Foreign I Don't have a wide enough lens too get that continuously available. It's a hydraulic. It's all analog. So all analog.

In fact, the motors themselves. There's actually four four motors for Azimuth four for elevation. And so there. obviously I said hydraulic.

The motors themselves are relatively small. they're about so big. The gearing, however they go into, is Huge. So they're made by a company called Philadelphia Gear and Philadelphia Gear was commissioned in the 1960s after building so many Battleship turrets to Uh to provide the gearing for the deep space Network And so they're still still there now.

So I've never failed. So everything I just put a bit of oil in them and that's essentially the gearing and the braking system as well. So and the reason why we have four Motors on each to uh, talk to a counter talk? there's there's no whiplash, Got it? And I mean no. Whiplash So at all, even even when you're slowing at the maximum rate, and so the 70 meter here, it's a huge quarter of a degree a second at maximum, pick up your skirt and move.

So so when we're going down to point, it can take in the case of Voyager 2. So our Stow angle is probably about 17 degrees elevation and you'll see this. What we do is because the antenna has cables running from the dish all the way down to essentially the fixed point. We have wraps, so the dangle So and as we rotate, those wraps tighten, we have a physical limit.

So whether we're going clockwise or anti-clockwise where we have to say Okay this is as far as we go without pulling the cables out. we have to slow around. so we have essentially a null point which is a 17 degrees which allows us to travel North or South for most spacecraft without having to interrupt a track and then move around So 20 and that's 0.25 of a degree per second so on both Azimuth and elevation. So it can take 20 minutes to get to point and equally importantly you can take 20 minutes to get back to Stow.

So normally after we finish with the support we have a 15 minute buffer where we can return the antenna to its Stow point before we start the next support. So and you know after Voyager we could we could be having Cassini we could be having Mars Rising them. We have all the Mars spacecraft as well, so they've been Wave guides serve a lot smaller antenna. They can go up 0.8 so they're a lot faster.

There's a lot, a lot faster to point and a lot faster to Stow as well. Why does it have to go to a snow point? Well we have a number of reasons. One of them is for the wraps which I mentioned. so we we leave ourselves in an Optimum position.

So for going on to the next support, but also as far as moving the antenna to a Stow position where essentially is put straight up, it's good for weather. so when coming in, yeah, it's rare for us to shut down. So the limitations for the antennas are 80 kilometers an hour, right? So at 80 kilometers an hour, So if you went to Parks so you know you probably have 45 50 kilometers and the antenna automatically stows. Uh, here it hits 80 kilometers an hour and it's telling the supervisor you need to do something and the supervisor's tossing up.

Is it a gas? Does it Steady serve? Is that project commanding a critical command? That's a little bit different when you're tracking a spacecraft to just tracking service. A celestial object essentially. Does the wind affect light? Does it give you Jitter on the dish or anything? No. and that and that's down to to the motors.

So the torque anti-talk There's a lot you know if you look at. uh, how much anti-talk is there. There's very little and we can be pointing crosswind and we'll see no move physical movements at all. so it's not it.

I've never lost a spacecraft because of wind. Uh, I Suppose of you, look at the 70 meter and its lifespan is expand or extended on almost a continuous basis. There's no other resource like it. So and you know, even though projects can be supported on smaller antennas, it's data rates.

So the bigger the antenna essentially the the higher the data rate that can come down through it, the bigger the margins. So nobody unless you start a ring and array means that you know to actually get 170 meter. you're taking up almost our entire 34 meter resource. Which means there's no room for anybody else.

So at the moment, 2025 is, uh, what? they're giving uh, the 70 meter. but I can see that being extended again. Uh, years ago that the philosophy of the deep space Network changed so and they decided to. Oh and here we have the blow.

Just before movement, they started building jelly mold antennas. jelly. It's uh, around about 80 million dollars a piece. and they they hit across a design the Japanese had actually uh so built questions.

There's a 80 million bucks really is of a pop. And what they're trying to do now is they're trying to fill the DSN with 34 meter antennas. and when I say jelly mold, they're all the same design meal. Yeah, even the hardware within them I can show you I can without mounting an antenna.

Come on, come with me. Oh, this is our spare 400 kilowatt Klystron Uh, Strangely enough, with Klystron it's a very inefficient amplifier. and with inefficiency comes Heat So the jacket that you see is a water cooling. We have huge heat exchangers.

The sole purpose is to stop this thing from frying, saying that there's probably about as many safeguards on this as there is on a nuclear power station. so everything for every flow is measured to the gallon per minute We have arcing detection throughout as well. This thing went and started arcings. Uh, it wouldn't be a pretty sight so, but yeah, so all you see now is everything is cooling.

