[Amps] VHF all-mode and DC-to-daylight rigs

[Manfred Mornhinweg]

Joe,

> With amps or VHF/UHF radio I have always wanted to see a weather
> proof  black box to mount at the antenna and then a control
> panel/power supply for the shack.

It's not really convenient to place the whole radio at the antenna, 
because then the control cable would be more complicate. The best 
combination is to have all RF circuitry at the antenna, and run a low 
frequency or zero frequency IF (in analog or digital form) down to the 
shack, where the rest of the processing takes place.

Commercial microwave links often are set up in that way. Over a decade 
ago I was in charge of planning and installing such a radio link. The 
equipment I finally chose was made by Ericsson, and each station 
consisted of a dish antenna with a radio unit enclosed in a weathertight 
case, directly attached to the dish. A single coax cable ran down to the 
indoor equipment. That cable carried the low frequency signals, power, 
and control. The indoor unit would do all the rest.

We can homebrew similar setups in ham radio, but manufacturers can very 
likely sell larger amounts of complete radios housed in shiny boxes with 
as many knobs, buttons, meters and displays as will possibly fit on the 
front panel. Instead a gray box with one antenna attachment and one 
connector for a data/signal/power cable is much harder to sell.

This is a good source for high performance "black boxes" that are well 
suited for mounting in weatherproof boxes at the antenna feedpoints. 
There are preamplifiers, power amplifiers, converters and transverters 
for several bands. But apparently no complete antenna-mounted radio:

https://shop.kuhne-electronic.de/kuhne/en/

With these components you can use a VHF/UHF multimode radio, and even 
make use of its HF support if it has it, mount preamps and power amps 
for VHF/UHF at the antennas, and mount transverters plus amplifiers for 
all the higher bands at the antennas too. It's not hard to do, but a 
highly capable multiband VHF/UHF/microwave station quickly gets expensive!

In the times of Phase 3D, AKA Amsat-Oscar 40, I used an antenna-mounted 
13cm to 2m converter from this company, fed into a homebrew 2m to 6m 
converter, and feeding that 6m signal into my FT-736R.

When I bought the piece of land where I live now, I intended to set up a 
remote HF antenna system, with a legal limit amp and an RX preamp, at 
least, located at the tower. This would have been installed at the 
summit of a hill located within my property, having a completely free 
horizon all around. That summit is 150m away from the house, so it would 
have taken a long, buried coax cable carrying RF and basic control 
signals, with the AC power being carried by a separate cable. But I got 
too old, tired and lazy, before getting to the point of doing it, so it 
seems unlikely that I will ever do it. Instead I make do with modest HF 
antennas located by the house, on the westward slope of that hill.

Manfred


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