That *could* make a difference. We have never had a glitch with our 7CAP's either, so perhaps the Rx is the difference.
Theres a really good web page explaining all about RC Radio Systems (including the difference between single and dual conversion here) http://www.torreypinesgulls.org/Radios.htm
The author of this page doesnt seem to think Dual Conversion is that big an improvement though. I would have thought the PCM error correction would cut straight through any noise picked up by the Rx though. As jake pointed out, if you can tell what is bad data and throw it out (PCM can), then you only need a few good frames a second to have reasonable control.
I have a spare R138DP receiver, Perhaps when Tim gets KO put back together, we can try his Rx and my spare Rx and see if there is any noticeable improvement. _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
Thu Apr 20, 2006 12:06 pm
andrew
Joined: 16 Jun 2004
Posts: 3110
Location: Castle Hill, Sydney. N.S.W
well my radio set is 6 channel 40 mhz and is double conversion, i have nevrer had an issue with it thus (its always been everything else that sucked) but reception and radio working has been flawless.
Single conversion radios seem to have alot more trouble from what i know
dual conversion sends double the signals so much better _________________ Andrew Welch, Team Unconventional Robotics
Thu Apr 20, 2006 12:43 pm
Spockie-Tech Site Admin
Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia
quote:Originally posted by andrew:
dual conversion sends double the signals so much better
Dual Conversion does *not* send double the signals.
It uses a two-stage "heterodyning" process on the *receiver* to decode the signal with two different "IF (Intermediate Frequencies) - 10.7mhz and 455Khz I think, rather than a single stage (conversion) of 455Khz.
By doing the down-conversion in two steps, it adds another layer of potential "filtering" for any spurious signals to get trapped in, before they make it through to the decoder section.
You can use the same transmitter with either a single or dual conversion receiver, because the transmitted signal is exactly the same.
There are techniques to reduce noise other than dual-conversion, but what will work best depends on the type of interference you are having to deal with.
Robot style interference is typically high strength broadband "hash" noise from the motors and ESC's switching. We are trying to pick out a single voice in a room full of people shouting. Normal RC'ers are more concerned about trying to hear a weak signal at long range - like your friend shouting from down the road).
*Edit - I just added some thoughts on Radio to a page on the Wiki so we can help out newcomers by pointing them there - http://www.robowars.org/wikka/StandardRadio - If anyone would like to add more info, feel free) _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
Thu Apr 20, 2006 1:05 pm
andrew
Joined: 16 Jun 2004
Posts: 3110
Location: Castle Hill, Sydney. N.S.W
thanks for the correction thar Brett.
Not sure what half them words mean but sounds about right.
All i know and care is that dual conversion is better then single conversion, plan and simple.
Gotta get spectrum down track though, WOOT. _________________ Andrew Welch, Team Unconventional Robotics
Thu Apr 20, 2006 2:00 pm
kkeerroo Experienced Roboteer
Joined: 17 Jun 2004
Posts: 1459
Location: Brisbane
Strange how no-one has mentioned what appeared to be radio interference in the Jolt vs Singularity match where both robots seemed (to me) to have control issues. Any one else notice this or am I dreaming. _________________ Get Some!!!
Secretary of the Queensland Robotics Sports Club inc.
Fri Apr 21, 2006 5:28 pm
andrew
Joined: 16 Jun 2004
Posts: 3110
Location: Castle Hill, Sydney. N.S.W
hmm, maybem could just be Jeff was driving bad as usual and nicks a bad driver nd weopon elay failed which may look like jitters
just kidding, not sure on that, its fuzzy
Nick, Jeff, what r your thoughts _________________ Andrew Welch, Team Unconventional Robotics
Fri Apr 21, 2006 5:30 pm
ffej Experienced Roboteer
Joined: 22 Jun 2004
Posts: 595
Location: Kurrajong, NSW
At first I put that down to radio issues, but when I went to charge the packs I was running during that match, they were intermittantly open circuit, and when Nick and I came out of the arena, both radios seemed to coexist happily. I do agree that we need to look into it more, the next Marayong event will tell I guess. _________________ Jeff Ferrara
fb@ffej.net
ffej.net
Fri Apr 21, 2006 6:27 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
I had motor problems and driver problems , the radio was going fine as far as I know. The Nomadio gets feedback from the reciever showing what the signal strength is at the far end so I see exactly what is going on. I think Jeff had connector problems on the RS80D, although it did look like radio reception to me during the match. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Fri Apr 21, 2006 6:30 pm
Philip Experienced Roboteer
Joined: 18 Jun 2004
Posts: 3842
Location: Queensland near Brisbane
Does anyone have futher experiences with the SS radios in robots worth mentioning? _________________ So even the rain that falls isn't actually going to fill our dams and our river systems
Wed May 31, 2006 7:58 pm
andrew
Joined: 16 Jun 2004
Posts: 3110
Location: Castle Hill, Sydney. N.S.W
well nick uses a 2.4ghz radio with jolt, glens using one in his all steel robot cobra, jeffs used one in singularity with no issues even with snapped radio antenna it still works no probs.
Alot of the US guys are using them now and no problems ive seen, one used it in his heavyweight bar spinner that is nasty as heck and defeated biohazard to name one and he says the world of it _________________ Andrew Welch, Team Unconventional Robotics
Wed May 31, 2006 8:02 pm
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
mine has never glitched. it just needs a fair bit of reciever battery power to keep them going (why cobra died against TWI). _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
Wed May 31, 2006 8:04 pm
ffej Experienced Roboteer
Joined: 22 Jun 2004
Posts: 595
Location: Kurrajong, NSW
Yeah, aparently they draw about double what the normal RX does, but the TX draws less.
I can vouch for the reliablity, the bit about possible glitching at brisbane earlier in the thread I linked to a dodgey pack, since it did the exact same thing in the match against cobra on the weekend . . . it started working again when I hit the pack. _________________ Jeff Ferrara
fb@ffej.net
ffej.net
Wed May 31, 2006 9:50 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
My Nomadio SS radio has been absolutely flawless - I couldn't be happier! _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Wed May 31, 2006 10:18 pm
ffej Experienced Roboteer
Joined: 22 Jun 2004
Posts: 595
Location: Kurrajong, NSW
quote:Originally posted by Nick:
My Nomadio SS radio has been absolutely flawless - I couldn't be happier!
The whole talking to you thing is just too cool _________________ Jeff Ferrara
fb@ffej.net
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
RoboWars Australia Forum Index
-> General Chatter
, the radio was going fine as far as I know. The Nomadio gets feedback from the reciever showing what the signal strength is at the far end so I see exactly what is going on. I think Jeff had connector problems on the RS80D, although it did look like radio reception to me during the match.
