Hardware Choices?

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Re: Hardware Choices?

Postby SpaceManMat » Tue May 09, 2017 9:28 am

As with anything you design and build yourself, if there is an issue with it you will be held fully accountable ACMA especially if you use a Mobile frequency in the 900mhz range. If you have importeted anything (kit or ready built) please do make sure it has Australian firmware and is Austalian compliment. You can read the legal documents on the ACMA website.

Of course Blake has dealt with the ACMA and the manufactures and you can use it without worrying about compliance.
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Re: Hardware Choices?

Postby drew » Tue May 09, 2017 10:51 am

lorstin wrote:
kopius wrote:.............. eggtimers are STILL ILLEGAL IN AUSTRALIA and NEW ZEALAND. Because of this, further discussions about the use of these on this forum will be removed.....


Forgive my ignorance but what makes them illegal? :? I've just done a quick "google" and couldn't find anything relating to them being illegal.


The unlicensed ISM Band (900MHz) is different in Australia and the US. You're buying US configured radios that operate between 900MHz and 928MHz. Here in Australia the low end of the ISM band is licensed for mobile telephony usage. So 900MHz - 914.999MHz is licensed spectrum here in Australia. So if you're in Australia you need to ensure you ISM band radio only operates between 915MHz and 928MHz. What Blake's pointing to is the fact that Eggtimer products with ISM Band radios are configured for US usage and therefore will "stomp" on 900MHz-914.999MHz licensed bands. Optus and Vodafone own those ranges.

Apologies Blake, I never considered the Eggtimer radios would be doing this as I've never seriously considered purchasing one. But yea, unless one can guarantee that their Eggtimer radio is operating only in the 915MHz-928MHz range you're operating a radio illegally, regardless of the level of Amateur radio license you own. This is the reason why Blake organised with Greg Clarke from BRB to get an Australian BRB900 variant as the XBee ISM band radios they use can be configured to limit the frequency to Australian unlicensed spectrum.

I hope that helps.
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Re: Hardware Choices?

Postby drew » Tue May 09, 2017 11:03 am

Also, I just found this from the Eggfinder GPS Tracker User Manual.

The Eggfinder uses RF modules in the 902-928 MHz ISM band manufactured by Hope RF, model HM-TRP-915. They are intended to be used only in the United States. These modules have been tested by Hope RF to be compliant with the FCC Part 15 regulations for nonlicensed intentional emitters, and as such have been permitted to be imported into the US. However, Hope RF (at the time of this document) has not obtained formal certification with the FCC.


http://www.eggtimerrocketry.com/attachments/File/Eggfinder_Users_Guide_RevB6.pdf

Unless you can reprogram the Hope RF HM-TRP-915 radios to not transmit in licensed spectrum Blake's 100% correct and these radios would be deemed illegal as the radio interferes with licensed mobile frequencies. And I know from experience that stomping on ISM band spectrum can open you up to a $15k fine from ACMA. So it's probably best to NOT do it.
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Re: Hardware Choices?

Postby lorstin » Tue May 09, 2017 11:52 am

Thanks for clarifying that Drew.
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Re: Hardware Choices?

Postby kopius » Tue May 09, 2017 1:22 pm

Yeah, what Drew said! Thanks for writing that, it has been come up in the past on a few occasions and that is the first time I have seen the specific wording that it is designed for use in the USA.
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Re: Hardware Choices?

Postby Flying High » Tue May 09, 2017 2:21 pm

kopius wrote:I just have to chime in here from previous discussions, but unless the documentation has by some miracle been circulated without my knowledge, eggtimers are STILL ILLEGAL IN AUSTRALIA and NEW ZEALAND. Because of this, further discussions about the use of these on this forum will be removed.

Additionally, eggtimers will NOT be permitted at launches.

..............


If any body does any proper research on the matter you would find under Eggfinder FAQ,

"...I live outside the USA, can you sell it to me?

It depends on whether the 900 MHz band is available for unlicensed use in your country. Generally, we can ship to the USA, Canada (with some restrictions, email us...), Australia, and New Zealand, subject to some frequency selection limitations (i.e. Australia ships from 919-925 MHz since the lower frequencies are allocated for other purposes). ...."

So there is no basis for your statement and no basis for your ban.
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Re: Hardware Choices?

Postby drew » Tue May 09, 2017 2:52 pm

Flying High wrote:
kopius wrote:I just have to chime in here from previous discussions, but unless the documentation has by some miracle been circulated without my knowledge, eggtimers are STILL ILLEGAL IN AUSTRALIA and NEW ZEALAND. Because of this, further discussions about the use of these on this forum will be removed.

