As I think that trying to cover and explain all about ARISSat-1 in a single entry would be too long, I’ll divide it into some parts so that in each part I can cover and explain better a different aspect of this great sat. In this first entry, and as its title says, I’ll give a general introduction to ARISSat-1 and to my experience with it, so let’s start!

ARISSat-1 is a project of the following organizations and agencies: ARISS (ARISS stands for “Amateur Radio in the ISS” and it is the international organization in charge of everything which is related with ham, or amateur, radio, in the International Space Station, such as school contacts for example. Currently there are two ham radio stations onboard the ISS, one in the Zvezda module and another in the Columbus module), AMSAT (also known as “The Radio Amateur Satellite Corporation”, it is an organization which has developed many amateur radio repeater satellites, and which launched the first of such sats, OSCAR, on December 12, 1961, only four years after the launch of the Russian Sputnik, which was the first satellite ever), NASA and Roscosmos (the Russian space agency).

ARISSat-1 is an experimental amateur radio satellite (or better said a microsatellite, given its dimensions of only 55 x 55 x 40 cm) developed as a follow-on project to SuitSat-1 (which in its turn consisted of a discarded Orlan Russian space suit which was deployed from the ISS and which was fitted with electronics and a transmitter box connected to an antenna located on the helmet, outside the suit and near a control panel which provided the interface for the astronauts to activate Suitsat prior to its deployment. More about Suitsat-1 in this PDF and also in this blog compilating audio recordings from it here). The development of ARISSat-1 started with that of SuitSat-2, but when an Orlan suit became unavailable for housing all the electronics and other elements (it had to be removed from the ISS to make space), the teams which were developing the new satellite moved on to the building of an spaceframe for this new sat so as to replace the discarded suit. The components designed originally for the Orlan suit, this is, the electronics in general and the control panel, were moved then to this new spaceframe. Note that as ARISSat-1 would be released manually by a cosmonaut of the ISS (as it happened with SuitSat-1), four big handles were included so that, despite the space suit’s gloves, cosmonauts could grip and handle it well.

Something that makes ARISSat-1 different from SuitSat-1 is that it does not only take its energy from a battery, but it also takes it from six solar panels (donated by NASA from a cancelled project, they dictated the overall size of the spaceframe) which provide energy for the operation of the sat and for recharging its battery when it is in the sunlight part of each orbit. These panels have also made possible that, after the failure of this battery a few days after the release of the sat (an unmodified Orlan space suit battery, intended for use in an Orlan suit for SuitSat-2) the satellite continues active despite the fact that this battery does not hold a charge anymore. Now, although when ARISSat-1 enters the eclipse phase of each orbit (or the phase in which it flies over the part of the Earth in which it is night time) it simply turns off because the solar panels stop providing electricity and the battery is dead, it performs outstandingly when it’s on sunlight and the solar panels are providing the energy for this great sat to work.

But what really makes ARISSat-1 special and different from all the rest of the satellites (at least for me! ) is that, similarly to Suitsat-1, since it was released from the ISS, it has been continuously transmitting a tremendously special audio transmission. In ARISSat-1, this audio consists of recorded greetings in different languages (including one in Spanish and another in Catalan! ), including a “Secret Word” in each language; an extract from the communications during the flight of Yuri Gagarin (the first human to go out to space); SSTV (Slow Scan TeleVision) pictures (!) in the Robot 36 format from one of the four cameras included in the equipment of ARISSat-1 (which can be easily decoded and obtained by just plugging the radio to, or playing the recorded audio of the pass through, the mic or line in input of the PC and using the free MMSSTV software for Windows); and spoken telemetry, in which the satellite actually reads to you (!!) the following values: MET (“Mission Elapsed Time” or the time since the last time the sat was powered up. With the battery failed this counter goes to 0 every time the satellite goes away from sunlight in each orbit); temperatures of both the IHU (“Internal Housekeeping Unit”) and the control panel (which is located on the outside of the frame of the satellite and which, like in SuitSat-1, provides the interface for the astronauts/cosmonauts to power it up); and also the voltage and the current from the battery!!! Certificates are available on the reception of secret words, telemetry and SSTV picture. ARISSat-1′s website says the following:

• Email the secret word/password, your name or group, date/time received,city, state, country and your email address to secretword@arissat1.org to receive a certificate.
• Email the voice telemetry data, your name or group, date/time received,city, state, country and your email address to tlmreport@arissat1.org to receive a certificate.
• Email a description of SSTV image, your name or group, date/time received,city, state, country and your email address to sstvreport@arissat1.org to receive a certificate.

