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Fistfulladirt
11-01-2022, 02:09 PM
Finally got this thing up in the air and more than doubled the height.

Fistfulladirt
11-02-2022, 05:08 PM
$265 delivered, Walmart.

Radiohobbyist
11-07-2022, 10:43 PM
A thing of beauty. ❤


$265 delivered, Walmart.

UPS Freight or dedicated truck line?

Fistfulladirt
11-07-2022, 10:53 PM
Was regular UPS.

mjd420nova
11-12-2022, 05:19 PM
They will stay up forever when properly guided. Many forget the middle, two sets is on the border line. I've seen the middle of the mast get pushed by the wind and it folded in half when not guided at the joints.

Cedar Mountain Radio
01-10-2023, 12:08 AM
They will stay up forever when properly guided. Many forget the middle, two sets is on the border line. I've seen the middle of the mast get pushed by the wind and it folded in half when not guided at the joints.
That's a big DITTO! Usually when there's more antenna - like a big 5/8 with 4 radials acting like a lever and reverse-folding the un-guyed center section, but it also depends on your area wind speed, 50mph will fold one with an I-10K but it might require 60-70mph to fold one with only a GainMaster, but I'm talking the older heavy thick-walled telescoping mast from the '70s, not this newer thin wall "aluminum-foil" mast they seem to be now.
I was a football playin', concrete workin' tuff-guy in my teens and couldn't flex the thick & heavy bottom section by squeezing it,
but I saw a newer mast last summer and couldn't believe I could flex it into an oval by squeezing the bottom section, and I'm lucky if I'm half a strong as I used to be.

I suggest 3 more guy cords at the 3rd section up - before you fold $265 in half.

Otherwise it looks good, and I'll wager greatly increased the GM performance!!

Cedar Mountain Radio
01-10-2023, 12:22 AM
Hey Fistfulladirt, are those guy lines metal or non-metallic cord?
Because if metal then you're freaking out the radiation angle of the GM and not getting anywhere near the performance that antenna can deliver.

I've had several of them and found it the worst antenna, aside from an A99, that I ever used - until I got it up to ~40' above ground, lost the metal guy wire for Kevlar-center Dacron guy line, and also removed the other antenna a 1/2 wave away from it,
then it jumped from S-7 to 2dB over S-9 to a guy 10 miles away - and gained as much in every other direction.

At first I hated the GM, then it became the best (600w) antenna I ever used.

Fistfulladirt
01-10-2023, 05:03 AM
Hey thanks for the reply Cedar. The guys are 3/16 Dacron polyester, at 16’ and 28’. So far so good in the winds this summer/winter. When I extend the mast to the full 42 feet in the spring I will definitely add a third set of guys. I’m not too sure about this antenna performance-wise but like you mentioned, it needs to be up there a ways.

Cedar Mountain Radio
01-10-2023, 09:48 PM
Well, I've run it at 41' against several well-known antennas such as a Sirio Vector 4K, 1970s vintage Penetrator, I-10K, Sister Oily, Shockwave and of course an Imax & Maco V58 and overall the closest in performance was the Vector and the full size metal 5/8 which were neck & neck though the Vector beat out the metal 5/8 locally, at greater distances the 5/8 came alive and beat the Vector, but the GainMaster was a full 2dB above the best at local and long distance, which translates to almost a full S-unit on a CB rig or 1/2 S-unit on a Ham rig. 6dB per S-unit is fictitious unless you're referring to old tube rigs like the Collins S-line where S9 was calibrated to 100μv instead of 50μv S9 calibration for newer solid state rigs.
...and the further away the station was, the greater the improvement by the GainMaster over the rest. Other than my own design, it's the best commercially available performer that I know of.
:thumb: on using non-metallic cord, and the Aramid fiber/Kevlar center Dacron cord does not stretch at all and is unbelievably strong - if ever you want to upgrade, though it ain't cheap!

mjd420nova
01-20-2023, 05:09 PM
The guy wires don't need to be non-metal. Using the ceramic eggs it can be cut and tuned to enhance a high takeoff angle for skip. Placing guys between ground radials can create what the transmitted signal sees as a ground element. They can also be used to capture an offending harmonic but it must be provided a path to ground. There can also be differences between the ground potential between a ground at the antenna base and a ground at the station. Don't rely on outlets, water pipes or lines from other services, establish your own ground system and don't mix them. And as with any outside antenna, lightning protection is essential.

Cedar Mountain Radio
01-21-2023, 02:08 AM
The guy wires don't need to be non-metal. Using the ceramic eggs it can be cut and tuned to enhance a high takeoff angle for skip. Placing guys between ground radials can create what the transmitted signal sees as a ground element. They can also be used to capture an offending harmonic but it must be provided a path to ground. There can also be differences between the ground potential between a ground at the antenna base and a ground at the station. Don't rely on outlets, water pipes or lines from other services, establish your own ground system and don't mix them. And as with any outside antenna, lightning protection is essential.

No ground or counterpoise is required because it's a center-fed 5/8 dipole with a balanced design.

Adding anything metallic anywhere in the near field of the GainMaster will destroy it's TOA and what you'll have left might rival the performance of an A99
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