• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Notice: You may not use this site to facilitate the unauthorized selling of copyrighted material including, but not limited to, in the public dxForums, dxGallery, dxChat and private messsages. If you get caught doing this, you will be permanently banned with no second chances. A notice will be placed on the site of why you were banned and any information collected by this site about you will be made known to the copyright holder.

Hi Gain SPT500 Super Penetrator


Well-Known Member
Jan 29, 2006

The SPT-500 should be adjusted to an OAL of 267" as a starting point for 11 meters and then fine tuned from there by adjusting length and beta match and/or grounding wire.

For the strongest vertical, if you overlap the joints by 4", the top radiator will have a 4 1\2" overlap and your OAL will be 267". Exposed lengths would be:

M1 = 71"
M2 = 48"
M3 = 51"
M4 = 49.5"
Top = 47.5"

Adjust the beta match and/or ground wire to tune R & X and the OAL for SWR.

Help Users
  • No one is chatting at the moment.
  • @ Roadstar:
    good morning to all :giggle:
  • @ ExitThirteen:
  • @ Roadstar:
    good morning everyone
  • @ magnuman:
    Hi from Down under New Zealand
  • @ Roadstar:
    how's it going, lost my internet for a bit in north texas