Additionally, eggtimers will NOT be permitted at launches.

..............


If any body does any proper research on the matter you would find under Eggfinder FAQ,

"...I live outside the USA, can you sell it to me?

It depends on whether the 900 MHz band is available for unlicensed use in your country. Generally, we can ship to the USA, Canada (with some restrictions, email us...), Australia, and New Zealand, subject to some frequency selection limitations (i.e. Australia ships from 919-925 MHz since the lower frequencies are allocated for other purposes). ...."

So there is no basis for your statement and no basis for your ban.


"Proper" research is one thing. Have you actually tested and confirmed that to be the case though? If not then I can tell you with 100% assurance that YOU'RE the one taking the risk here (and your club by proxy if they allow you to operate these radios untested). Above I highlighted how seriously ACMA takes these sorts of things. In my job I'm occasionally required to buy prosumer radios for point to point network connections when we don't want to pay for a proper fibre run. So we bought some Ubiquiti Rocket M900 point to point non LoS radios from a local supplier that assured us they were Australian compliant, pre-configured, and ready for "plug and play" usage. Well, they weren't, ACMA dispatched an engineer to Broome, he RDFed the interference to our site and threatened us with a $15k fine. Why? Because WE were the ones operating the radio illegally.

So unless you've independently confirm your frequency usage with something like an RF Explorer (http://rfexplorer.com/models/) you're taking a risk.

As such there is a real and understandable basis for this ban. Blake's just erring on the side of caution which is admirable, especially in this hobby.
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Re: Hardware Choices?

Postby Voyager » Wed May 10, 2017 5:20 pm

drew wrote:"Proper" research is one thing. Have you actually tested and confirmed that to be the case though? If not then I can tell you with 100% assurance that YOU'RE the one taking the risk here (and your club by proxy if they allow you to operate these radios untested). ...

So unless you've independently confirm your frequency usage with something like an RF Explorer (http://rfexplorer.com/models/) you're taking a risk.

As such there is a real and understandable basis for this ban. Blake's just erring on the side of caution which is admirable, especially in this hobby.


Being cautious is fine, but only if you apply this to ALL devices from ALL vendors - NOT just one cherry-picked for this shamefully biased treatment.

How many people have tested the spectral integrity of the units from any vendor/manufacturer that they employ in their rockets? As for a ban on any particular device, I would like to think that it was supported by some unbiased measurements or, at the very least, the appropriate documentation.

This could be a useful discussion on an important topic, but only if it is based on facts, rather than hearsay, or because "someone said so"! As for stifling discussion on a topic on the same basis, that's just counter to the purpose of a forum in which issues, even contentious ones, can be openly discussed.

This particular issue was discussed with Cris Irving of Eggtimer Rocketry. He is very aware of the Australian (ACMA) and New Zealand regulations and has been very careful to configure the Eggfinder telemetry to satisfy the local spectral requirements. All units shipped to Australia and NZ are firmware-limited to operate within 919 MHz - 925 MHz at 2 MHz intervals. He did acknowledge that some of his earlier manuals required updating to reflect the more recent modifications required to satisfy the various spectral requirements for international sales.

Just for the record, our group has two RF Explorers to monitor the output of any device we use over the 430 MHz, 900 MHz and 2.4 GHz bands.
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Re: Hardware Choices?

Postby Voyager » Wed May 10, 2017 6:12 pm

My apologies to Cris, that should read "Cris Erving of Eggtimer Rocketry."
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Re: Hardware Choices?

Postby OverTheTop » Wed May 10, 2017 6:24 pm

Cris at Eggtimer deliberately pitches the frequency 1MHz inside the band to ensure no infringement on adjoining airwaves. Australian units are limited 919-925MHz IIRC for our ISM band.

I have measured an Eggfinder TRS, and based on my measurements it fits nicely in the LIPD class license. I just need to confirm the power spectral density doesn't exceed the class licence limit. Since I don't do this for a day job (although I did purchase the equipment!) I have spoken to some people who do. I am in the process of organising measurement of an Eggfinder TRS at a NATA accredited lab.

Stay tuned for a definitive answer...
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Re: Hardware Choices?

Postby drew » Thu May 11, 2017 4:17 pm

Voyager wrote:Being cautious is fine, but only if you apply this to ALL devices from ALL vendors - NOT just one cherry-picked for this shamefully biased treatment.