ARISSat-1 also has a transponder, or radio repeater, which works in the SSB (Single SideBand) modulation and which is available for use by licensed ham radio operators (who can use ARISSat-1 as any other ham radio repeater satellite), a CW or Morse code beacon, and a BPSK format digital telemetry downlink, including that of the experiment developed in the Russian University of Kursk that measures the change in atmospheric pressure as the satellite descends as a result of the braking effect of the residual atmosphere existing in LEO, or Low Earth Orbit.

As it can be seen, ARISSat-1 is a very special satellite which I and other radio listeners and ham radio operators all over the world are enjoying a lot. The most special on ARISSat-1, the voice beacon can be heard on the frequency of 145.950 (FM modulation) as the satellite makes a pass over you and no expensive receiving material is required (I’ve been hearing it since it was deployed with just a tiny ICOM IC-R5 scanner and a recycled “rabbit ears” dipole TV antenna positioned in a “V” shape). For all of you who might want to try receiving it in one of its passes over your location, here are some links:

• www.heavens-above.com is a great website for predicting passes of ARISSat-1, the ISS, and a lot of satellites more. After registrating and introducing your location, it will calculate and the passes of the selected satellite over you in a very useful picture. Generally speaking the higher the elevation (angle between the path of the pass and the local horizon) of the pass is, the best the reception will be.
• www.stoff.pl is the website for downloading Orbitron, a satellite tracking application which even works offline! Needs updating the TLE files periodically as they lose precision with time. Although it also predicts passes, I don’t find it as precise as the Heavens-Above website for this purpose. But I find it great for knowing where ARISSat-1, the ISS or any other satellite is in real time and, in the case of ARISSat-1, for knowing if some passes will be with daylight or not because, as I’ve said above, its battery failed and ARISSat-1 is only powered up when it its on sunlight and the solar panels generate electricity.
• Download link for the SSTV decoder sofware, MMSSTV: http://www.qsl.net/kf6ypq/MMSSTV.exe. By using a male-to-male audio cable with 3.5mm jack connectors to connect your receiver to the mic or line in input of your PC, this program will translate the SSTV audio into a picture which can be saved as a normal .jpg or .bmp file, great! Another option, if the computer is not available during the pass to decode the SSTV in real time, is to use a digital audio recorder (I use as one of these my smartphone together with a homemade connector adaptor) to record the audio of the pass, then plugging the recorder to the mic or line in input of the PC, playing the recording and just letting MMSSTV decode the image from the recording. This works great too. Some advice would be to record in a .mp3 format instead of in .wav (or at least I’ve had better results recording in .mp3)
• And other webpages of great interest about this satellite are:
• Chips in Space, this is the blog of Steve Bible, one of the developers of this great satellite. I consider it essential to know all about ARISSat-1. Everything is here
• And naturally the official ARISSat-1 website, http://www.arissat1.org/v3/.

That’s all for now. In my next ARISSat-1 post I’ll detail its internal components to at least complement the Chips in Space blog which gives abundant information about it. So, stay tuned!!!

raptor22stealth

raptor22stealth

Nearly a week before we had a few attempts at starting it, but, despite a few explosions at the beginning, the engine refused to begin turning. It wasn’t till some days later that, being outside the building where we have the engine among other material, we heard a strange noise coming from it. We went inside… and there was the engine in full performance and operated by our 2nd course colleagues! Being the first time I saw an aviation engine turning it was a really exciting experience, noisy and windy too…!

Some interesting facts are that the engine was turning on only one magneto (thus having half of of the spark plugs, one per cylinder, inoperative). This made the engine want to stop when idling it. Throttling it up again solved the problem . Other fact is that the carburetor used by this engine did not correspond to it, although it worked quite well. The propeller was a wooden, four-bladed Sensenich which prevented the engine from running at excessive RPM’s during the run.

I didn’t have the HD camera with me, but I did record some video of the engine running with a Sony Ericsson k810i cell phone. Ok, not HD quality, but at least I got something acceptable. Enjoy!

Here’s the video of the joint pass of Discovery and the ISS…

…and here’s the one for Nespoli’s radio contacts. The schools contacted were Istituto Comprensivo di Verano Brianza — Scuola Media, in Verano Brianza on 03/23/11 and Istituto Tecnico Industriale Statale “Leonardo da Vinci”, in Pratola Peligna on 04/02/11:

More details in the video descriptions. Regards!

