VHF antenna question

[Joel H.]

So, I think I know what the answer to this is but, not being a radio-head, I want to check before I step my mast.
I rewired my mast including new antenna cable. I assembled and soldered the cable, being vary careful with the soldering technique and checking to make sure I ended up with no continuity between the core and shield wires, as was stressed in the readings. I was happy that things went vary well and everything tested fine.
Then I screwed the connector to the mast top antenna wrapped the connection with self amalgamating tape and went on my merry way.

Today, while putsing around (and in view of the approaching time to re-step the mast), I decided to put the continuity meter on the connector again at the mast base.
Well, sure enough there is now continuity between the inner wire and outer shield. Now, not knowing the internal structure of an antenna, I don't know if this is right. And, I don't want to cut the tape and break the antenna connection if I don't have to!
Thanks in advance for any replies,
Joel H.

 

[Don S/V ILLusion]

Most VHF antennas will do that. Not to worry but to make sure while the mast is still down, remove the antenna and double-check.

 

[Jackdaw]

I'm guessing you should expect 50 Ohms of impedance with the antenna connected...

 

[Don S/V ILLusion]

The impedance of the antenna will not show on an ohmmeter reading continuity of the antenna loading coil

 

[Jackdaw]

The impedance of the antenna will not show on an ohmmeter reading continuity of the antenna loading coil

Good call.. the continuity is being measured with DC. Ah.

 

[rpell1@msn.com]

Sometimes the silliest thing will screw you up. So, please forgive me for asking this question, but.............Before you checked for continuity, did you disconnect BOTH sides of the co-ax cable? And, make sure the connectors were nowhere near anything?

I told you it was silly......

So, I think I know what the answer to this is but, not being a radio-head, I want to check before I step my mast.
I rewired my mast including new antenna cable. I assembled and soldered the cable, being vary careful with the soldering technique and checking to make sure I ended up with no continuity between the core and shield wires, as was stressed in the readings. I was happy that things went vary well and everything tested fine.
Then I screwed the connector to the mast top antenna wrapped the connection with self amalgamating tape and went on my merry way.

Today, while putsing around (and in view of the approaching time to re-step the mast), I decided to put the continuity meter on the connector again at the mast base.
Well, sure enough there is now continuity between the inner wire and outer shield. Now, not knowing the internal structure of an antenna, I don't know if this is right. And, I don't want to cut the tape and break the antenna connection if I don't have to!
Thanks in advance for any replies,
Joel H.

 

[Joel H.]

Thanks for all the replies guys.
Through this and other readings, I've found that the situation I described is normal just as long as the cable shows no continuity between core and shield before you attach the radio or antenna. So I'm good to go.:dance:
Hope everyone has a good summer, with all the improvements I've been able to make this winter, (due to the mild weather!), I know I will.
Happy sailing,
Joel H.