The waveguide feeds are here so you pump uh, very high voltage and I mean very high voltage and very high current and a little bit of drive. And this thing can generate 400 kilowatts of popular or RF power. You feed that through an antenna with a gain of 63 DB and I wouldn't want to be a bird flying over. So other than the being used as a storage room, so this is also the the control for the 18 kilowatts.

We actually have two separate transmitters on the 70 meter. Uh, so this one is the bread and butter transmitter. This is used on a daily basis and communicates from everything from New Horizons Uh, so I was on the way to the Kuiper belt to Mars anything closer than the moon 70 meter can't do the beams too too tight so but yeah so I've certainly sort of Mars and Beyond And in fact, so you start talking about K-ban this this antenna is only K Band capable on radio astronomy. The being wave guides now are K Band capable for spacecraft and we have a spacecraft called Lro which is a Luna.

When it points to Earth it has to point to us on K-band otherwise we don't receive it. So even on the spacecraft with K Band The Beam is narrow, but on a on a 34 meter it's It's narrower as well. So yeah, unless the two are pointing physically at each other, it's almost like a microwave repeater. So what does that mean? V Because we're rotating, the Uh itself would also have to track.

it. does it all the time anyway. So if if you look at any Orbiter so with a high gain antenna, so as it's orbiting, so the High Gain antenna has to track Earth because it's going around around objects you're talking about, that's correct. So it would have to say.

and if we have an issue and we go hang on it's a little bit low here and we'll talk to the project and say uh, where are you pointing and then I'll go darn northern hemisphere So so yes, So yeah, it's uh, it's it with K Band Point Not only the weather, but the pointing is far more crucial as well. Uh, the 400k sorry the 400 kilowatt. Uh. so what we're seeing is control.

You see the Klystron here. Obviously it's not down here with everything with RF and trying to pump the most out of it or receive the tiny bit of it, it has to be up the antennas. So if you look at the cones themselves, uh, either the cone or just just below it is is a place where the Lnas are the cryogenically called Low noise amplifiers, but they're also where the the Klystrons are as well for the transmitters. So very rarely will you have a waveguide path more than you know, four or five meters.

Do you have to maintain the cryogenic referrals and stuff like does that the cryogenic record systems do they require they? actually. So we've moved on. We used to use mazes and now we're using solid state hemps and I suppose a hemp is a good and a bad The Mazes were very narrow band, so same same temperatures, roughly about the same temperature within one or two Kelvin but there are very, very wide bands, but they were very susceptible to issues, temperature variations and and essentially the Spectrum could collapse and you had permanent magnets that you had to use to try and tune it back in again. Where the new hemps? They're really robust.

The problem is they're a very broad bandwidth and with broad bandwidths comes noise. So if you're looking trying to look for a little part of a spectrum and you have this noise that's covering essentially the entire Spectrum, So sometimes that can be an issue as well. but they're far more Hardy. They don't require tuning, they just chill them correct actually.

So if you look at what happens, uh, you've got the output of the LNA. The output of the LNA is straight away down converted to 300 Meg is so the whole the whole of the DSN works on 300. megaf. So then it comes down as analog to the Uh to the Operation Center where it's converted to digital.

So 300. Yeah right. So we've got the It was the fail programmable gated arrays so of universally used and we use the same system to Uh to convert it into digital. That's the the Mg set the Mg set so that's your motor generator.

Yep and its capacity. Oh I think it's about a hundred kilovolts. I'm not quite sure what the the amperage is, but if you look hard enough on the side so it'll tell you so. essentially you've got you've got the motor and the two generators here.

Current made in the USA Chris being waveguard's a General Dynamics Oh yeah, they're doing all the controls. Yeah, so they've done all the control systems served. So yeah, they got the contract for Dss35 and they've carried on through 36 as well. Actually so every antenna in the deep space Network or antennas that we interface with on other networks is given a number uh I Suppose fundamentally the the two two antennas made for very different purposes.

So if you look at Uh Parks it's a it's a radio astronomy telescope. It's minimum elevation is 30 degrees. So essentially the pencil doesn't have to be so high. It's uh, probably cheaper in construction.

but when you're looking at a celestial object that you know where it's going to be so you can just wait. it'll come within the beam. At some point you know you start looking at Zebos of which is essentially the uh, the the mountain dish and and that has a very tiny Bean But and it relies on earth rotation to actually for for the objects to come within in Focus Uh so that was one purpose this was made for spacecraft tracking. So so essentially when a spacecraft comes over our Horizon we want to be able to track it.

so we want to have full Horizon to Horizon coverage because the way it will work is of with us with a spacecraft uh support. So if you can't just wait for it to wander into your beam especially when Goldstone could be tracking it and the whole point of the deep space Network and where we are in Canberra and where the other two sites are is to provide that 24 7 coverage. So as a spacecraft starts setting in Goldstone it's starting to rise here. In fact there's an overlap.

so what that does is it allows us to pick up a spacecraft. the Goldstone is releasing and as it sets in Canberra it allows Madrid to pick up our spacecraft and it will will keep on going on. In fact, we actually have not only on the receive side, but we also have an Uplink transfer as well. Where the spacecraft is sitting dumb and happy in space, it's seeing a transmitted signal to it.