The package in the afternoon, just before being opened:

Opening it, we see everything inside it has been well protected all the way from the States to Barcelona via Frankfurt. Nothing to worry about for the moment:

With all the protections removed, we finally see what really matters, the content of the package. Nothing missing, everything OK:

This is what the package contained. A new 2.4GHz transmitter to replace the 35MHz one I used (with which I had serious problems, specially the lack of control over the helicopter when the servos started to make trembling movements and when the engines suddenly throttled without any movement of the throttle stick in the transmitter. I hoped that, with the 2.4GHz system, this problems I attributed to interferences in the PPM 35MHz transmission system of the old transmitter would disappear); a complete Xtreme Delrin gearing (for both the upper & lower rotors); two Xtreme electric motors (one for each rotor); a Xtreme 850mAh, 7.4V LiPo battery; a 2.4GHz 4-in-1 unit (which is composed of a receiver attached to a regulator/BEC/gyro unit, and everything enclosed together) to be used with the new 2.4GHz transmitter and to replace the old 35MHz one; and grip set spares (to replace in a near future the ones I have in the upper rotor, which do not hold the blades as firmly as when they were new):

After opening the box which enclosed the transmitter, I found it protected by two Porexpan covers and in good state. With it came also a printed manual:

The transmitter free of all their enclosings:

As the old 35Mhz transmitter, the power necessary to make it work is supplied by 8 1.5V, “AA” format non-rechargeable batteries, the same as the ones any other item like a radio uses. I don’t dislike it, but I would’ve preferred to see a NiMH or even a LiPo battery as the power supply for this transmitter… this would be more comfortable than having to change all the 8 batteries by newly bought ones (which you have to pay) when running out of charge…

Detail view of the battery compartment. A “charge” connector is also visible in the left side of the transmitter (or the right side viewed from the front). This is something I don’t understand: what makes a charge connector in a transmitter whose batteries are not rechargeable?…

In comparison: the old 35Mhz transmitter on the left, the new 2.4Ghz one on the right. In a first glance, the first thing that distinguishes the two receivers is the antenna. The 35Mhz one is the classical RC antenna: long and retractable (in my case it broke some time ago, and I had to use it a bit shorter than originally – perhaps that was the reason for the interferences, as I know that only one length is valid for a good transmission in a particular frequency). The 2.4Ghz antenna is way shorter, it is not extensible, but it can be oriented 90º to both sides (180º in total) and 90º in the vertical axis. It is similar to the antennas wireless routers use, as they often operate too in the 2.4Ghz band. Other details, such as the change in the presentation of the bottom & LED Voltage Indicator zones, are also visible:

Viewing in more detail both transmitters by their front parts, it is clearly visible the replacement of the crystal in the 35MHz one by a LED light indicating the operation of the module in the 2.4GHz transmitter, thus indicating that the placement of the module has not changed. In general, I think the only internal change in the transmitter, to adapt it to the new frequency, has been the module, as I find all the rest of its elements almost the same both in the 35MHz and in the 2.4GHz versions. I’ll see whether this suposition is true or not when I open the new transmitter…

The same transmitters viewed from their upper parts:

The back of both transmitters is exactly the same, so no changes in this area:

The power is supplied by the same in both transmitters: 8 “AA” non-rechargable batteries, as I’ve mentioned before:

The right side is exactly identical in the 35MHz and in the 2.4GHz versions. As I was saying some lines up this post, I cannot understand why is this charge port here if what goes inside the battery compartment are non-rechargeable batteries… A mistery…

No changes too in the left side of the transmitters:

Let’s move now onto the helicopter. That was the aspect of the internal structure which holds all the mecanical parts and the electronics, before installing all the pieces which came in the package. The motors are the original ones, they had enough power but I wanted more, so I bought the Xtreme ones, which would go in its place. And I had removed the 4-in-1 unit, having in mind its replacement:

The blades are the Airy Harden Blade II I bought at rchelicoptershop.com some time ago. Unlike the black original ones or the Xtreme ones, they are very flexible, which guarantees that, in case they contact or collide with anything while the heli is in flight, they will flex instead of breaking. And they work perfectly Since I bought them approximately a year ago, I’ve not replaced them. I even have two more of this blades unused

The internal structure together with the fuselage and the fuselage alone, before the modification:

Some time ago, I broke the entire tail gear in a hard landing, something that left a beautiful hole in the fuselage. To cover the appearances, I covered the hole with insulating tape:

That’s how the structure with the items in the package installed looks. As you can see, the Xtreme electric motors, having more power, have refrigeration holes to vent correctly the generated heat, which is greater than in the motors that came originally with the heli. The long, orange-coloured antenna attached to the 35MHz 4-in-1 unit has been replaced in this one by a tiny wire, which, although being almost invisible, is also very prone to break and separate from the unit (as once happened to me). Also, there’s an extra LED in the other side of the unit, belonging to the receiver component of the 4-in-1, which is used for binding indication purposes.

