The shop station antennas are mounted on the clock tower at approximately 75'. Thinking about the movie, "Back to the Future"? Luckily, still waiting for a lightning strike to charge my flux capacitor. 
Wanted to move the launch point of the HF 80-10m end fed up near the top of the clock tower structure, but needed to stay clear of the copper sheeting as I didn't need any more odd counterpoise issues. Also wanted to keep the mast neat, hidden and presentable as viewed from the parking lot upstairs. Built an inexpensive 16' PVC mast and UNUN mount that members might be interested in.
Welded a roof mount base 1 1/2" x 18" length post to a 2 x 6 plate and added a shim sleeve 1 1/4" pvc coupler.
2" pvc pipe is the bottom 10' mast section slipped over mount and coupler shim.
2" to 1 1/2" rubber flex connector secures the top 1 1/2" pvc mast section sleeved approx. 4' inside the 2" bottom mast section. This clamping allows the mast to collapse to 10' if needing to transport.
Drilled a hole in a 1 1/2" end cap and used flat washers, split lock washer and extra nut to install an eye bolt. Glued the end cap onto the top of the mast.
Installed two 2" pipe hangers on the 9:1 UNAN to mount the enclosure onto the bottom mast section.
Here is a photo of the 9:1 UNUN mounted on the mast section with the antenna wire traveling vertical towards the top corner insulator. The antenna is flying in a sideways "L" shape. Approx. 11' vertical then 110' horizontal.
The mast is secured to the 2x12" fascia and rafters and the base is mounted to the roof and rafters with lag bolts.
Very little wind load and the end of the wire is attached with an insulator to a dacron rope/pulley/ weight to an oak tree at 65+ feet elevation. The top 16' of feedline is RG8x that transitions to approx. 120' of LMR400.
On an end fed antenna, the coax line is the counterpoise and have 7 ferrite bead clip-ons at 116', before the gas discharge tube and grounding before entering the structure (6 beads on the 2m/70cm feedline). The placement of the ferrite clip-ons and the coax length really affected the performance and the antenna analyzer readings on HF but not so much on the VHF/UHF dipole. Found a good use for an old PrimeStar junction box!
Found length and the point on the feedline where there is almost optimal matching and very happy with the SWR on 80/40/20/15/12/10. 80m is 1:1 at 3900 (near the evening net frequencies) and 20m 1:1 @ 14200. 1:4- 2:1 max on the other bands. The antenna tuner will make it work on 160 and 6m.
Wanted to move the launch point of the HF 80-10m end fed up near the top of the clock tower structure, but needed to stay clear of the copper sheeting as I didn't need any more odd counterpoise issues. Also wanted to keep the mast neat, hidden and presentable as viewed from the parking lot upstairs. Built an inexpensive 16' PVC mast and UNUN mount that members might be interested in.
Welded a roof mount base 1 1/2" x 18" length post to a 2 x 6 plate and added a shim sleeve 1 1/4" pvc coupler.
2" pvc pipe is the bottom 10' mast section slipped over mount and coupler shim.
2" to 1 1/2" rubber flex connector secures the top 1 1/2" pvc mast section sleeved approx. 4' inside the 2" bottom mast section. This clamping allows the mast to collapse to 10' if needing to transport.
Drilled a hole in a 1 1/2" end cap and used flat washers, split lock washer and extra nut to install an eye bolt. Glued the end cap onto the top of the mast.
Installed two 2" pipe hangers on the 9:1 UNAN to mount the enclosure onto the bottom mast section.
Here is a photo of the 9:1 UNUN mounted on the mast section with the antenna wire traveling vertical towards the top corner insulator. The antenna is flying in a sideways "L" shape. Approx. 11' vertical then 110' horizontal.
The mast is secured to the 2x12" fascia and rafters and the base is mounted to the roof and rafters with lag bolts.
Very little wind load and the end of the wire is attached with an insulator to a dacron rope/pulley/ weight to an oak tree at 65+ feet elevation. The top 16' of feedline is RG8x that transitions to approx. 120' of LMR400.
On an end fed antenna, the coax line is the counterpoise and have 7 ferrite bead clip-ons at 116', before the gas discharge tube and grounding before entering the structure (6 beads on the 2m/70cm feedline). The placement of the ferrite clip-ons and the coax length really affected the performance and the antenna analyzer readings on HF but not so much on the VHF/UHF dipole. Found a good use for an old PrimeStar junction box!
Found length and the point on the feedline where there is almost optimal matching and very happy with the SWR on 80/40/20/15/12/10. 80m is 1:1 at 3900 (near the evening net frequencies) and 20m 1:1 @ 14200. 1:4- 2:1 max on the other bands. The antenna tuner will make it work on 160 and 6m.
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