So and So it's coherent to worth. And what we do is we use a five second delay where we'll overlap our transmitters and as far as the spacecraft is concerned, it's transparent. So whether we're in Goldstone it makes no difference. So what we'll do is we'll tune to a common frequency.

So or in in the case of the new spacecraft. now we're continuously tuning Our Doppler. So as far as the spacecraft is concerned nowadays it's a stable frequency. Got it? So even if it's an Orbiter we know how how it's orbiting, We know it's Doppler shift as it's coming and going and we can predict to the hurt and so make sure that those those frequencies are precise and stable into the spacecraft.

Do you have to change that frequency over the course of a day's track or it used What we used to do is uh, and this is where they used to do it. So we're talking about 10 years ago. A lot of the spacecraft used to use what was called a Tsf which is essentially means nothing as far as an acronym. it just sounds good.

So something so set frequency, something set frequency and what it used to do. It used to have an average XA which was essentially the calculated Doppler throughout the day the Doppler shift and they used to average it over 24 hours, right? So so these average over the 24 hours when you went to get into the spacecraft, what you'd have to do. you'd have to sweep so you'd sweep and that would make sure that you Incorporated the spacecraft rest frequency so you'd grab it. You'd Sweep High You'd sweep low and then you'd stop at that Tsf and you knew that for a 24-hour period, you weren't stressing the spacecraft receivers as far as speed.

Now what we do is uh. with the new system, we're tuning continuously so there's a continuous ramp going up. Uh, so we'll do an initial sweep on that ramp and for the rest of the support, we're making sure that the spacecraft is seeing a frequency that's not moving actually so as far as referencing as well. So one thing is crucial.

not only so for the for a site, but also all the sites together, especially when it comes to Vlbi very long Baseline Interferometry is is timing. Timing is crucial. and so of the the timing systems that we have here, the Hydrogen lasers are probably the one of the most accurate timing standards in the world. Within the difference between here and Gallstone is probably about six microseconds, but we know it's six microseconds so we know what their difference is.

so so it means. Then we use a timing because it's really accurate for correlating between sites, but we also use that same timing standard to generate a frequency reference. So the whole site is has a hundred so Kilohertz pumped around it. So sorry.

100 Hertz 100 Hertz 100 Hertz Not 100 standard 10 megahertz? No, no auntie, No, it's not. It is right. So so do we have 100 Hertz pumping around and that's used as our frequency reference. A valley? Yes, it does.

Sorry, exactly. So when a position was looked for I suppose of tip and Builder was picked. There was two other sites within the Canberra area. so we had Honeysuckle Creek in Royal Valley.

Each one was given a different purpose. We had a Honeysuckle Creek which was the manned space stuff. That's the honeysuckle. Creek Did the moon landing, the actual walk, first steps on the moon? They did, they did observe, and we also had Aurora Valley which was uh, essentially the close Earth orbit stuff that was the Stdn satellite tracking.

Data Network Tidman Villa is always deep space Network And one thing that was common to all three was they were all in values. So if you look at where we are, there's a North and South Road into the site and you've got 30 kilometers one way in the other. But as far as cameras, because they're only 12 kilometers away, we're just over that. Hill.

But that Hill is a big stopper when it comes to RF And so and if we did have any RF, it'd be shooting straight over us. How does the well? That's it. It doesn't. It doesn't worry about it.

I Suppose when you look at it, it. doesn't. but we might be wanting to look that way. Oh so I Mean yes, if we're always pointing up, it does.

It will never get in. Yeah. But then you start thinking if something is really strong, you have a very narrow beam. but you have side lobes.

So so you've got this. You've got the narrow beam, You've got side lows silos. So the effective beam on a strong signal. This thing could be like 20 30 degrees.

So the side lobes are the issue. So and it means that you can get breakthrough. even though you're not pointing at something, you can get breakthrough. So so yeah, we've They decided that a hill was a good stopper, right? but you still overlap with the two other stations around the world.

even up the hills. Yes, so uh, the probably the one. We do have certain spacecraft obviously sort of when they're Rising so we'll have some that we can't We have a transmit mask so although we can receive down to six degrees. so we have a 10 degree limit for transmit and that's really just safe health and safety.

so we don't want to be a raiding a radiating anything that's on the Hills so that's the same. so there is a limitation serve as far as when we can can switch our transmitters on. Civil aviation is a big issue here, especially being so close to Canberra We have our own airspace. This is restricted airspace above all the way to 10 000 feet.

so you can fly if you want to Fly Above 10 000 feet and it doesn't concern us but anything lower we have to clear it and we work with civil aviations of if you wanted to come into it then you would have to make sure that all our transmitters are isolated as well. Actually I was mentioning that uh, it rides on a film of oil. Yeah yeah, only through three points. So it's not the we don't pressurize the whole bearing.

