Mike,

Sounds very interesting. Do you use straight or electronic key?

Andrew Palm of Wisconsin (also retired) used a Launchpad to make an Iambic Keyer. See:

http://e2e.ti.com/support/microcontrollers/msp43016-bit_ultra-low_power_mcus/f/166/t/58090.aspx

Regards,

OCY

--- In m..., Mike Staines wrote:
>
> Thanks, Al.
>
> In my use, the modulation will be CW (Morse code). Since morse is a low
> duty-cycle mode, I will have plenty of time to process things during the
> "key-up" intervals (between dits and dahs).
>
> Even using Bi-Phase Shift Keying (BPSK) should only require a couple of
> clock cycles.
>
> Appreciate your help!
>
> Mike
>
> On Wed, Jan 12, 2011 at 7:01 PM, OneStone wrote:
>
> >
> >
> > Its viability depends on how much other processing you might need to do,
> > at 200kHz and 16MHz clock frequency you have 80 clock cycles per
> > modulation cycle, plenty to handle another interrupt if both are kept
> > short and clean. So you could implement your modulator using the timer
> > hardware and potentially handle some simple input devices at the same time.
> >
> > Al
> >
> > On 13/01/2011 9:53 AM, Mike Staines wrote:
> > > Thanks, Al!
> > >
> > > So, it seems to be viable as a signal generator for the frequencies that
> > I
> > > am concerned with.
> > >
> > > I will post my code for sharing as I advance this project.
> > >
> > > Slightly-off-topic: With the MSP430 as an exciter, about 5 or 6 common
> > parts
> > > for an amplifier and 50 ft of wire you can make a small license-free
> > > transmitter and antenna that can be heard many hundreds of miles away.
> > Quite
> > > a few people nationwide (U, S,) are playing there. I am just the first to
> > > think of using the MSP430 as the exciter.
> > >
> > > Mike
> > >
> > > On Wed, Jan 12, 2011 at 1:26 AM, OneStone>
> > wrote:
> > >
> > >>
> > >> Try working it out. 16MHz is the maximum clock frequency. so figure out
> > >> the fastest way to switch I/O using different addressing modes perhaps,
> > >> and then add 2 clocks for the jmp. generally you would do this with the
> > >> XOR instruction and select the output bit to be addressable using the CG
> > >> registers. This would give the following:-
> > >>
> > >> L1:
> > >> XOR.B BIT0,&P1OUT ;4 CLKS
> > >> JMP L1 ; 2 CLKS
> > >>
> > >> SO 12 CLOCK CYCLES OR 1.3333mhZ AT 16mHZ CLOCK AND 1mHZ AT 12mHZ CLOCK
> > >>
> > >> AL
> > >>
> > >> On 11/01/2011 4:59 PM, Mike Staines wrote:
> > >>> Hi, all!
> > >>>
> > >>> I am a hobbyist and I picked up two Launchpads to start learning uPs in
> > >> my retirement.
> > >>> If I were to program the chip that came with the launchpad to just loop
> > a
> > >> program that toggled the state of a pin (i.e. pin = !pin), what is the
> > >> minimum reasonable, ball park, SWAG, frequency should I expect to see on
> > the
> > >> pin? Can I get at least 1 MHz?
> > >>> Thanks, in advance,
> > >>> Mike
> > >>>
> > >>>
> > >>>
> > >>>
> > >>>
> > >>>
> >
> > >>>
> > >>> Start a New Thread

On Tue, 11 Jan 2011 18:42:01 -0500, you wrote:

>On Tue, Jan 11, 2011 at 12:04 PM, Hugo Brunert wrote:
>
>> >> Depends what you expect to "SEE"
>>
>> The square-wave output will be used to drive a class-D RF amplifier for a
>> FCC "Part 15" (i.e. License free) transmitter. Assuming I can get at least
>> 160 - 190 Khz pulses from it...

Appendix E, starting page 91, for "Wireless Audio Devices?"

http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-10-16A1.pdf

Jon
Start a New Thread

Hi....

Since OCY asked the question here I'll reply here but I don't want to go too
far off topic for the forum. So, if anyone is interested I take messages
directly at:
m...@email.com

I use a straight key myself (i.e. an old-fashion telegrapher's key, as
opposed to the more ergonomic Iambic key) but this project is for a beacon,
that is to say an unattended transmitter that just sits on a frequency and
transmits an identifier 24X7. I will incorporate the dit/dah sending with a
timer and look-up table..

Others then use DSP techniques to receive the signal and send a report of
their reception. DSP can find a signal when the ear hears just static. There
are about 25 similar stations throughout the US and Canada and the MSP430
will replace a PC and some homebrew hardware.

I am also a ham, and president of my local club. If I can get this project
going I think I can get some of the members to build MSP430 projects of
their own.

