Signals G_STOP, +_STOP disappear only with the return of the amplifier in the RX mode. Amplifiers U1:2, U1:3 for SWR-POWER meter.
Protection - comparator U1:4. Keys switching - VT3, VT4, VT5, VT6. Relays RX-TX; ANT A - ANT B - K1. VT1, VT2 control the operation of the relays.
U1:1, VD10, VD12 form a voltage of negative polarity to ALC protect the transceiver. VD6, R37 - ALC voltage to the transceiver.The voltage of the negative polarity. VD1, RU1 - protection of static voltage from the antenna. The size of the core TR1 10x20x15mm allows you to measure the power of at least 2000W.
At the same time resistance of loading has to be 50 Ohms. To manage protections of amplifier OUT Unit gives several options signals. Open drain up to 100mA, U. +_STOP - output +12V up to 100mA. If SWR exceeds value (which you will choose as resistors R21, R29) - VT3 will open.
VT3 will stay open through VT4, while there is a voltage of +12V_TX. When switching to RX mode - protect turns off.A-B - switching the antenna A - antenna B. To switch to apply a voltage of +5-12V. +12V_TX - Voltage +12V TX from the amplifier, which switches the amplifier from RX-mode to TX mode. The graph shows the dependence of the output voltage on the transmitted power.
The item "TANDEM MATCH 2kW SWR POWER meter protection RX-TX ANT A-B LDMOS MOSFET BLF188XR" is in sale since Friday, July 14, 2017. This item is in the category "Consumer Electronics\Radio Communication\Parts & Accessories\Meters". The seller is "dnradio" and is located in Europa. This item can be shipped worldwide.