Feeding a Antenna without shield of cable

Hi.

This is a basic question, when feeding a waveguide with a coaxial cable, using the inner cable pin to feed the waveguide (without a conector, its feeding directly), but the shield of the cable does not touch the waveguide, will the antenna still work or does affect a lot?

Also, is there any danger to the RF equipment radio when doing this?

Thanks

Providing the dimensions of the coax are small the RF travelling down it will be voltage and current and will have the ration of the Z0 of the cable. Once the screen is removed the RF then sees the wide world and will radiate, depending on the length of the bare inner and the frequency the ratio of the voltage to current will not be Zo but could be anything.
In a wave guide there are fields that propagate down it so a suitable "launcher" is required to match the Zo of the coax cable to the wave guide.
Doing what you intend could end up that most of your RF is radiated from the unscreened cable, with not much getting into the waveguide at all. At the amplifier end the reflection from the radiating part of the cable could cause excessive VSWR and destroy the power amplifier.
Frank