The following circuit is based on a commercial design from the 1970s covering 0.8 - 500Mhz in six switched ranges. The sensitivity is slightly reduced on the highest range because the diodes are effectively in series - this can be solved by adding an extra switch wafer to select the appropriate diode output on each range.

Resistor R1 ensures that the sensitivity cannot be reduced to zero and is typically about 2 - 5% of the value of R2 so set R1 = 220R and R2 = 10K.

The sensitivity and selectivity can be improved a little by the use of a unity gain op-amp buffer to drive the meter and reduce the loading on the tuned circuits although this is more effective on the lower frequency bands where the LC ratio progressively increases. In this case set R1 = 22K and R2 = 1Meg. Protect the Op-amp input using diodes to the positive and negative rails.