Receiver Front End Overload

[kato56]

Can someone tell me how much signal a front end can withstand before damage occurs ?

If a receiver (analog or digital) hears a .1 microvolt signal which converts to approximately -126 dBm (@ 50ohms non-amplified by a pre-amp, unity gain antenna etc.), and let's say a 20 watt transmitter is near by ~ 20 feet on a unity gain antenna (approximately +43 dBm) on the same frequency, could the +43 dBm carrier damage the receiver after a period of time, or is there a spec that I'm not seeing on receivers that will reveal this ?

Thanks

[Jim202]

Can someone tell me how much signal a front end can withstand before damage occurs ?

If a receiver (analog or digital) hears a .1 microvolt signal which converts to approximately -126 dBm (@ 50ohms non-amplified by a pre-amp, unity gain antenna etc.), and let's say a 20 watt transmitter is near by ~ 20 feet on a unity gain antenna (approximately +43 dBm) on the same frequency, could the +43 dBm carrier damage the receiver after a period of time, or is there a spec that I'm not seeing on receivers that will reveal this ?

Thanks

There is always a chance that the transmitter can cause some damage. You didn't say just what the radio receiver was. Some receivers are very prone to failure from front end overload. Others are built like a battle ship and can take a considerable beating.

You can make a simple mod to the front end by adding a couple of hot carrier diodes back to back from ground to the input of the first solid state device. Just make sure your not grounding the bias it needs to operate and that you have a series resistor to limit the current through the diodes.

Jim

[kato56]

Thanks for the response... The receiver is part of an XPR-8300 Mototrbo repeater.