We have been receiving many questions from customers and other people about the 5/8 Co-linear Mamasita ver 4 Way Stacked Dipole.

The 4 way stacked dipole, if the dipole spacing is optimum, will have a gain of about 8.5dBi. The Mamasita is 7.8dBi, so it’s just about -0.7dB lower than the 4 dipoles. Now 0.7dB is virtually nothing, almost insignificant. But there’s also a couple of other things that should be noted when comparing Mamasita ver 4 way stacked dipole.



Gain 7.8dBi
Mounts to the top of the tower
True omni-directional
Requires no more than 0.5m (1.5Ft) at the top of the tower.
Center point of radiation 6.5m (21Ft) higher than 4 Way Stacked dipole.

4 Way Stacked Dipole

0.9 Wavelength (about 2.7m) Dipole Spacing Gain 8.5dBi
Mounts to the side of the tower
Not true omni-directional, the tower creates a small shadow to the signal
Requires 9.5m (31Ft) of tower space
Center point of radiation 6.5m (21Ft) lower than Mamasita

On optimized spaced 4 way stacked dipole needs 31 feet of tower space in length, in the middle of that length, halfway up or down at 15.5 feet, this is the maximum radiation point. Therefore at best the maximum radiation point is 15.5 feet below the top of the tower. Now given that Mamasita sits on top of the tower and the maximum radiation point is again halfway up the Mamasita, then the maximum radiation point of Mamasita is about 6 feet above the top of the tower. The difference between -15.5 and +6 is 21 feet. To conclude, Mamasita has at least a 21.5 feet height advantage over the 4 way stacked dipole. In terms of range or distance covered, this height advantage completely and by a large margin outweighs the small gain advantage of 0.7dB of the 4 way stacked dipole. Therefore Mamasita clearly is the winner in this regard.

The Mamasita prototype is going to Africa in next few days. A customer is going to install it, use and basically test it, not really for gain, as we know that’s good, but really for durability in diverse weather and climate conditions. We will give it 3 months of testing, if it’s all good, then we will go into full production and marketing of Mamasita.

Paul Hollings.

Customers like to send their old transmitters back to us for repair, but when you add up the shipping costs, this often costs more than just buying the new parts needed.

You can the buy the complete 100W block set from us as shown in the picture. This is completely assembled and tested and ready to drop in side your old power amplifier case, but make sure your power supplies are still good and reliable with the correct voltages. These 100W block sets are taken out of a fully operational brand new 100W transmitter, so all the screws and holes are in the correct places and then you have no hassle fitting the units when they are delivered to you.

If you need any further information don’t hesitate to contact us