The speakers used in the BM-17 are very sensitive and don’t require much AF gain from the transceiver. The frequency response is 200 Hz – 5 kHz with very low distortion. The ear pads are replaceable acoustic foam.
The BM-17-IC headset, using our IC electret element, was created for use with Icom radios. This element has been made to utilize bias power in ICOM radios which addresses low-gain issues that arise when using dynamic elements. This element must be paired with the AD-1-IC (included) or AD-1-ICM adapter. The IC adapters have no internal DC blocking capacitor so bias voltage can be passed allowing the IC electret element to operate. The IC element has an operating frequency response of 35 Hz – 12 kHz.
The microphone audio for the BM-17 series terminates into a 1/8” mono plug while the headphone terminates into a 1/8“ stereo plug (1/8” to 1/4” adapter included).
Note: To use dynamic mic elements on vintage radios (requiring a high impedance input of 10k to 30k Ohms) will require the use of an XT-1 impedance matching transformer.
The use of the AD-1 series mic adapters allows simple interface with popular transceiver inputs. The adapter cable has a 1/8” female input jack for the headset microphone while the 1/4” female that exits the adapter is the PTT (push to talk) line for the Heil foot switch or hand switch. The 1/8” or 1/4” stereo plug goes into the headphone jack on the transceiver front panel.