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Old 06-14-2010 | 10:14 PM
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Ryan Smith
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Default RE: Hobbico JM912 FASST JR Module

Jim,

I'm doing well, I hope you are also. I'm actually about to start the finish work on your ML that you sold Joey Hayes. Rob did a very nice job on the airplane, I hope I can do his work justice with the finish. I understand it you're doing quite a bit of heli flying? That's something that I've always wanted to get into, but I have too many interests, and not nearly enough time or money. I handed out quite a few of those shirts, and IIRC, they just said that I used JR 2.4 at Joe Nall. There wasn't anything about surviving on there, you may be thinking of the pun commercial that Futaba put out right before Joe Nall. I can't think of many environments more demanding than my Partner for RF signal noise/blockage (three of the four antennas being under carbon fiber, and the airplane being painted in metallic and pearl colors, with metal flake in the clear, as well as the CDI module being plugged into the receiver directly), and I had very low numbers after a full flight. I had less than 25 frame losses for each antenna, no fades, no holds. I'm not using special equipment, nor am I doing anything setup wise that JR or Spektrum tells people. I honestly think that the majority of the problems people are having are setup issues, with some being the fault of the equipment, be it either by damage, or by a QC issue. I would imagine that the latter is very small, but given the large influx of newer people in the hobby, they may be using crashed receivers because they don't know to send something in, or be very hard on their transmitters and other equipment.

Unless you know the full story, you can't conclusively say that a failure was due to DSM. I know there are a lot of people that have had problems with their airplanes taking a long time to boot up at huge events like this, but honestly, I don't think you can look at me with a straight face and tell me that surprises you. There are almost 1000 registered pilots at Joe Nall and I'm sure at any given time there were several hundred transmitters on, transmitting signals. How many "channels" are there on the 2.4 GHz band, 88 total? That's asking a lot out of a frequency spectrum. I also don't want to sound like an elitist, but tell me how many pattern guys or IMAC guys have you seen that have had problems with JR's equipment? How many of us had problems with Futaba's heat issue? Archie, you were living in north Mexico at the time, and I bet you didn't have the first problem did you? Given the fact that most of the people at SEFF, Joe Nall, and E-Fest are stick bangers that would plant airplanes into the ground whether they were on 72 or 2.4, and don't take the time to set airplanes up properly, I stand by my statement that it's largely setup issues. Very few crashes that I have heard about or had people come up to me at the JR tent at Joe Nall and describe to me couldn't be traced back to an error. There were very few that that had me, and others puzzled, and the people were offered to send their equipment in for a full diagnostic check.

Archie,

Steve told what I had read. I had always thought it was a true FHSS system, but someone posted a link to the FCC paperwork detailing it, and shows how it operates. I think Hitec has a true FHSS system, that hops about all frequencies, regardless of their strength. They both do the job well. There are some things that Futaba has with their 2.4 systems that I like, but it wouldn't be enough for me to want to use their module. I guess it just seems fundamentally wrong to use one brand's transmitter, and another brand's receiver. I never said that it didn't hop. I think you hit the nail on the head regarding the DSM-J issue, but remember, it's only in use in Japan because FHSS requires a lot less transmitting power than DSM does, and it goes against their country's regulations. Also, JR and Spektrum have invested a lot of money developing (and patenting) DSSS products, and it would not be a wise business move for them to totally abandon their business plan. The number of people they would gain from switching over from Futaba or other brands would be neglegable, to non-existant, IMO. You also stated that no system is perfect, I have to agree with that. There is nothing wrong with Futaba's system at all, consequently there is anything fundamentally wrong with DSM either. It's all in what you're accustomed to, and what you've invested yourself in.

I don't mean to pick fights. I'm glad that the (I'm hesitant to use the word) opposition to me in this thread have been Jim and Arch, and there has been intelligent discourse as a result. If anyone wants to talk to me directly, PM me and I'll give you my phone number. I would be more than happy to help anyone if they are having an issue with JR or Spektrum's equipment.