Please help a new ham tune his radio

[Turbo T]

So of curiosity, on a dual band antenna, when i want to talk 70 cm from 2 m, do I need to remove one of the two whips along with the loading coil?

 

[ab4d]

My SWR's are like 2.5 and they get worse the higher you go in frequency.

I tried raising the antenna but no dice. The antenna consists of two metal whips with a load coil in the middle.

Anyways I'm a bit stumped. What should I do? I want to get on the air and start talking.

Thanks in advance.

As someone already stated, you need to LOWER the antenna. If you SWR reading gets higher as you go up in frequency, the antenna is too long.

 

[ab4d]

So of curiosity, on a dual band antenna, when i want to talk 70 cm from 2 m, do I need to remove one of the two whips along with the loading coil?

No, the antenna should be fine. Dual band antennas are designed to run both bands as they come.

 

[Turbo T]

No, the antenna should be fine. Dual band antennas are designed to run both bands as they come.

Thanks, if I may ask, how does this work? I understand a lower frequency requires a longer antenna and vice versa. I was under the impression that to use this on 440 from 144, I'd need to remove one of the two whips. (the Tram 1180 dual bander I have is 2 whips with a center loading coil in the middle)

 

[Beetle]

The entire length of the antenna is a center-loaded whip on 2 meters; the coil effectively stops the RF at 70 cm, so only the bottom portion is radiating.

The antenna automatically "disconnects" the upper portion at that higher frequency.

 

[Captain Kilowatt]

The entire length of the antenna is a center-loaded whip on 2 meters; the coil effectively stops the RF at 70 cm, so only the bottom portion is radiating.

The antenna automatically "disconnects" the upper portion at that higher frequency.

Not all antenna work that way Pat. Some dual band antennas are phased such that on 2m it acts as a 5/8 wave while on 70cm it may act as a 5/8 wave over a 5/8 wave over a 1/4 wave or some other such configuration. The entire length of the antenna is active on both bands.For instance the Diamond SG-7900A functions as a pair of 1/4 waves over a 3/8 wave on 2m and as three 5/8 waves in phase on 70cm. BTW, it works REAL good too but I had to go with something a bit shorter and went to the Comet CA-2X4SR.

Diamond® Antenna ~ SG7900A Dualband Mobile Antenna

 

[Beetle]

I stand corrected; not familiar at all with the Tram. I was describing my old Larsen dual bander. Still haven't put an antenna on the Subaru.