Micronta field strength/SWR tester. Used, not tested. It was in use by my late Father in his Radio Shack (G8DHQ). Micronta Field Strength SWR Tester Cat. No. 21-525B;Measurable RF Power: 1 to 1000 watts,SWR: 1:1 to 3:1,Impedance: 50 ohms,Frequency: 3 to 30 MHz
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