Spektrum/JR DSM2 test (Part 1)

This is part one of my look at the Spektrum/JR 2.4GHz DSM2 radio system, as implemented in a JR DSX9.

Please visit the webpage at: http://www.rcmodelreviews.com/dsm2flaw.shtml for more information on a weakness that I observed when testing the radio.

As the video you are watching shows, DSM2 is normally very resistant to interference, by virtue of its two operating channels -- even a powerful video transmitter can't knock it out at close range, so long as one of the operating channels is outside the inteference zone.

Please also watch part two of this review.

If you're a DSM2 user, feel free to share your comments on this review and my observations.

Category:

Science & Technology

Tags:

• RC
• planes
• radio
• control
• Spektrum
• 2.4GHz
• DSM2
• JR
• Japan
• Radio
• spread
• spectrum
• test
• review

[lindenphoto]

Thank you!! I have had at least 9 signal loss incidents over 4 years using Spektrum and didn't know about the issue you showed. My problem has been that I have so many receivers etc. buying into a new system would be so prohibitive but recently a Spektrum tech told me losing signal 9 times in 6000 flights isn't so bad is it after not being able to explain why my receivers seem to lose connection no matter what receiver/esc/batt at random times. It sucks not trusting your radio. Thank you!!

[MrJonezy82]

As for the bit were he say that need a lipo to be supplyed in tx would you want a lipo in ur £500 tx and then the lipo puffs up and burns ur tx as for the rx batt that just for setting models up

[VTOLmad]

Now I know what the '2' means - trhanks :)

[PHeMoX]

@AdrenaCo DSM2 doesn't, but the newer and future FHSS systems (probably?) will.

Looking at military grade FHSS gear, I am pretty sure they have already overcome the limitations of the brute force nature of the frequency hopping a long time ago. So who knows where this technology will go in the near future, especially as the 2,4Ghz band will become more crowded than ever before.

[alstu4u]

I would never use a 2.4 Ghz video transmitter while using a Spectrum radio. Just common sense. Go 900 Mhz and the range is better too, or just use a small video camera that are now available. I have been using SpectrumDx6 and DX7 for 4 years now and have never had a problem. I never range test, but now think I will start.

[e3dflyer]

During the video transmitter test it seems that

everything works fine, but when you

fly your FPV the results may be different?

As the distance from your radio transmitter

to receiver increases the receiver will hear

more of the video transmitter and lock the radio

out. Factually it's the same as getting stepped

on while talking on a CB radio.

[parnican]

Nice review! Just one question, TX is using two channels but what about RX without small satelite? E.g. AR500 full range RX without sattelite... i'm not sure about this case. Do you know if those RX without sattelite able "reading-using" signal from both channels? Or only one channel is used ?

[alexbin117]

Thanks. That's good to know that the JR system is not frequency hopping

[skelly194]

Your a clever guy and I like that you don't try to add any influence, wish I had seen these before I bought my DX6i. I don't trust them in any valued plane.

[macdugmac]

need more convinceing the old attak 4 futaba never let me down have heard some unexplaned non disputed piolets say the dx c an leave u with no explanation she didnt listen 2 wat i waz sayen limbo stiks