Microwave bands as far as the amateur radio community go, start at 1.2 GHz or 23cm. Although technically speaking this isn’t really microwave, It is the limit of the commercial ‘black box’ or radio you can buy from the toy shop. Some operators stop here and don’t go above this band for many reasons, but mainly equipment related. Yes it’s true you have to build things, and yes, it can be more plumbing than cabling, but the reality is, it’s a part of the spectrum that has its own unique rewards.
My interest in microwave has increased exponentially in recent times, mainly because I moved from the RF noisy inner city of Melbourne to the quite beach side town of Mount Martha. But it’s not just the move. My takeoff to the west and the north is unencumbered. With the exception of the odd tree and roofline, my line of site across Port Phillip Bay can in places be up to 60km.
If you’re keen to get into microwave, then the recommendation is small steps. Master one band at a time and find a mentor. This is so important. This can be someone from your local radio club or someone from one of the microwave groups on Facebook such as the VHF UHF Microwave – VK ZL Amateur ham radio. Chances are your mentor or local club will have the test gear you need to get your first project off the ground, and they’ll know how to use it. Watch and learn as I did, and add this skill to your existing RF knowledge.
Yes and No.
The microwave bands do have a reputation of being QSOs via appointment. Sometimes this can be true outside of field weekends, but once a group is established in your area, chances are you’ll be there on a nightly basis. This is the case in Melboune. 2.4 and 3.4 GHz has regular evening activity.
If you don’t already have 23cm, then this is a great band to start with. With the prevalence of the Icom IC-9700, there are quite a few stations on this band. There are also some repeaters and beacons on the band which come in handy for making sure everything is working. The SSB call channel is 1296.1 MHz and this is a place to call CQ. On field weekends and MADs, you find the action on 1296.15 MHz. This protocol can be replicated up the bands as well as down the bands too. In Melbourne there is more activity on SSB than FM.
If you don’t have the cash lying about to buy a transciever that supports 1296, then a transverter is what you need. This page is not the page to go into detail about everything you need , that’s what your mentor is for, but it’ll hopefully point you in the right direction. SG Laboratory in Bulgaria make a 23cm transverter which requires a 2m IF. Kuhne Electronics also make 23cm transverters. These are two of many companies that make this type of radio equipment and are provided here as they are popular in VK.
If you choose to go down the amateur microwave track, it’s all about short quality feedlines, antennas, and elevation. A lump of dirt will stop a signal dead in its track whether you run a watt or 100 watts. Think about your operational location. It’ll fall into two categories – home station or portable station. The physical terrain will be a determining factor of how far and who you can work. My tip – build to go portable. A couple of watts on a hill into a good antenna is going to kick some serious ass.
The last thing you want to do is destroy a transverter with too much RF as an IF stage. Most transverters use 2 or 3 watts drive as a maximum. Hi power rigs are a bit of a no-no too as they can have ALC overshoot transient at the beginning of transmission which can also take out a transverter. If you can, get yourself a Yaesu FT-817 or FT-818 qrp rig. These are the rig of choice by most microwaves today. Just have a look at the videos on Youtube. They also have 2m and 70cm. Most transverters use these bands as IF.
In Victoria, the microwave bands come alive during field days and microwave activity days. In and around Melbourne, there are dozens of stations to work in all manner of locations from home stations to field stations perched high on top of hills. My station is build for portable use.
Below is my thown together station comprising an FT-818, a 2.4 and 3.4GHz transverse, A 2.4 GHz gridpack and 3.4 GHz panel with a 5m run of CNT-400 cable.
The graphic below shows the electromagnetic spectrum and where the microwave bands fit into the whole scheme of things. Bands below visible light are nonionizing meaning the radiation does not cause cancers – well there has never been any evidence of this ever. This unfortunately is not the same for EMR above the frequency of light.
The graphic above highlights the microwave part of the radio spectrum.
The five most popular bands in VK are 23cm (1.2 GHz), 13cm (2.4 GHz), 9cm (3.4 GHz), 6cm (5.7 GHz) and 3cm (10 GHz). Once you’ve mastered these, the challenges continue with 12mm, 6mm, 4mm and even higher.
The calling channels on the microwave bands follows the structure of the lower bands. For example, the 2m and 70cm call channels are 144.1 MHZ and 432.1 MHz. This extends up the band so 1296.1 MHz, 2403.1 MHz and 3398.1 MHz etc are the call frequencies for SSB. During contests and Microwave Activity Days, the trend is to use .15 as a calling frequency. 3398.150 MHz for example.
SSB Call: 1296.100 MHz
SSB Contest Call: 1296.150 MHz
SSB Call: 2403.100 MHz
SSB Contest Call: 2403.150 MHz
This band can suffer from severe WiFi interference in densly populated urban areas.
SSB Call: 5760.100 MHz
SSB Contest Call: 5760.150 MHz
SSB Call: 10368.100 MHz
SSB Contest Call: 10368.150 MHz
This list isn’t a complete list by any stretch of the imagination nor is it an endorsement. I’m adding and subtracting links as I find them. Use these as a starting point. As a general word of advice, anything you find on eBay may not be as good as what you’d probably by from a reputable dealer. Having said that, there are eBay bargains to be had, but do your research and keep in mind you do tend to get what you pay for. Maybe ask in a Facebook group and see if others can share their experiences.
Kuhne make very popular transverters amongst other things. There are products that cover most amateur bands that you need a transverter for. They are pricy and have very expensive shipping. Kuhne is located in Berg, Germany.
The Mini-Kits Microwave Transverter Kits are ideal for getting on the higher microwave bands. They are all available as a basic Kit, or fully optioned including local oscillator, sequencer, RF Amplifier, and hardware etc. Mini-Kits is a South Australian company.
Mini-Circuits design, manufacture, and distribution of RF and microwave components and integrated assemblies. With design, manufacturing and sales locations in over 30 countries, Mini-Circuits offers 27 product lines comprising over 10,000 active models. Mini-Circuits products are used widely in commercial, industrial, and military applications.
The Mini-Kits EME166 Sequencer is very popular. It makes connection to other circuitry much easier due to a single 10 way header connector on the board. The Sequencer can be used to control Transverters with various component like antenna relays, power amplifier, or receive pre-amplifiers. It is also suitable for sequencing the switching of high power RF amplifiers with a transceiver. The circuitry incorporates both DC and RF sensed inputs that can be used to control the switching of the sequencer from RX to TX mode. The sequencer suits Transverters with either a single, or dual I/F connections. The circuitry uses a PIC micro-controller and MosFET switches, and has over voltage and current protection.