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| ===== Description ===== | ===== Description ===== | ||
| - | The Power-Mite 3A is the same as the [[pm3|Power-Mite 3} with the addition of break-in keying with adjustable delay. The Power-Mite 3A has four circuit boards with VFO transmit and receive on 40 and 20 meters and sidetone. | + | The Power-Mite 3A is the same as the [[pm3|Power-Mite 3]] with the addition of break-in keying with adjustable delay. The Power-Mite 3A has four circuit boards with VFO transmit and receive on 40 and 20 meters and sidetone. |
| The receiver is comprised of a variable oscillator operating on the received frequency, a mixer and high gain audio amplifier. The received signal is converted directly to audio where a filter eliminates undesirable signals, and then amplified to headphone level by a high gain audio amplifier. The variable oscillator covers 7.0 to 7.3 MHz for 40 meter operation and is doubled to 14.0 to 14.6 MHz to cover 20 meters. | The receiver is comprised of a variable oscillator operating on the received frequency, a mixer and high gain audio amplifier. The received signal is converted directly to audio where a filter eliminates undesirable signals, and then amplified to headphone level by a high gain audio amplifier. The variable oscillator covers 7.0 to 7.3 MHz for 40 meter operation and is doubled to 14.0 to 14.6 MHz to cover 20 meters. | ||
| The transmitter, driven from the same oscillator-multiplier used for receiving, has an isolation stage, driver and push-pull final amplifier. It is keyed in the buffer stage. The output circuit is a Pi network to match 50-75 ohm unbalanced loads. A side-tone oscillator with variable frequency and volume is keyed along with the buffer stage. | The transmitter, driven from the same oscillator-multiplier used for receiving, has an isolation stage, driver and push-pull final amplifier. It is keyed in the buffer stage. The output circuit is a Pi network to match 50-75 ohm unbalanced loads. A side-tone oscillator with variable frequency and volume is keyed along with the buffer stage. | ||
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| ===== Related Links ===== | ===== Related Links ===== | ||