Essentially if you look at the antenna you have from the elevation down, you have those main Spas coming down and then you've got the ones coming from the elevation back and connecting where you see the essentially the little shed on the platform there the elevation axis. So there's three pads and the three pads are probably as tall as I am. There's six recesses again each one. each recess has its own pump.

2500 PSI lifts the the whole antenna and I Noticed there's some cockatoos up. There are birds. A problem. any uh, like they are actually not so much the cockatoos.

they're a feature. Starlings are stalling starlings. Uh, what we normally have. we have which have bird scarers which and I don't mean an individual walking around flapping his hands that we actually have uh, audible devices that generate squawks in the evening to try and stop the starlings from settling.

It doesn't stop them anymore. so they've We're trying to think of a another method of discouragement. So Well, yeah, the essentially the bird poo is an issue. The big 70 meter dishes.

Are they going to build any more? or would they rather build smaller ones with interferometry? Quite a while ago, there was a proposal by NASA to replace effectively a 70 meter with a field of little antennas. Unfortunately, it was an idea conceived by a radio astronomer. So, and it would be great on the receive side. As far as rank, you actually could combine all of them and make an effective big antenna.

but you don't get the same sensitivity do you? It would be close, it would be close to it. So yeah, if you had a feel of little antennas problem with it, you can't transmit so you know this. This thing has an enormous amount of gain on the transmitter and you say okay, well what effectively do we have to pump through a little antenna so to be the equivalent of the spacecraft and essentially would have melted antennas right? And then they start talking about, well, maybe we can start arraying the uplinks. So we actually, uh, have the spacecraft receive receiving in phase uplinks and they and it and it will appear to be bigger.

And so we've tried that with two antennas and we're not 100 successful with that. So the idea of a field of transmitting antennas is gone. So so that was out. So then they said, okay, well let's do small antennas.

That's where the 34 meters came into it and I said they're very much are a jelly mold antenna so it's a standard design we've had. Just had two new ones DSS 35 and 36. Uh, Gallstones having new ones Madrid's having new ones as well. Uh, what they want is a system which is relatively cheap to maintain the difference between a standard Cassegrain where essentially you're squeezing all the equipment as close to the horn as possible to reduce noise.

Suddenly isn't an issue with the beam waveguard, because what you're doing, you're forming the beam, the sub-reflector and with a series of RF mirrors, essentially taking it to a nice, air-conditioned room below. So suddenly you can be running maintenance tasks while the antenna is tracking. So suddenly, sort of Maintenance cut is cut as far as the cost and then you think, well, okay, you pick an efficient design as far as building. And as I said, so if you look at a 34 meter and it's around about 80 million Australian dollars so which is pretty darn good.

So somebody tried to cost that and gave up to the point where NASA said there will never be another 70 meter antenna. Wow, Wow. so it's so so yeah. What you're seeing, there is is a dinosaur that's heading to Extinction and we're just hoping that we can create an environment that we keep on prolonging it, but it's still the only game in town for some operations.

I presume it is. Well, I mean we're tracking Mars spacecraft under 34 meters. And as I said, so if that's what the spacecraft we're supporting aren't, the issue is what they require from the mission. For instance, if you want to bring down a high resolution picture like MSL it's taking all the time or casino is taking all the time you need that high bit rate.

and if it means then that I can bring down my dump data in two hours on a 70 meter. but I need four and a half Five Six hours, seven hours to bring it down on a 34. I know which one I'd be picking. So I'll be putting my So application into the schedule as soon as possible.

So so yeah, the projects love the 70 meter because it gives them bandwidth. That dish over there yeah is the Honeysuckle Creek that's the one that actually recorded the first Neil Armstrong's first steps. It was and so actually 26 meter. so it was brought.

it was dismantled from Honey Soccer Creek Brought here. Had a very long service here with the Stdn which is essentially the satellite tracking Data Network how does actually its own Operation Center as well. So uh, the shifts were split into two. You had your Stdn stuff and your TDN guys so used to drive in the cars and separate at the gate and they used to head down there that was retired.

Nobody wants to demolish it right? It's a it's a historic icon so and you know I look at it now and there's still a lot of nostalgia for me. So obviously for good many years of I was controlling that one as well. Uh, and I think it will sit there I don't think it's going to be used again. Uh, it's had a sister antenna from Aurora Valley and that ended up in Tasmania and that's still being used today.

So for radio astronomy, foreign.