"Joerg" <notthisjoergsch@removethispacbell.net> wrote in message news:C%NTi.1058$%13.820@newssvr22.news.prodigy.net...> Hello Folks, > > After some Google searching and perusing the sites of the usual contenders > I only found one uC family that has serious on-chip RF transceiver > capabilities, the Cypress CYWUSB6953 and its brethren. rfPICs and others > usually only have a transmitter. > > Anyhow, the Cypress will only serve 2.45GHz but I need the lower UHF bands > for range reasons. Is anything coming down the pike soon or will that have > to remain a two-chip solution? > > -- > Regards, Joerg > > http://www.analogconsultants.com/Nordic has 8051 too.... I'm just developing a multi node system using it. Dirt cheap too!!! NRF905 433/868/915 freq.selectable. Loads of nice features. Development modules from South Africa about 14$ plus shipping. http://www.rfdesign.co.za/pages/5645456/Products/Wireless-Integrated-circuits/Wireless-ICs-transceiver-433-915MHz.asp Nordic's dev kit is loads of money.....
Micro controllers with UHF transceivers?
Started by ●October 24, 2007
Reply by ●October 25, 20072007-10-25
Reply by ●October 25, 20072007-10-25
TT_Man wrote:> "Joerg" <notthisjoergsch@removethispacbell.net> wrote in message > news:C%NTi.1058$%13.820@newssvr22.news.prodigy.net... >> Hello Folks, >> >> After some Google searching and perusing the sites of the usual contenders >> I only found one uC family that has serious on-chip RF transceiver >> capabilities, the Cypress CYWUSB6953 and its brethren. rfPICs and others >> usually only have a transmitter. >> >> Anyhow, the Cypress will only serve 2.45GHz but I need the lower UHF bands >> for range reasons. Is anything coming down the pike soon or will that have >> to remain a two-chip solution? >> >> -- >> Regards, Joerg >> >> http://www.analogconsultants.com/ > > Nordic has 8051 too.... I'm just developing a multi node system using > it. Dirt cheap too!!!26 Rand single qty isn't exactly dirt cheap. That's still $3.70.> NRF905 433/868/915 freq.selectable. Loads of nice features. Development > modules from South Africa about 14$ plus shipping. > http://www.rfdesign.co.za/pages/5645456/Products/Wireless-Integrated-circuits/Wireless-ICs-transceiver-433-915MHz.asp >The 905 doesn't have a MCU, that would be their nRF24E2: http://www.nordicsemi.com/index.cfm?obj=product&act=display&pro=80 Anyhow, Nordic is not very widespread in the US. Neither Digikey nor Mouser carry them. I need something that's more available here in North America.> Nordic's dev kit is loads of money..... >3000 Rand for their 24L01 eval kit? Ouch! What were they thinking? -- Regards, Joerg http://www.analogconsultants.com/
Reply by ●October 25, 20072007-10-25
> > 26 Rand single qty isn't exactly dirt cheap. That's still $3.70. > > >> NRF905 433/868/915 freq.selectable. Loads of nice features. Development >> modules from South Africa about 14$ plus shipping. >> http://www.rfdesign.co.za/pages/5645456/Products/Wireless-Integrated-circuits/Wireless-ICs-transceiver-433-915MHz.asp >> > > The 905 doesn't have a MCU, that would be their nRF24E2: > > http://www.nordicsemi.com/index.cfm?obj=product&act=display&pro=80 > > Anyhow, Nordic is not very widespread in the US. Neither Digikey nor > Mouser carry them. I need something that's more available here in North > America. > > >> Nordic's dev kit is loads of money..... > > 3000 Rand for their 24L01 eval kit? Ouch! What were they thinking? > > -- > Regards, Joerg > > http://www.analogconsultants.com/I meant the NRF 9E5 - 433/868/915. Volume pricing is ok. That place in SA is like a Mouser.... try their authorised distributors.........
