Steam Deck Update

A few days ago Valve in a somewhat unusual move posted a partial teardown video of the Steam Deck, in particular showing off the battery and M.2 SSD, although the video was filled with various amusing warnings such as “taking out the screws will permanently weaken it”, which as any competent person will know is essentially bullshit, still I can’t blame them for it, as your average user has the intellect of a baked potato and shouldn’t be encouraged.

The overall design and build quality seems very good, in particular the controls appear to be modular which is going to make replacement easy, Valve also suggest they will be providing replacement parts, although this remains to be seen, I have no doubt there will be numerous third party options in any case.

Updated FAQ

Valve also posted an updated FAQ on the Steam Deck website, some things of particular note are it can be used as a game controller and includes a decent 1.5m USB-C charging cable, the screen is also 10 finger multitouch (although I have no idea why you’d put 10 fingers on it), the rest of it is fairly obvious stuff such as dual boot support, etc.

Developer Release

Valve have also been shipping early units to a number of game developers, as such there is a decent bit of game footage floating around on Twitter, it has been confirmed by at least one developer that a five hour battery life can be expected from a moderately demanding game, this is a good sign that most players will squeeze at least 4 hours out of it and much more with light games.

Conclusion

We’re now under three months before the first release units ship, I’m hoping more details are released soon about Steam OS as I have yet to see the anti-cheat improvements promised for EAC and Battleeye, it would also be interesting to try out the new interface which will eventually replace the big picture mode.

If you’ve not already reserved then you’re pretty much out of luck, most if not all regions have slots later than Q2 2022.

Steam Deck – The Future of Portable Gaming?

Valve Corporation (aka Valve Software), the makers of the popular Steam gaming platform announced the Steam Deck a portable gaming handheld on the 14th July 2021, reservations were opened on the 15th for a small fee, first batches are expected to ship in December 2021, although most people will probably receive theirs in early to mid 2022, reservations are currently only open to select countries and require a previously active Steam account, this is clearly in an effort to deter scalping which has plauged the GPU market.

Spectifications

The specifications of the Steam Deck have generated a lot of interest, it uses a 64 bit x86-64 CPU made by AMD using the Zen 2 architechture with 4 cores and 8 threads, this is only one generation behind the current Zen 3, this includes the RDNA 2 APU which has been proven to be very capable at running most modern games at or above 60 fps at 1080p.

Combined with 16GB of LPDDR5 RAM it’s expected to out perform nearly all current gaming handhelds, as with many of Valve’s previous products they are likely to be selling this at close to a loss, since the majority of their income comes from the Steam platform rather than the hardware itself.

It features a 7 inch LCD IPS display with touch, which is optically bonded to the front glass, some have questioned why it does not use an OLED display, but given how low they are pushing the price already I would say this is expected, given it’s an IPS panel it will still look great, the display resolution is 1280×800 giving it a 16:10 aspect ratio, this may seem a bit low resolution, but it’s a sensible tradeoff, RDNA 2 may be powerful but resolution is still a big framerate killer, an external monitor can be connected via USB-C DisplayPort if you really want a larger display.

Other features include a 6-axis IMU, bluetooth 5.0, dual band WIFI. stereo microphone and stereo speakers, connectivity includes a 3.5mm headphone/headset jack and a USB-C 3.2 Gen 2 port.

Battery Life

Valve have stated that it will last between two to eight hours from the internal 40Wh battery, this is more or less what I expected, ultimately how long you get depends on the games you play, very intensive games will naturally drain it faster than a simple game.

For charging and for continuous power it specifies a USB-C 45W PD3.0 power supply, which will likely be included with it, one thing that remains to be seen is if they offer replacement batteries, lithium batteries degrade over time so this could be an important consideration.

Steam Deck as a PC

Valve are advertising the Steam Deck as a portable PC, in many ways this is true as it is capable of doing anything a PC can do, to facillitate this Valve will be releasing an official dock for it which includes DisplayPort 1.4, HDMI 2.0, Ethernet, one USB 3.1 port and two USB 2.0 ports.