I disagree with this statement on many levels. Firstly, the issue is only with ISM band radios. If you're in the 70cm or 2m bands you're fine as long as you're licensed to operate in those bands as those radios operate wholly within unlicensed spectrum. Secondly, there are ISM band rocket GPS tracking systems (the BRB 900 for instance) that utilise Australian variant radios. The BRB 900 uses Digi XBee radio modules that are specifically configured and compliant Australian models from Digi. Here's a link to the XBee Pro 900HP specifications sheet, you can clearly see the availability of Australian variants.

https://www.digi.com/pdf/ds_xbeepro900hp.pdf

The inclusion of Australian configured radios in BRB900 equipment came about because Blake liaised directly with Greg Clark to ensure the product conformed with Australian specifications. And whilst there are other ISM band radio telemetry systems commercially available I don't know anyone who's imported much less used them other than the Multitronix Lisa, which is itself a manufacturer configured Multitronix Kate for Australian usage. Given all that I do believe your allegation of shamefully biased cherry picking isn't supported by fact.

Voyager wrote:How many people have tested the spectral integrity of the units from any vendor/manufacturer that they employ in their rockets? As for a ban on any particular device, I would like to think that it was supported by some unbiased measurements or, at the very least, the appropriate documentation.


There's no need to test the spectral integrity of units if you can confirm the radio model used is an Australian compliant one. With the XBees you can, with the HopeRF modules included in the Eggfinder you can't. That's because there's only one HopeRF radio used across all Eggfinder products. Whilst the unit is software configurable it's the same unit across the globe.

Voyager wrote:This could be a useful discussion on an important topic, but only if it is based on facts, rather than hearsay, or because "someone said so"! As for stifling discussion on a topic on the same basis, that's just counter to the purpose of a forum in which issues, even contentious ones, can be openly discussed.


To my knowledge this forum is solely the property of Blake. I know it's free and there's no subscription or SLA. So in theory Blake could pull down the Ausrocketry forum tomorrow and none of us would have any recourse. Given that I don't really see this forum as some sort of nebulously protected free speech zone. If Blake decides he doesn't want something on the forum that's his prerogative.

Voyager wrote:This particular issue was discussed with Cris Irving of Eggtimer Rocketry. He is very aware of the Australian (ACMA) and New Zealand regulations and has been very careful to configure the Eggfinder telemetry to satisfy the local spectral requirements. All units shipped to Australia and NZ are firmware-limited to operate within 919 MHz - 925 MHz at 2 MHz intervals. He did acknowledge that some of his earlier manuals required updating to reflect the more recent modifications required to satisfy the various spectral requirements for international sales.

Just for the record, our group has two RF Explorers to monitor the output of any device we use over the 430 MHz, 900 MHz and 2.4 GHz bands.


So you're willing to put your hand up and stating as unequivocal fact that not a single original Eggfinder TX was purchased or delivered to Australia? Because from my reading it wasn't until the Eggfinder TX B6 version was released on 10 September 2015 that the capability to program frequency was even possible. Furthermore I'd be curious if you can state as unequivocal fact that no one hasn't purchased one of these newer units and had it delivered to a US address for inclusion into a larger freight forwarder consignment. I mention this as it's entirely possible that someone has a later variant that's a US configured model. According to the documentation the default base frequency is 915 MHz which in Australia is licensed spectrum. It also seems that these radios utilise a 2 MHz wide channel as the 9 user configurable base frequencies are in 2 MHz increments. So a US configured device would transmit over 914 -916 MHz in a default configuration.

Using the Wayback machine I can see the original Eggfinder release FAQ included NO mention of Australian frequency issues on 20 April 2014. In fact by how I read that FAQ all original Eggfinders were configured on 915 MHz.

https://web.archive.org/web/20140420030353/http://www.eggtimerrocketry.com/page26.php

I can also see the original post on TRF announcing the release of the Eggfinder on 4 February 2014.

http://www.rocketryforum.com/showthread.php?62624-The-Eggfinder-A-Low-Cost-GPS-RF-Tracking-System&highlight=Eggfinder

It wasn't until 10 September 2015 that the Eggfinder TX B6 version was released which even allowed the ability to modify the radio frequency. And even then it's a software configuration, not a HopeRF module supplied from the OEM as Australian compliant. So for 20 months the original units were available and not easily capable of being Australian RF configured, if at all.

Given all the above I can understand Blake's hesitancy regarding this hardware. And while you guys have two RF Explorers I don't believe QRS has one. I don't believe WARS has one. I can't speak to the other clubs around the country but I can say that if it was up to me and I couldn't independently confirm the units have either a) and Australian specific radio module or b) operating in appropriately unlicensed spectrum via third party hardware I wouldn't be comfortable with their usage.

