What Coax connectors are these?

[claycookiemonster]

I'm ready to go to Coax School, so I went through all my boxes and antennas to see which connectors I need (rookie here) but these have me stumped. On the rear of a Garmin GNC 355 are the connections for Comm and GPS, but what are they? No threads. No bayonets. Just a clean conical place.

 

[Jetmart]

Does it slide into a rack that has bayonets?

 

[mburch]

The radio has to be able to slide in and out of the rack without disconnecting anything... there will be a feature on the radio rack that this mates with, and which presents a standard BNC fitting for you to connect your antenna cable.

 

[pazmanyflyer]

I'm ready to go to Coax School, so I went through all my boxes and antennas to see which connectors I need (rookie here) but these have me stumped. On the rear of a Garmin GNC 355 are the connections for Comm and GPS, but what are they? No threads. No bayonets. Just a clean conical place.

Isn't there a back plate that is wired and attached to the back of the tray. The 355 slides into the tray and then connects to the back plate. The coax cables are attached to the rear of the back plate.

 

[rv6n6r]

Isn't there a back plate that is wired and attached to the back of the tray. The 355 slides into the tray and then connects to the back plate. The coax cables are attached to the rear of the back plate.

Right, these are standard for antenna in/outputs. Note the flared end so as to correct any misalignment when the radio goes in. Mating connector will be something like:
https://www.steinair.com/product/bnc-tray-straight-mount/

 

[RV7A Flyer]

Section 4.4.3 of the Installation Manual has a diagram which shows the connector that this goes into.

The backplate will look something like this:

 

[BillL]

To the OP there are BNC and TNC connectors for Garmin. The B is the bayonet and the T is threaded. T is a much lower loss connector. Both can connect to RG400 coax. A shop like Stein or Aerotronics will help train you with your purchase. They both are very helpful during the build and well into Phase II.

https://www.steinair.com/product-category/connectors/antenna-connectors/

 

[claycookiemonster]

Of course!

Sparkling reactions, guys. Of course! I was only looking at the box, and not the nice tray Stein sent me. Ask a stupid question, and get a wise answer. Thanks again.