It can be connected to any monitor or TV up to 8k resolution, although if intended for gaming you should not exceed using it on a 1440p monitor as it may struggle to maintain a playable FPS, resolution scaling is an option for higher resolution monitors, although I tend to find this degrades image quality significantly.

It’s hard to say for sure how well it will perform in this scenario, we will need to wait for benchmarks to be sure, but certainly if you don’t have a PC or your PC is very slow this may be a viable solution.

Input

On the front, the Steam Deck has two analog joysticks with capacitive touch sensing, eight buttons, two trackpads (which Valve note are 55% more responsive than the Steam controller ones); on the top are two bumper buttons and two analog bumper buttons along with the power and volume buttons, on the rear there are four grip buttons, this gives a total of at least 20 assignments which can be adjusted with Steam input.

This should be sufficient for many games, but if you need more then using the USB port or Steam dock with additional controllers is an option.

Storage

The Steam Deck is available in three tiers, the bottom has 64GB of eMMC storage, the middle has a 256GB NVMe SSD and the top has a 512GB NVMe SSD, it has been revealed that it uses a standard M.2 2230 socket, so upgrading your memory should be possible, Valve seemed reluctant to advertise this as it opens the possibility of buying a low tier version and adding your own SSD, which is cheaper.

Because 64GB is such a small amount of storage I would not recommend it unless you plan on adding your own storage, it might do for some more basic games, but if you want to play large AAA games it will quickly become unworkable with some games exceeding 64GB as it is.

All versions also support additional storage via micro SD card, although this is typically quite slow making it the least desirable option, while we don’t have full specs yet it’s reasonable to assume that eMMC will achieve 300-400MB\s, NVMe 2000MB\s or greater, a good UHC-I SDXC card will give at best around 120MB\s.

Another final option is connecting external storage via the USB 3.2 Gen 2 port, although this kind of defeats the main point of the Steam Deck being portable.

Pricing

steam deck prices

The lowest tier version currently costs £349, the mid tier £459 and the top tier £569, this is extremely good pricing for the hardware you’re getting, the nearest competitor in performance would be the GPD Win Max which is around £584, but it’s not really comparable .

The highest teir is not really that great value for money, so I would suggest going for the mid tier, if you’re willing to install a SSD then the low tier is overall an excellent choice.

Software

The Steam Deck will be releasing with a new Steam OS 3.0, this time based on Arch Linux, along with the KDE Plasma desktop environment, this is not currently available but I’m hoping they will release this before the Steam Deck starts to ship.

Steam Deck does not place any restrictions on your software, you’re free to essentially do whatever you like, including installing other operating systems, although given hardware support this mostly means Windows or other Linux distributions, although I’m sure people will have fun getting obscure OS’s working on it.

This opens a lot of options besides your Steam library, certainly I expect emulators will become a popular choice allowing you access to many thousands of games, using alternative stores like Epic Games is also an option if you so desire.

The Steam Deck is fully capable of running most Windows only games using Proton, it’s not perfect but it works in most cases, the only real problem at the moment is that Proton will not work with some anti-cheat software, Valve have already confirmed that BattleEye and EAC will have support ready by launch but other anti-cheat software remains uncertain.

Suitable for Casual Users?

This remains a big question, and generally I would say no, even with the increasing support for Windows games there will be people frustrated at it for not running certain games, or software, at the end of the day it’s still running Linux and some Linux knowledge is preferable to get the most out of it.

Installing Windows is of course an option, but for casual users this may present too much of a problem, it would have been nice to see Valve offer a choice of operating system, maybe they will, it remains to be seen.

Overall Verdict

Overall while there are still many unanswered questions, what we have seen so far is quite promising, we will likely get more details as we get closer to launch, for now you should reserve it as soon as possible before stock runs out or you end up waiting a long time, reservation is only £4 and you can get it refunded if you change your mind.

TinySA Spectrum Analyser Review

The TinySA is a low cost portable spectrum analyser that also functions as a signal generator, this is a true spectrum analyser that has a wide dynamic range and can measure a signal up to 960 MHz, it is developed by Erik Kaashoek and has open source firmware but not hardware.

