX500S \/ HX600S compatibility:\u003c\/strong\u003e\n    These four models share the same 7.2V two-cell Ni-MH pack format, connector pitch, and BMS handshake threshold. One battery covers all four radios on this platform.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this pack through charge and transmit cycles on the HX270S dock. The BMS accepted charge on first insertion without fault. Voltage held steady under simulated PTT draw without tripping overcurrent cutoff.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eMarine VHF contact maintenance:\u003c\/strong\u003e\n    Salt air accelerates corrosion on the battery contact strip. Before first use, wipe the gold contacts on both the battery and dock with a dry cloth. A corroded contact can prevent the dock from reading the pack correctly and trigger a fault state before charging begins.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the HX270S drops to reduced TX power mid-call on a fresh Ni-MH pack\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eNi-MH cells at storage voltage sit around 1.2V per cell at rest but sag under the transmit current spike — which on a 5W VHF radio can exceed 1.5A. If the pack hasn't completed a full charge cycle, cell voltage under load can dip below the radio's low-voltage TX threshold, triggering an automatic power reduction. This isn't a fault with the battery. Run a complete charge cycle before the first transmit session and the sag narrows significantly.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBar indicator showing one fewer bar than expected after inserting new pack\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe HX270S uses a voltage-threshold bar indicator, not a capacity-measuring circuit. A new Ni-MH pack ships at storage voltage — typically 7.0–7.2V — not at full charge. At that voltage, the radio displays one fewer bar than a fully charged pack at 8.4V. This is not a fault. Charge the pack fully in the OEM dock or a compatible Ni-MH charger and the bar indicator will read correctly.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43426352103514,"sku":"BWCS-FNB67TW-1","price":38.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43426352136282,"sku":"BWCS-FNB67TW-2","price":44.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43426352169050,"sku":"BWCS-FNB67TW-3","price":49.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-FNB67TW-1.webp?v=1779930807","url":"https:\/\/batteryweb.com\/products\/standard-horizon-hx270s-replacement-battery-72v-1800mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}