Unverified85% confidenceCautionTime unknown
仅覆盖13.56MHz高频段，无法屏蔽125kHz低频门禁卡或UHF超高频信号，如有多频段防护需求不适合
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85%
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UnverifiedIEEE 1789标准规定：频率＜90Hz时频闪深度需＜3%为豁免级，90-1250Hz需低于频率×0.08%，达此标准即视为无频闪危害74% similarUnverified购买时应认准明确标注屏蔽频段（13.56MHz和125kHz）及衰减值（如≥60dB）的产品，只笼统写'RFID Blocking'而无频段和参数的属于营销话术，验证成本高74% similarUnverified接入现有报警主机时必须确认信号频率与协议匹配：国内无线常见433MHz，部分品牌用315MHz或2.4GHz，跨频率无法联动；有线联动要看主机输出是12V电平还是继电器触点73% similarUnverified选购HF电台必须配套自动天线调谐器（ATU），因HF频段跨度大（2-30MHz），无调谐器时天线仅能在窄频段谐振，实际可用频道大幅受限73% similarUnverified不适合需要隔离低频振动（如主机低转速工况）的场景，邵氏硬度50-60度的NBR卷材固有频率偏高，对低频段减振效果有限73% similar
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