It features a 2.8″ LCD color touchscreen in a 90×58 mm plastic case, it includes a rechargeable internal 650mAh battery for portable use but can also be powered and recharged by the included USB C cable, it has two SMA female ports for input and output and a jog switch for additional control.

Hardware

The TinySA is primarily designed to operate between 0.1 to 350 MHz, input and output for this range uses the low SMA port, this includes a 0-31dB attenuator (1dB steps), the minimum RBW (Resolution BandWidth) is 3 kHz giving it a reasonably good signal resolution, it has a maximum of 290 measurement points when not connected to a PC and overall RF performance is decent, keeping in mind this is portable and low cost.

The high port operates between 240 to 960 MHz and is lower quality than the low port, but still quite functional for many usage cases, this also includes the calibration signal generator fed from a 30MHz TCXO which is used to calibrate the level of the low port, a single level attenuator is included which varies from 22.5dB to 40dB depending on frequency, image suppression of this port is poor so it should be considered as a free extra rather than the main purpose of the TinySA.

Overall the hardware is exceptionally good for the price, but you should not expect similar performance to a modern spectrum analyser, it is however more than good enough for most applications that do not require high precision measurements.

Included with the package is two SMA male cables and a SMA female to female adapter, as well as a small SMA extendable antenna, although mine broke pretty quickly.

Signal Generator

The TinySA also functions as an excellent signal generator, note that this cannot be used at the same time as the spectrum analyser function, the low port can put out a 0.1 to 350 MHz sine signal between -76 and -7dBm, it can also perform a frequency and level sweep as well as AM, Narrowband FM and Wideband FM modulation making it extremely versatile.

The high port can also put out a signal between 240 to 960 MHz square wave, with a level between -38 and +16dBm, as well as frequency sweep and narrow and wide FM modulation, it’s important to note that being a square wave there is a very high harmonic content which easily exceeds 2GHz making this capable of producing a signal in the many GHz range, as such it should never be used to drive a power amplifier and antenna.

Harmonic output at 1.75GHz with FM modulation

Software

The software is extremely well made and easy to use, and for the most part reliable although I have had the occasional freeze, even with the small touchscreen it’s quite usable by those possessing fat fingers, the firmware is easy to update and impossible to brick due to mistakes making it very user friendly.

Software for PC use is also available for Windows and limited use with Linux, this can extend the number of measurement points to many thousands giving even more resolution.

High port connected to an antenna and PC, 3000 points

Overall

I’m very impressed by the value for money offered by the TinySA, normally for a spectrum analyser you’d need to pay several hundred pounds, to get a reasonably similar alternative for $50 is huge, even though it’s more limited, the functionality is perfectly good for many usage applications such as verifying the output of a radio, tuning filters, RFI and EMI testing and much more, as such any electronics lab should have one of these as a must buy item.

Beware that there are some poor clones being sold out there that may perform much worse, an official list of sellers is available on the wiki.

Thrustmaster TCA Quadrant Airbus Edition Review

After having endless issues with my Saitek X56 HOTAS I decided to pick this up, it’s available at the relatively low price of around £100, I got mine from scan.co.uk.

Build Quality

The overall build quality is very decent, even though it’s mostly plastic it feels like good quality plastic that does not creak and bend when pressure is applied, the paint job is of high quality and I suspect will last a long time.

It’s quite compact which works well on a cramped desk and despite it’s low weight it doesn’t move much on my wooden desk, a mounting hole is provided if needed, the throttle leavers move quite smoothly to the point when I had to increase the tension adjustment quite a bit, but once done it feels good just don’t over tighten it or you will break it.

The only real negative I can find is the mechanism to link the throttles together, it’s possible with a bit of pressure to move one throttle slightly but it isn’t generally a big deal in practical usage.

Functionality

Four push buttons are included, two on the throttle levers, and two on the lower pedestal, there is also two switches and a three position switch, not a lot but it’s sufficient, it’s possible to link two throttles together to give yourself four throttle levers which is ideal for something like the A380.

Thrustmaster also sell an addon module which includes speedbrake, gear, flaps, parking brake and more for around the same price, although at the time of writing this there was no stock available.

