900 MHz Spread Spectrum

[ezflyr]

Hi All,

I was wondering if anyone would care to speculate what Eagletree is using for the RF link in their new Seagull wireless telemetry units? I would imagine that they are off-the-shelf RF modules, but I haven't found anything in my searching that qualifies as "Spread Spectrum", at least in the price range these units will be selling for. Any thoughts?

John

[Mr.RC-CAM]

I believe it is an Apex Wireless design based on their Datahawk product. I am not sure if it is off-the-shelf. I suspect it has been customized for Eagletree.

RC-CAM

[tve]

Hi All,

I was wondering if anyone would care to speculate what Eagletree is using for the RF link in their new Seagull wireless telemetry units? I would imagine that they are off-the-shelf RF modules, but I haven't found anything in my searching that qualifies as "Spread Spectrum", at least in the price range these units will be selling for. Any thoughts?

John

This is speculation, but it appears that EagleTree holds the FCC grant certification for the radio equipment. From looking at the internal photos in the public records, I would say the Apex Wireless Inc. probably designed it.

http://www.eagletreesystems.com/Support/NewPDF/Seagull_User_Manual.pdf
http://www.apexwireless.com/


Regards,
tve

[ezflyr]

Hi,

Thanks for the replies! That Apex stuff looks really interesting. Any idea how much the Tx and Rx modules cost? I sent them an email but haven't heard anything yet.

Thanks,

John

[Mr.RC-CAM]

Their stuff doesn't look low cost. I suspect it is over $30 each for the Tx and Rx modules if purchased in OEM volumes. Probably two to three times that in sampe quantities. If you get a price quote then then tell us what you found.

RC-CAM

[billpa]

Hi All,

Our system is custom designed to work perfectly with RC models. We build the units in house, and they are not available elsewhere.

Regards,

Bill Parry
Eagle Tree Systems

[ezflyr]

Hi All,

Thanks for the replies! Unfortunately, Apex Wireless, which seemed to be the most promising lead, appears to be a defunct company?? At least they failed to answer any of my 4 emails or 3 telephone messages spanning about 2 weeks!! :confused:

John

[Mr.RC-CAM]

Does it matter who's module you are using? Maxstream has some very nice Spread Spectrum module offerings and is highly respected in the industry.

RC-CAM

[billpa]

Hi RC-CAM,

We integrated the wireless functionality into our own circuit boards, which greatly reduces cost of the entire system. Our flight telemetry/data acquisition system is $369.99, including everything. It would need to be at least double that if we used off the shelf modules, since the module manufacturer gets a large cut.

Also, using custom designed tx/rx means we could design them to work perfectly for modelers. FOr example, the very low power consumption of our on-board components means you can power it from your receiver battery and not have to have a 2nd battery.

Regards,

Bill Parry
Eagle Tree Systems

[AndyKunz]

Just had a visit from Xecom today. They have high and low power 900MHz stuff now. We were talking about competitors and they respect (but differ from) Maxstream.

Andy

[Mr.RC-CAM]

I totally understand the cost issues. It's nice to find suppliers that allow customization of their designs to support cost reduction strategies. Your choice to go with Apex was ideal for your situation (R/C stuff is a low volume market, no matter how you dress it up). Your street price is a very good deal for the technology involved.

BTW, my "Does it matter who's module you are using?" comment was actually in response to ezflyr's situation. Apex seems to be ignoring him, so the Maxstream solution might be a better route for him. Or, maybe not (I recall they have some awkward startup engr requirements). There are dozens of Spread Spectrum module vendors out there, so if one does not work out then on to the next. :)

RC-CAM

[billpa]

Duh. I thought that question was for me, but after rereading it clearly wasn't. Sorry. :-)

[Mr.RC-CAM]

I thought that question was for me, but after rereading it clearly wasn't. Sorry.
Billpa, your additional info was probably helpful to someone, so it won't go to waste. It's always interesting to hear from vendors when they offer technical insight to their designs. At least it is to me. :)

RC-CAM

[tve]

Does it matter who's module you are using? Maxstream has some very nice Spread Spectrum module offerings and is highly respected in the industry.

RC-CAM


Have you actually tested them? I did. They don't perform even CLOSE to their specs. They have virtually no interference rejection. If you want some, I have a whole drawer full of them.... got ripped on one of their "special deal months". I don't think they are so much respected in the industry..... I just think they are cheap and appeal to the greedy.

The two best in the industry are Microhard and Freewave. Nobody else is even in the same league. That I'm aware of.

I haven't had a chance to test the Aerocomm yet, but am looking forward to it. I expect it to beat the Maxstream in every way. Even cost.

Regards,
tve

[Mr.RC-CAM]

If you want some, I have a whole drawer full of them....
Which model do you have and how much do you want for a couple of them?

RC-CAM

[tve]

Which model do you have and how much do you want for a couple of them?

RC-CAM

I wasn't really serious, but if you are I will talk to my employer (who actually owns them) We have 19200 and 1200 baud modules. The price would be our cost (I'm pretty sure of that.) We have been planning that we would use them in some application that didn't require more than 50 feet. They work ok for that....

If you are serious, send me a private message with contact info and I will have someone contact you.

Regards,
tve