Finally, putting my official ARMS Records Committee hat on I can 100% confirm altitude record applications relying on Eggfinder GPS data for said record will be denied given their reliance on inferior SIRFstarIV GPS chipsets. They're great for cars but terrible at reasonable velocity 3D movement.
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Re: Hardware Choices?

Postby Viking » Thu May 11, 2017 4:55 pm

drew wrote:...I don't believe WARS has one...

It kinda does, in a roundabout way :wink:
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Re: Hardware Choices?

Postby OverTheTop » Tue May 16, 2017 12:47 pm

OK. Time to put some actual measurement data on the output of the EggFinder product.

ACTUAL MEASUREMENTS OF EGGFINDER TRS
The unit tested is a recently purchased Eggfinder TRS, using the Hope RF HM-TRP-915 RF module.
The EggFinder is targeted to fit within the LIPD class licence, in the 920MHz ISM band, as defined by the ACMA. The relevant legislation can be found here:
http://www.legislation.gov.au/Series/F2015L01438
The relevant section is Schedule 1, item 58, Digital modulation transmitters. The requirements are:
    Frequency: 915-928MHz
    EIRP Max: 1W
    Power Spectral Density: <= 25mW/3kHz
Note that the versions of the Eggfinder shipped to Australia have band limitations imposed by the firmware that keep it more than 1MHz away from the edge of the defined band. This is to ensure that the requirement of all the emission falling within the band and not spilling into adjacent services. Overseas units are permitted to be used in Australia providing the frequency is set to be within our ISM band and no spectrum spills over into adjacent services.

SETUP
The Eggfinder TRS was plugged directly into an Agilent CXA signal analyser. The device under test was set to "Flight Mode" to commence transmissions.
SetupResize.jpg


PEAK POWER
Peak power was measured as 18.04dBm which converts to 63.7mW.
PowerPeak.png


POWER SPECTRAL DENSITY
PSD was measured next. Max hold function is used to ensure any higher power pulses are caputred faithfully. It is going to read higher than a result with a shorter averaging time (approximately 13dBm/95kHz higher in this case) which would be more like the actual emission density. This is a result of averaging the FSK modulated waveform over many scans.
The result is 21.8dBm/95kHz, or 151mW/95kHz. Working back to 3kHz (151 x 3 / 95) = 4.77mW/3kHz
PSDMaxHold.png


CONCLUSIONS
Maximum power was measured as 63.7mW, which is well under the 1W EIRP requirement.
PSD was measured as 4.8mW/3kHz, which is well under the 25mW/3kHz PSD requirement.
The Eggfinder TRS tested meets the criteria for the LIPD class licence as per the amended Radiocommunications Act 1992 (LIPD Class license 2015, compilation date 4MAY2016)
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Re: Hardware Choices?

Postby SpaceManMat » Tue May 16, 2017 6:45 pm

Thanks for the clarity OTT

OverTheTop wrote:Note that the versions of the Eggfinder shipped to Australia have band limitations imposed by the firmware that keep it more than 1MHz away from the edge of the defined band. This is to ensure that the requirement of all the emission falling within the band and not spilling into adjacent services. Overseas units are permitted to be used in Australia providing the frequency is set to be within our ISM band and no spectrum spills over into adjacent services.

I must stress this. Make sure you have the correct firmware loaded, if you have upgraded you LCD RX make sure it is the Australian firmware not the U.S. You can check this by going into the settings you should not be able to enter a frequency out side of 915-928MHz.

Also if you imported your own fixed frequency transmitter (which everyone who owns one is the importer) make sure it's in the allowable frequency 915-928MHz.

Otherwise you may use Mobile frequency that the Telcos paid big $ for, they will not be happy.
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Re: Hardware Choices?

Postby OverTheTop » Tue May 16, 2017 7:04 pm

I must stress this. Make sure you have the correct firmware loaded


It does not necessarily need to be the correct firmware. Even with the incorrect firmware loaded there would be no problems using the system if the frequency selected puts your system within our ISM band. The class licence states 915-928MHz for the ISM band. Any value between 916MHz and 927MHz (center frequency) will keep you within the LIPD class licence. These channel frequencies are 1MHz inside the band limits to ensure all emissions are kept within the band.

I have one of the earlier units that were not user programmable for frequency. I deliberately specified it to be 923MHz to make sure it was legal.

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