HUGE FAVOR - Could someone read resistance on A99 for me???

[UFO411]

If someone has SUPER EASY access to a known working A99, would you mind taking a resistance reading with a volt meter between the center pin and shield on the PL-239 for me? I’m getting 2 ohms there. But, if I read from the shield or center pin to the tip of the A99’s center wire I’m getting nothing or OL.

Does this seem normal to anyone here? I figured I would see something from center pin to tip but to my surprise, the only thing I’m reading is from center pin to shield at 2 ohms. Is my antenna broken???

Thanks!!

 

[freecell]

a99 schematic:

 

[UFO411]

a99 schematic:
View attachment 47192

Clarification, dumb question here but is the coil a choke in the coax or is it internal to the antenna?

 

[freecell]

a99 "ANTENNA" schematic, feedline not included.

 

[freecell]

the center pin @ the SO-239 connector is shorted through the smaller of the two inductors of the matching auto transformer and back to the shell of the connector.

there is no continuity between the connector center pin and the far end of the vertical element due to the rf coupling capacitors (dc blocking) at the base of the 1/2 wave element.

 

[UFO411]

the center pin @ the SO-239 connector is shorted through the smaller of the two inductors of the matching auto transformer and back to the shell of the connector.

there is no continuity between the connector center pin and the far end of the vertical element due to the rf coupling capacitors (dc blocking) at the base of the 1/2 wave element.

That makes sense. I’m struggling here because I haven’t had much experience with RF except with my mobile and even that is minimal.

 

[freecell]

i understand, good luck.

 

[UFO411]

So, after all the testing and troubleshooting, the ONLY thing I can find is evidence of water getting between the threaded connections at the top of the bottom section and the top of the middle section. Nothing in the coax. Nothing on the bottom of the antenna.

That said, I think I will fill all threaded connections and coax connections with DE grease and place marine grade shrink tubing over all of them. I’m hoping this will resolve the problem once and for all.

I’m also going to get an I MAX 2000 on hand in case this happens again.

Thoughts? Ideas?


Thanks!

 

[BJ radionut]

Microsoft Word - The Antron 99 EXPOSED.doc (radiomanual.info)

The Imax 2000 Exposed | CB Radio Magazine

 

[M0GVZ]

Thoughts? Ideas?


Thanks!

DC multimeters are of little to no use for testing antennas due to the fact AC/RF doesn't work like DC and what may appear to be a dead short to DC isn't to AC/RF.