VHF Aerial repair

[gregrae]

I have a Unien MC535 VHF Marine Radio
Transmitt Frquency Range 156 to 158 MHz
Receiver Frequency Range 156 to 163 MHz
The aerial on the Boat is 2.350 Meters from tip to base. The winding from the tip down is 533 mm in length befor the wire goes into the whip aerial.down to the Coil at the base of the aerial.I kept the coil as shown in the attachement.
I replaced the insulation wirer from the coil to the tip rewinding the wirer all the way to the tip.
as the existing wirer insulation was breaking off. Do I have to SWR in the aerial.
The Coax has to be replaced but I do not know what length to make the coax as there is a joiner in the section of the wirer.that has corroded away and I want to remove the joiner.(I have baught a length of coax..Can I replace the Coax with a shorter length.
Where do I solder the screan wirer and the Ceter wire of the coax to the coil as the 8.2 uf ceramic cap is solded to the center taping of the coil.as shown on my sketch.
I will place pictures to help you out

 

[Evert]

You can use any length of coaxial cable as long as your radio is at least 3 feet away from the antenna.

Yes you do have to check the SWR.

The center conductor of the cable goes to the free end of the wire leading to the capacitor.

The cable shield (“screan wirer”) goes to the wire leading to the bottom of the base coil.

I wonder if your upper section has the right number of turns and spacing?

 

[Fast1eddie]

Ditch it and buy a new one.

 

[gregrae]

Yes I can ditch the aerial but that is not the way to learn about the aerial and it design.I am retired and I live from week to week I enjoy learning about different things.
Thank you for your suggestion if I could I would.
Greg

 

[gregrae]

How do I work out the wrigt number of turns and spacing.
Can you tell me the formula for working out the VHF wave length.When I work this out Is the mesurement the length of the aerial from tip to base dos this have any thing to do with the wire
What is th coil at the base of the aerial for
Thank for your reply
Greg

 

[n8emr]

If your goal is to learn about antenna then continue playing with it. If your goal is to have a working antenna, trash what you have and buy a new one.