How can I improve the video quality of analog FPV?

It depends. What quad are you using? Is it a bnf? Some things you can do:

1. Upgrade goggle antennas (stock are... fine, but you could do better).

2. If available, turn up output power.

3. Try changing channels. Race1 (lower frequencies) usually has better range/penetration, but Race8 is high enough to be out of the range of wifi devices. Also, considering the tuning of antennas certain channels might perform better. Play around with it.

4. Maybe better camera? Is there a capacitor? I think that helps. Does your vtx have a 5v output? If so, running the camera off of that might give a cleaner signal.

At the end of the day, those goggles won't be groundbreaking, but you can improve them a bit.

I am using a mob 8, so the only camera that'll fit is a CADDX Ant

I have been looking at analog goggles (Cobra X V4) but they are almost more expensive than avatar goggles L so I cannot justify the cost when I could just go digital.

A couple things that have helped me are,

keep the connections cleaned every couple months. The dust and dirt does make a difference.

the Omni antenna should be tall enough to clear the top of your head. It’ll give better reception behind you.

a cheap yet surprisingly good camera is the Runcam phoenix. JB edition just has deeper color. Both are great.

keep the wires to the cam and vtx as short as you can this helps with RF noise, and twist them.

a used mechanical pencil eraser will polish your fpv camera lens.

check and reset your camera lens focus for time to time as vibration/crashes over time will unfocus it.

last two

the connectors do wear out over time and will give worse performance.

if your good with a soldering iron, you can direct solder antennas and get better performance from them. But I wouldn’t mess with that unless your confident in that area.

I know that’s lot haha, I hope some of that helps you.