Basic Dipole Reactance question

[Retroradio]

I always build mine looking for a decent SWR, 50ohm impedance and a 0X reactance. I have never seen like the readings delineated below.

My buddy sent me a screenshot of his rig expert on his 20m dipole and its:
SWR 1.81
R 40.7ohm
X -25.4ohms. (That’s a negative)

Simple explanation is the antenna is not efficient or properly built. Got it.

So the antenna geek in me has a question…I cant find an answer online as to what is the effect of -ve versus +ve Reactance.
Efficiency, reflected power and a SWR influence but are the effects the same be it negative or positive?

An aside…His tuner recently died and he’s thinking this caused it.

 

[FreqNout]

https://palomar-engineers.com/non-resonant-vs-resonant-antennas

This link may help answer your question.

 

[Retroradio]

https://palomar-engineers.com/non-resonant-vs-resonant-antennas

This link may help answer your question.

Thanks!

 

[jwt873]

My buddy sent me a screenshot of his rig expert on his 20m dipole and its:
SWR 1.81
R 40.7ohm
X -25.4ohms. (That’s a negative)

As in the link FreqNout supplied, you can see that an antenna can have pure DC resistance as well as capacitive reactance and inductive reactance.

X is either capacitive or inductive reactance. If it shows positive, it's inductive.. A negative value means that it is capacitive reactance. So your buddy's antenna has 25.4 Ohms of capacitive reactance. It's most likely too short (as in the purple schematic in the palomar link).