This is the new Delrin reduction gearing installed in the helicopter. I was tired of having to buy a new A gear (the lower, belonging to the upper rotor) every time I touched something with the blades due to the wearing of the gear teeth by the metallic pinions of the motors, so I bought this gearing, made of Delrin, which is a stronger plastic used in the gearing of piston-powered 3D helicopters. With this material I hoped this problems would end, and for the moment, and after some flights, I can say the entire gearing of the helicopter is still intact:

The original gearing now outside the heli. The damage in the A wheel is clearly visible: the plastic teeth were literally sanded by the metallic motor pinions when the blades touched something, stopped suddenly, and the motor continued to turn. This happened dozens of times to me, and, with the new gearing and my, for now, greater experience flying this machine, I hope I’ll be able to maintain the new gearing intact for a long time.

The B gear wheel, which moved the lower rotor through a hollow shaft which enclosed the upper rotor shaft:

It’s clearly visible it is a hollow shaft:

This is the new battery. I bought it for two reasons: to replace the original Esky one which was aging and losing effectivity, but also to provide more power to the Xtreme motors. And it works great! Never in a lot of time a battery had lasted so long to me… for the moment I’ve done as much as four flights on one charge and the battery still had energy for more. In comparison to the consumption of an entire charge per flight with the old battery, it’s been a great advance…

The heli with the battery inserted, viewed from below and from the left side. I added a bit of adhesive Velcro to the front left part of the battery so that it coincided with the Velcro in the battery compartment and secured the battery in flight, but it’s not completely effective as I’ve had to end abruptly some flights with the battery hanging from the helicopter in flight…

Finally, this is how the heli looks once fully mounted and updated with all the stuff in the package. With no tail gear and some patching in the nose, but it still looks nice:

And the receiver in its place:

All in all, all I can say is that I’ve been able to return the Co-Comanche to flight… and it flies perfectly! Even better than when I bought it new from factory… so it can be imagined I’m very happy of this purchase. Not only because it works great, but because the heli flies again! Something it didn’t do since a year ago or so… and I’m rediscovering it! I’m enjoying it as I had never done before… :)

Well, nothing more to say, stay tuned and good flights!

Yup! A small box has just arrived from Hong Kong this morning… but what does it contain? Well, it contains a pair of Futaba compatible receivers I ordered at HobbyKing, a 7-channel Futaba R617FS and a 8-channel OrangeRx  which, despite not being a Futaba original, works well with Futaba’s FASST system… or at least in theory.

The R617FS will go to a Multiplex Fox I’m converting to RC, and the OrangeRx will go to the toolbox so that I’ll have a receiver available for future projects.

But that’s not all… I’m also waiting for a package to arrive from California containing upgrades and spare parts for my E-Sky Co-Comanche coaxial electric helicopter, which is currently AOG (Aircraft On Ground)… and well, I hope I’ll be able to return it to the skies!

Stay tuned…

Update 12/25/10:

I’ve opened the package! Fortunately, everything was OK and in good state and the two receivers showed no signs of damage or deterioration.

Here are a few photos:

The two receivers outside the box for the first time! The OrangeRx at the left, the R617FS at the left. Got also a bonus sticker sheet for if I wanted to decorate the plane…

Here are them just as they arrived:

Out of their enclosures…

…and posing with one dollar cent and twenty euro cents coins for size comparison purposes:

Here we can see how the R617FS fits perfectly inside the front end of the Multiplex Fox:

The plastic air bag which has protected the load all the way from Hong Kong, is used here as a protection for my Graupner Elektro-Trainer’s tail… nothing is wasted!

Now I’m waiting for the American package to arrive… I’m looking forward to receiving it!

This is the very first entry in this brand new blog I’ve created. My idea is to make of it a personal space in which I’ll comment stuff on aviation (real, virtual, and RC) and also on spaceflight, because I think that, although it’s not directly related with aviation, it’s somewhat related with flight (and cause I’m a passionate on spaceflight, too! ).

Although my main language is Spanish, I’ll write here in English, which will enable myself to use this blog as a tool to improve my abilities on the language and to arrive not only to the Spanish-speakers, but all over the world!

Nothing more to say, I wish you all a Merry Christmas and… enjoy this blog! ;)