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Hi Gain SPT500 Super Penetrator


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.
If they are not angled down, they will be soon.
It's just not the quality that was seen in the past.
Not that anyone would see an actual signal difference but when you live in adverse weather areas, strength matters.


Help Users
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  • @ Jim5570091:
    Maybe. I wasn’t impressed with just clamping the shield wire to the boom with a hose clamp. I built a l bracket with so239 female hubs. I posted a picture on the recent gallery’s.
  • @ Jim5570091:
    Well I cut the matching stubs down 1 inch at a time from about 20” down to 6”. Still no real changes.
  • @ 555 Central Missouri:
    Hello everyone, I have a old courier centurion pll 40 channel SSB, it has the extra channels and it has another switch that just moves the frequency down one channel on the dial, what is the purpose for this?
  • @ BJ radionut:
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