problem in antenna switch circuit

Hi, everyone, I am doing a transceiver system working in 25MHz carrier.
A single electrode was used to be both transmitting antenna and receiving antenna. Apparently, a antenna switch was needed.
The transmit signal was acquired by series LC resonance circuit. As a result, it had a high voltage (approximately more than 50V) and low current.

Initially, I used analog switch IC (ADG749) to implement the antenna switch. Because of the high voltage, it was impossible to let the transmit signal go through ADG749. A solution as in the attached picture was test. In the solution, the transmitter will be shut down when the system worded as a receiver. It works well. However, when the system worded as a transmitter, the transmit signal voltage shrank too much because of the voltage clamp effect of the input pin of ADG749. It cannot be accepted.

I do not know how to resolve this problem. Please help me improve it or suggest a new one. Thanks in advance.

Best Regards.

Hector

I good way to resolve such problems is to carefully read the data sheet. You are putting 50 V into a switch that is, at best, rated to 5.5 V. I am surprised it did not melt on your PC board.

I doubt you are going to find a semiconductor IC to handle that much RF swing. You will have to make one out of discrete parts, either fets or pin diodes.

That means the parasitic capacitance at S2 port is too high when the switch is in TX mode. Try to do a simple impedance matching adding a series inductor with S2 port. To find the right inductor value have to measure first the impedance at S2 (in TX mode) using a VNA.