Graham Betts: It's ideal to mount the flowmeter in a vertical position, and it's also very important to have a reasonably straight piece of house going up to the flowmeter. Roughly 10 times the diameter of the entry point in length, and there's two good reasons for that: One is that if there's any residue left there it'll come down to the bottom of the hose, and another reason is if there's any air in the system, when the water or liquid comes up in a column there there's less likelihood of the air influencing the flow meter reading.

Bill Gordon: Ok one of the things I want to talk about when it comes to pulse width modulation or any system that actually runs a solenoid that opens and closes very quickly, is a style of nozzles that we're going to run on it and our choices and how that operates in conjunction with that duty cycle or the speed at which this opens and closes. So when we open and close a solenoid very quickly, we have difficulty running things like air induction nozzles.

You have to run specialist pre-orifice, a bit like your low drift types or standard flat fans on these, and you can see on this one we actually have a model number it's an 05 orifice, now for most of growers you know that might be running in the mid twenties they might choose an 025 or an 03 nozzle. If i put an 05 on there that means the percentage of time this is going to be on it's not going to be running continuously or a hundred percent of the time, so if I'd normally run an 025 and I put an 05 orifice on there it's going to be running about fifty percent of the time. That's one of the issues that we find with these is that if you put too big a nozzle on here that duty cycle or percentage of time that it actually stays open gets too low, so nozzle selection becomes very critical.

Now with this particular system you can run Wilga nozzles, but you also have the option to buy retro fitted caps and run T jets on. Like any other system you need to check that 1: it's going to give the litres per hectare, 2: it's going to give you the droplet size or spray quality you require, but the 3rd thing you need to think about with these systems and I can't emphasize that enough, is the percentage of time that it's going to be on or the duty cycle is absolutely critical.

Now for a lot of in-crop sprayers where we might be using a medium droplet, I would suggest to people to keep that duty cycle above sixty percent, so start as high as you possibly can don't let the machine slow down too much and the bottom end of 60, maybe fifty percent, but if you change the course droplets they're not going to distribute around as much behind the machine. You want to keep that duty cycle even higher.

So typically i'd aim again start as close to a hundred percent as i can, but in slowing down try not to let it get below about 70-percent with a course and so when you go around obstacles or the end of the field think about how you plan the paddock, with a couple of headlands in, treat it a bit like other sprayers that again is an added factor or duty cycle here which complicates things with pulse width modulation.

Bill Gordon: Spraying is large part of modern farming operations. When we're planning for spraying we need to think firstly at the whole farm level. So we need to consider things such as rotation of chemicals making sure that the products we're using last as long as they possibly can, also considering things like sensitive areas making sure that we're protecting those.

One of the key things we need to consider is making sure that every job is as effective as it can be. What that means for a lot of growers being able to plan right down at the paddock level. One of the things we can do to make sure that each job is as effective as it can be is firstly consider the mixing and filling operations.

Prepare a mixing plan which tells you what you're going to mix, the mixing order and make sure that it's loaded into the machine correctly. The second thing we can do is prepare a spray plan which highlights things like the nozzles we're using, controller settings and the things we should be looking at while we're spraying and make sure the job is going as well as it possibly can.

Once we've made all those plans and put things into place it's really important to keep good records of what you've done. This allows us to check back over time and improve our management.

This video appears in modules 1 and 9.

David Gooden: So we've designed this chemical mixing trailer to contain all the chemical that we need. We've purchased a mixing unit because we thought it had all the features that we needed to mix our chemical correctly. Some of the features with the mixing unit is that it has a cone tank and doesn't have any ledges inside which can retain chemical residue. It holds enough water for a full batch. It also uses the pump to suck the chemical and therefore not creating any air and foaming like a venturi system would. We run a clean water pump to keep the chemical and the clean water system separate. We run dry mate fittings in order to reduce the risk of chemical spill and we also use micromatic fittings to
suck from enviro drums.

The trailer has been designed to hold enough chemical for a whole day spraying,
we've got room for dry product, enviro drums and IBCs. We bring the clean water to the paddock in order to make it more efficient and on top of that we've brought the filling point of the sprayer to the front in order to make it quicker in the paddock to fill up.

Bill Gordon: In this introductory chapter to the GRDC funded application manual, we'll be talking about that the modules that are included in there so going through some of the different topics that will be covered, including aspects of planning for spraying operations, the operations themselves, the different types of spray systems available and how they work. So throughout the e-book you'll get good technical content on each subject area but we'll also provide short tips and there'll be pop-up video such as this one for you to look at.

Bill Gordon: There are a number of factors that will influence the outcome of any spray job. These factors take into account the target itself, the condition it's in, is it susceptible, is it going to take up the product, is it going to translocate it, your choice of adjuvant, which plays a big role, and whether the product can get into the plant quickly or not and how well it will be taken up. But also, we're thinking about what the product does when it hits a target. We're talking about translocation here.

Some products, when they land on the plant, will stay predominately on the surface. They might be things like protectant fungicides or some insecticides. Others will move into the leaf tissue and that's where they stay. Others can move upwards and outwards like many fungicides, some can move down in the plant, and how that product translocates within the plant has a big impact on your choice of application volume, so what sort of coverage you need. For instance, if the product only moves upwards and outwards, we may need to get spray right down through the canopy if that's where we need control.

So this chapter talks about target, timing, translocation, and all those factors that affect the outcome of the job, which will help growers with planning things like droplet size and application volume to get the best out of the situation.