Jump to content

SG7500A SWR Scans - 2.jpg


Lscott

I picked up a Diamond SG7500A dual band antenna to use on my new vehicle. It's a 1/2 wave design so it shouldn't need a ground plane.

https://www.diamondantenna.net/sg7500a.html

It's going to be installed on the roof rack. Since there isn't going to be much if any ground plane I wanted to see how much of a difference it would make. I did two sets of tests, no ground plane, and with a set of ground radials bent at a 45 degree angle. The addition of the ground radials made a very noticeable difference in the SWR scans. The no ground plane scans look OK but seems to be biased a bit towards the higher frequencies. That can be adjusted with a small change in length of the bottom element. There are set screws there for this purpose, however the manufacture claims it's "factory" tuned.

I was hoping the bandwidth might be high enough to cover the Ham bands along with MURS / GMRS. Ah, maybe with some tweaking if the vehicle installation approximates the ground radial test setup enough.


From the album:

Misc. Radio Gear

· 38 images
  • 38 images
  • 1 comment
  • 22 image comments

Photo Information


Recommended Comments

There are no comments to display.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Add a comment...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and Guidelines.