Reply by ●October 25, 20072007-10-25
TT_Man wrote:>> 26 Rand single qty isn't exactly dirt cheap. That's still $3.70. >> >> >>> NRF905 433/868/915 freq.selectable. Loads of nice features. Development >>> modules from South Africa about 14$ plus shipping. >>> http://www.rfdesign.co.za/pages/5645456/Products/Wireless-Integrated-circuits/Wireless-ICs-transceiver-433-915MHz.asp >>> >> The 905 doesn't have a MCU, that would be their nRF24E2: >> >> http://www.nordicsemi.com/index.cfm?obj=product&act=display&pro=80 >> >> Anyhow, Nordic is not very widespread in the US. Neither Digikey nor >> Mouser carry them. I need something that's more available here in North >> America. >> >> >>> Nordic's dev kit is loads of money..... >> 3000 Rand for their 24L01 eval kit? Ouch! What were they thinking? >> >> -- >> Regards, Joerg >> >> http://www.analogconsultants.com/ > > I meant the NRF 9E5 - 433/868/915. Volume pricing is ok. That place in SA is > like a Mouser.... try their authorised distributors......... >It's a strangely organized company, no link on their home page where those "authorized" dealers might be. Even Arrow doesn't carry them. Nah, I'll stay with the mainstream manufacturers like TI. We can get their stuff almost anywhere. -- Regards, Joerg http://www.analogconsultants.com/
Reply by ●October 25, 20072007-10-25
On Thu, 25 Oct 2007 12:54:07 -0700, Joerg <notthisjoergsch@removethispacbell.net> wrote:>Paul Keinanen wrote: >> On Wed, 24 Oct 2007 13:34:29 -0700, Joerg >> <notthisjoergsch@removethispacbell.net> wrote: >> >>> Hello Folks, >>> >>> After some Google searching and perusing the sites of the usual >>> contenders I only found one uC family that has serious on-chip RF >>> transceiver capabilities, the Cypress CYWUSB6953 and its brethren. >>> rfPICs and others usually only have a transmitter. >>> >>> Anyhow, the Cypress will only serve 2.45GHz but I need the lower UHF >>> bands for range reasons. Is anything coming down the pike soon or will >>> that have to remain a two-chip solution? >> >> It would help if you had specified the country in which it should >> operate. The frequency bands, the power levels and duty cycles vary >> with country or at least with continent. >> > >As many countries as possible. Definitely US, Canada, Europe and in and >around the Gulf of Mexico, other cases also Asia. That leaves 433MHz and >2.45GHz. Or frequencies below 100MHz but there aren't any integrated >solutions for those.At least in Europe, the available bands would be 2.45 GHz, 433 MHz, 27 MHz and 13.56 MHz. Please note that in Europe, you might encounter 1-100 W amateur radio transmissions at the same or very close frequencies in the 433 MHz and 2.45 MHz band, so a good front end selectivity would be required. On 27 MHz 5 W CB transmissions could occur close to your frequencies and especially during the sunspot maximum, the HF frequencies may have strong signals from sources 1000-2000 km away. Also the 13.56 MHz band may have strong RFID signals. While the omnidirectional receiver antenna capture area is small on 2.45 GHz, this is not a problem on HF/VHF frequencies, in which a miniature receiver antenna is capable of receiving the band noise, but at to lower frequencies, the problem is the transmitter antenna efficiency. When the antenna dimension goes below about 1/10 wavelength, the radiation resistance drops quite low and the transmitter antenna efficiency is quite low.>> You said that the range was too short on 2.45 GHz. What kind of >> propagation environment do you have ? Free space, lot of thick trees, >> indoor or what ? > >All of the above, usually comms between a pod inside the house to >equipment outside. I guess our house would be the worst case, woodframe >construction with aluminum backed insulation inside the walls.Unless your windows are coated with some heat reflecting film, the UHF signal should easily pass through the windows.>> In a free space environment, the capture area of an omnidirectional >> receiver antenna at a higher frequency can get quite small, thus the >> receiver signal will be weaker. Also a lot of wet trees will attenuate >> the 2.45 GHz signal. >> >> On the other hand, in typical indoor situations and at the streets of >> a large city, there are going to be plenty of reflections and the >> propagation is more or less independent of the frequency. The shorter >> wavelength might even propagate more easily through narrow slits in >> air conditioning ducts etc. >> > >All I can say that around our house 2.45GHz does not work reliably at >all. <200MHz works excellent.If there is a wood outside your window (no reflecting houses on the other side of the street), you might not get much signal from a pod just below your window to a receiver inside your house. When using the license free frequency bands with legal power levels, one should expect 10-100 m reliable communication in typical conditions. While the system might work in some extraordinary situations for several kilometers (and this is used by the marketing droids) the typical distance is much less and the worst case situation might be less than 1 m. For instance the car key systems operating at 433 MHz might not work even if the key is just outside the windscreen, if there is a strong amateur radio transmission nearby somewhere in the 432-434 MHz range. Paul
Reply by ●October 25, 20072007-10-25