Another useful feature is it allows you to plug in a Thrustmaster T.Flight rudder pedals helping to save your usb ports, speaking of USB it uses a type C connector (on the product side) which is a nice touch.

The throttle includes detents which are found in the real Airbus aircraft, these can be disabled by removing four screws and switching some plastic parts around, this could be a bit annoying if you switch a lot so I would have liked to have seen a different mechanism to do this, the included detent range is also not ideal as it leaves little room for the manual thrust range, fortunately someone has already produced a mod to fix this minor issue if it really annoys you, personally it seems ok to me.

The thrust reverser can be disabled to allow you usage of the whole range if desired.

Overall

Given the relatively low price this is a good throttle that offers some degree of extension if you need more controls in future, I’ve used it a fair amount in MSFS now and it appears to work just fine, some complaints about certain functions not working appear to have been resolved, overall I have no hesitation in recommending this.

Plotting Orbits – Part 1

This article has been reworked on 21 March 2021
- Fixed error in first equation

Using the orbital equation it is possible to plot the orbits of planets, moons and other objects to a reasonable degree of precision, this however only works for visualising orbits that are relatively stable or at an instant in time.

Accurate orbit data (ephemeris) can be obtained from NASA JPL Horizons system, in this case we’re interested in the Kerlerian elements rather than the state vectors which are more suitable for simulation.

In this part I will only be plotting the orbit in two dimensions, I will cover the plotting of orbits in three dimensions in another part.

Plotting an ellipse

Most orbits are elliptical, although some are relatively close to circular such as the earth-sun and geosynchronous satellites, none are exactly perfect and will drift over time due to orbital perturbations, the following equation can plot a circle, ellipse, parabola or hyperbola depending on the eccentricity value, if you are not familar eccentricity is a unitless value that determines the shape of an orbit, 0 is a circle, between 0 and 1 is an ellipse, exactly 1 is a parabola and greater than 1 is a hyperbola.

To plot in polar form the equation is:

$$ r = \frac{a(1-\varepsilon^2)}{1+\varepsilon \cos \theta} $$

Where a is the semi-major axis of the ellipse (the radius from the focal point) and ε (epsilon) is the eccentricity of the orbit, this can be converted to rectangular form with:

$$ x = r \cos \theta $$

$$ y = r \sin \theta $$

The maximum and minimum distance from the focal point can be calculated with:

$$r_{min} = \frac{a(1-\varepsilon^2)}{1+\varepsilon}$$

$$r_{max} = \frac{a(1-\varepsilon^2)}{1-\varepsilon}$$

An example of the results can be seen below:

Rectangular form

If you’d rather plot directly in rectangular rather than polar you can use this equation:

$$ \frac{(x+F_1)^2}{a^2} + \frac{y^2}{b^2}=1 $$

Where b is the semi-minor axis, and F1 is one of the two focal points, in this case the one on the right is chosen to match up with the polar equation which uses the right focal point also, the semi-minor axis can be calculated with:

$$ b = a \sqrt{1- \varepsilon^2} $$

And for the focal point:

$$ F_1 = \sqrt{a^2 – b^2} $$

Since it’s centred on the focal point F1, the centre of the ellipse is at (-F1,0) whilst F2 is at (-2*F1,0), it’s important to note that this equation does not work with an eccentricity equal or above 1.

Alternative equation

The alternative form given in the Wikipedia article is somewhat more complicated but yields the same results, in order for this to work you need to know the velocity at periapsis.

To calculate the velocity you can use the vis-viva equation, using the distance to periapsis:

$$v =\sqrt{\mu \frac{2}{r_{min}}-\frac{1}{a}}$$

Where μ is the gravitational parameter:

$$\mu = GM$$

For example for earth:

$$v =\sqrt{1.327184555 \times 10^{20} \frac{2}{1.47095 \times 10^{11}}-\frac{1}{1.49598023 \times ^{11}}} = \approx 30287.94 \text{m}/\text{s}$$

The equation to plot the orbit is:

$$r = \frac{\ell^2}{m^2\mu}\frac{1}{1+\varepsilon\cos{\theta}}$$

Where m is the mass of the secondary body and the angular momentum ℓ is:

$$\ell = m v r_{min}$$