ROHN GTMBLTelescoping Antenna Mast Base Plate
Made in the USA!
Telescopic Mast Base Plate is designed to provide base support for ROHN H50, H40, H30 and H20 Telescopic Masts. Use in both Temporary and Permanent mounting. Installation on top of small poured cement footer is ideal. Bottom of Mast Inserts onto Center Stake, Auxiliary hole can accomodate above-ground portion of Ground Rod exposed for bonding attachment. Bonding can be made by affixment to Mast. Consult NEC and Applicable Local Code for further guidance.
Related Products below for a suitable replacement with the EZ32 and EZ32A
3 Star Inc. EZ32A Heavy Duty Telescopic Mast Ground Mount
Made in the USA!
is designed to support and facilitate grounding for ROHN H20, H30, H40, H50 and Channel Master 1620, 1630, 1640, 1650, 1820, 1830, 1840, 1850 Telescopic (Push-up) Antenna Masts. Outer dimensions are 9 x 9 inches...
3 Star Inc. EZ32 Telescopic Mast Base Plate Mount
Made in the USA!
is designed to support and facilitate grounding for ROHN H20, H30, H40, H50 and Channel Master 1620, 1630, 1640, 1650, 1820, 1830, 1840, 1850 Telescopic (Push-up) Masts. Outer dimensions are 9 x 9 inches...
Remember those older AM/FM Portable Radios with the antenna that you extended by pulling it out? Or the Radio Antennas on older cars that would pop-out, extend and retract when you turned on the radio? This Mast isn't an Antenna, but it extends and retracts by hand in similar fashion. Available in 20', 30', 40' and 50' heights. All ROHN telescoping masts are pre-galvanized and come assembled with hardware. Erection is made by simply connecting guys and brackets to the attached unique heavy duty rolled edge guy rings and clamps, extend each section one at a time (starting with the innermost section), insert the locking cotter pins, rotating the tubes to a locked position, and tightening the clamps. Repeat the process on each successive section until fully erect.
The unique ROHN Products design features interior tube flanging combined with a double crimped exterior tube to produce a stronger and more stable joint than most common masts. This design exclusive also prevents the sections from accidentally pulling apart and allows disassembly by pulling each section out through the lower end.
Each section extends deeper in to the lower tubes than most other designs, adding still further to the stability of the structure.
H Series
This heavy duty series uses 1-1/4" 16 gauge galvanized tubing for top section. All other sections are 18 gauge.
Assembly
1. Secure base and anchors (sold separately).
2. Attach lowered mast to base.
3. Secure guy lines to the lower Guy Ring and attach to anchors. Align the mast vertically by tightening the Guy Lines.
4. Secure upper Guy Ring using the appropriate Mast Clamp to desired location on the upper Tube (see note 8 on page 10).
5. Secure appropriate length guy lines to the upper Guy Ring and let them hang.
6. Raise the upper Tube and inset the cotter pin. Make sure that the cotter pin is inside the notch in the inside tube.
7. Secure the cotter pin and tighten the mast clamp.
8. Secure appropriate length guy lines to the next highest Guy Ring, and let them hang.
9. Raise the next smallest Tube and insert the cotter pin. Make sure that the cotter pin is inside the notch in the inside tube.
10. Secure the cotter pin and tighten the mast clamp.
11. Repeat steps 8-10 until all sections have been raised and are secured.
12. Attach all hanging Guy Lines to their respective anchor. Align the mast vertically by tightening the Guy Lines. Make sure to work your way up the mast while tightening.
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