Paul Keinanen wrote:> On Thu, 25 Oct 2007 12:54:07 -0700, Joerg > <notthisjoergsch@removethispacbell.net> wrote: > >> Paul Keinanen wrote: >>> On Wed, 24 Oct 2007 13:34:29 -0700, Joerg >>> <notthisjoergsch@removethispacbell.net> wrote: >>> >>>> Hello Folks, >>>> >>>> After some Google searching and perusing the sites of the usual >>>> contenders I only found one uC family that has serious on-chip RF >>>> transceiver capabilities, the Cypress CYWUSB6953 and its brethren. >>>> rfPICs and others usually only have a transmitter. >>>> >>>> Anyhow, the Cypress will only serve 2.45GHz but I need the lower UHF >>>> bands for range reasons. Is anything coming down the pike soon or will >>>> that have to remain a two-chip solution? >>> It would help if you had specified the country in which it should >>> operate. The frequency bands, the power levels and duty cycles vary >>> with country or at least with continent. >>> >> As many countries as possible. Definitely US, Canada, Europe and in and >> around the Gulf of Mexico, other cases also Asia. That leaves 433MHz and >> 2.45GHz. Or frequencies below 100MHz but there aren't any integrated >> solutions for those. > > At least in Europe, the available bands would be 2.45 GHz, 433 MHz, 27 > MHz and 13.56 MHz. Please note that in Europe, you might encounter > 1-100 W amateur radio transmissions at the same or very close > frequencies in the 433 MHz and 2.45 MHz band, so a good front end > selectivity would be required. On 27 MHz 5 W CB transmissions could > occur close to your frequencies and especially during the sunspot > maximum, the HF frequencies may have strong signals from sources > 1000-2000 km away. Also the 13.56 MHz band may have strong RFID > signals. >There is also 40.7MHz but I've got to brush up what's available in Europe and other areas. That band works really well for longer ranges as long as your data volume is low.> While the omnidirectional receiver antenna capture area is small on > 2.45 GHz, this is not a problem on HF/VHF frequencies, in which a > miniature receiver antenna is capable of receiving the band noise, but > at to lower frequencies, the problem is the transmitter antenna > efficiency. When the antenna dimension goes below about 1/10 > wavelength, the radiation resistance drops quite low and the > transmitter antenna efficiency is quite low. >Depends on the power. We have two FRS radios (460MHz) with very short stubs. Theoretically they should be about 15cm long but they are maybe about 2cm. Yet I can talk to my wife when she is checking on a neighbor half a mile away, crystal clear voice signal. Out here that is necessary because we have a lot of wild animals running around and a call process on a cell phone takes too long when a bear barges around the corner.> >>> You said that the range was too short on 2.45 GHz. What kind of >>> propagation environment do you have ? Free space, lot of thick trees, >>> indoor or what ? >> All of the above, usually comms between a pod inside the house to >> equipment outside. I guess our house would be the worst case, woodframe >> construction with aluminum backed insulation inside the walls. > > Unless your windows are coated with some heat reflecting film, the UHF > signal should easily pass through the windows. >Well, it should but you can't ask it to do a 75 degree turn after passing the window ;-)>>> In a free space environment, the capture area of an omnidirectional >>> receiver antenna at a higher frequency can get quite small, thus the >>> receiver signal will be weaker. Also a lot of wet trees will attenuate >>> the 2.45 GHz signal. >>> >>> On the other hand, in typical indoor situations and at the streets of >>> a large city, there are going to be plenty of reflections and the >>> propagation is more or less independent of the frequency. The shorter >>> wavelength might even propagate more easily through narrow slits in >>> air conditioning ducts etc. >>> >> All I can say that around our house 2.45GHz does not work reliably at >> all. <200MHz works excellent. > > If there is a wood outside your window (no reflecting houses on the > other side of the street), you might not get much signal from a pod > just below your window to a receiver inside your house. > > When using the license free frequency bands with legal power levels, > one should expect 10-100 m reliable communication in typical > conditions. >100m would be fine, 10m would not.> While the system might work in some extraordinary situations for > several kilometers (and this is used by the marketing droids) the > typical distance is much less and the worst case situation might be > less than 1 m. For instance the car key systems operating at 433 MHz > might not work even if the key is just outside the windscreen, if > there is a strong amateur radio transmission nearby somewhere in the > 432-434 MHz range. >That's why I like lower frequencies. More range, usually. -- Regards, Joerg http://www.analogconsultants.com/
Reply by ●October 25, 20072007-10-25
> It's a strangely organized company, no link on their home page where those > "authorized" dealers might be. Even Arrow doesn't carry them. > > Nah, I'll stay with the mainstream manufacturers like TI. We can get their > stuff almost anywhere. > > -- > Regards, Joerg > > http://www.analogconsultants.com/http://www.nordicsemi.com/index.cfm?obj=menu&act=displayMenu&men=6 rubbish web site, I agree
Reply by ●October 25, 20072007-10-25
TT_Man wrote:>> It's a strangely organized company, no link on their home page where those >> "authorized" dealers might be. Even Arrow doesn't carry them. >> >> Nah, I'll stay with the mainstream manufacturers like TI. We can get their >> stuff almost anywhere. >> >> -- >> Regards, Joerg >> >> http://www.analogconsultants.com/ > > http://www.nordicsemi.com/index.cfm?obj=menu&act=displayMenu&men=6 > rubbish web site, I agree >Yes, I know, they are going through very few hand-picked smaller dealers instead of widespread modern distribution. Most of my clients don't really like that. -- Regards, Joerg http://www.analogconsultants.com/
Reply by ●October 25, 20072007-10-25
larwe wrote:> That comment should be taken with the appropriate sample of ionic > compound :)15.432 grams, I presume. -- One meter, to within 0.0125% accuracy (off by just under .005 inches): Three feet Three inches Three eights of an inch
Reply by ●October 25, 20072007-10-25
On Oct 25, 8:33 pm, clifto <cli...@gmail.com> wrote:> > That comment should be taken with the appropriate sample of ionic > > compound :) > > 15.432 grams, I presume.Canonically yes (and nice response BTW - I used to calculate hand- loads in grams and it freaks people out), however in this case I think you should consider the "grain" to be like a "grain" of propellant in a solid rocket motor; i.e. potentially very very large.
