When winding a coil, in order to smoothly un-coil the Litz wire from the paper spool, the simple method is: Vertically fix a 1/4-inch diameter screw rod on a flat plate, and then put paper spool into screw rod flat. When you pull out the litz wire from the paper spool, the paper spool can rotate freely on the screw rod, and the litz wire will not be twisted and knotted. Here you are bidding on a NOS vintage Chinese Military headphone and microphone set. These communications headset microphone were manufactured around 1970, design for the Chinese Military semiconductor transceiver. This EH-5 headset microphone is a collectable item and will be a welcome addition to your collection. Perfect for ham transceiver, very good for coping cw signals. Its microphone has two 580Ω magnetism elements i.
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