Regards,
Mike

On Wed, Jan 12, 2011 at 11:30 PM, old_cow_yellow
wrote:

> Mike,
>
> Sounds very interesting. Do you use straight or electronic key?
>
> Andrew Palm of Wisconsin (also retired) used a Launchpad to make an Iambic
> Keyer. See:
> http://e2e.ti.com/support/microcontrollers/msp43016-bit_ultra-low_power_mcus/f/166/t/58090.aspx
>
> Regards,
>
> OCY
>
> --- In m... , Mike Staines
> wrote:
> >
> > Thanks, Al.
> >
> > In my use, the modulation will be CW (Morse code). Since morse is a low
> > duty-cycle mode, I will have plenty of time to process things during the
> > "key-up" intervals (between dits and dahs).
> >
> > Even using Bi-Phase Shift Keying (BPSK) should only require a couple of
> > clock cycles.
> >
> > Appreciate your help!
> >
> > Mike
> >
> > On Wed, Jan 12, 2011 at 7:01 PM, OneStone wrote:
> >
> > >
> > >
> > > Its viability depends on how much other processing you might need to
> do,
> > > at 200kHz and 16MHz clock frequency you have 80 clock cycles per
> > > modulation cycle, plenty to handle another interrupt if both are kept
> > > short and clean. So you could implement your modulator using the timer
> > > hardware and potentially handle some simple input devices at the same
> time.
> > >
> > > Al
> > >
> > > On 13/01/2011 9:53 AM, Mike Staines wrote:
> > > > Thanks, Al!
> > > >
> > > > So, it seems to be viable as a signal generator for the frequencies
> that
> > > I
> > > > am concerned with.
> > > >
> > > > I will post my code for sharing as I advance this project.
> > > >
> > > > Slightly-off-topic: With the MSP430 as an exciter, about 5 or 6
> common
> > > parts
> > > > for an amplifier and 50 ft of wire you can make a small license-free
> > > > transmitter and antenna that can be heard many hundreds of miles
> away.
> > > Quite
> > > > a few people nationwide (U, S,) are playing there. I am just the
> first to
> > > > think of using the MSP430 as the exciter.
> > > >
> > > > Mike
> > > >
> > > > On Wed, Jan 12, 2011 at 1:26 AM, OneStone > 40bigpond.net.au>>
> > > wrote:
> > > >
> > > >>
> > > >> Try working it out. 16MHz is the maximum clock frequency. so figure
> out
> > > >> the fastest way to switch I/O using different addressing modes
> perhaps,
> > > >> and then add 2 clocks for the jmp. generally you would do this with
> the
> > > >> XOR instruction and select the output bit to be addressable using
> the CG
> > > >> registers. This would give the following:-
> > > >>
> > > >> L1:
> > > >> XOR.B BIT0,&P1OUT ;4 CLKS
> > > >> JMP L1 ; 2 CLKS
> > > >>
> > > >> SO 12 CLOCK CYCLES OR 1.3333mhZ AT 16mHZ CLOCK AND 1mHZ AT 12mHZ
> CLOCK
> > > >>
> > > >> AL
> > > >>
> > > >> On 11/01/2011 4:59 PM, Mike Staines wrote:
> > > >>> Hi, all!
> > > >>>
> > > >>> I am a hobbyist and I picked up two Launchpads to start learning
> uPs in
> > > >> my retirement.
> > > >>> If I were to program the chip that came with the launchpad to just
> loop
> > > a
> > > >> program that toggled the state of a pin (i.e. pin = !pin), what is
> the
> > > >> minimum reasonable, ball park, SWAG, frequency should I expect to
> see on
> > > the
> > > >> pin? Can I get at least 1 MHz?
> > > >>> Thanks, in advance,
> > > >>> Mike
> > > >>>
> > > >>>
> > > >>>
> > > >>>
> > > >>>
> > > >>> > 40egroups.com>
> > >
> > > >>>
> > > >>> Start a New Thread

On Thu, 13 Jan 2011 15:01:19 -0500, Mike wrote:

>>> Appendix E, starting page 91, for "Wireless Audio Devices?"
>
>Thanks, Jon.
>
>Fortunately, we do not send audio (generally). And The frequencies we use
>are not part of that Report and Order.
>
>This was the (infamous, to some) Report and Order from the FCC that removed
>Wireless microphones off of frequencies that the FCC wants to use for
>broadband. Many organizations (particularly church groups) were left with
>suddenly illegal wireless microphones.
>
>To relate this to my MSP430 project: I will be using the MSP430 to generate
>a signal in the 160-190 KHz range. A timer will also key the signal on and
>off as Morse code. The toggled output pin will connect to a Class-D
>amplifier with 1 Watt of input. When coupled into a 50 foot antenna (maximum
>legal size) this will generate about 1 milliwatt of effective radiated
>power. Is is pure carrier.
>
>Mike

The carrier is at 160-190kHz??

Jon
Start a New Thread

>> The carrier is at 160-190kHz??

In that range, yes.

Typically, I transmit on 185.302 KHz but we can go anywhere in that range
with the equipment and power levels I have described.

Mike

On Thu, Jan 13, 2011 at 4:24 PM, Jon Kirwan wrote:

> On Thu, 13 Jan 2011 15:01:19 -0500, Mike wrote:
>
> >>> Appendix E, starting page 91, for "Wireless Audio Devices?"
> >
> >Thanks, Jon.
> >
> >Fortunately, we do not send audio (generally). And The frequencies we use
> >are not part of that Report and Order.
> >
> >This was the (infamous, to some) Report and Order from the FCC that
> removed
> >Wireless microphones off of frequencies that the FCC wants to use for
> >broadband. Many organizations (particularly church groups) were left with
> >suddenly illegal wireless microphones.
> >
> >To relate this to my MSP430 project: I will be using the MSP430 to
> generate
> >a signal in the 160-190 KHz range. A timer will also key the signal on and
> >off as Morse code. The toggled output pin will connect to a Class-D
> >amplifier with 1 Watt of input. When coupled into a 50 foot antenna
> (maximum
> >legal size) this will generate about 1 milliwatt of effective radiated
> >power. Is is pure carrier.
> >
> >Mike
>
> The carrier is at 160-190kHz??
>
> Jon
>
>


Start a New Thread

On Thu, 13 Jan 2011 17:54:39 -0500, Mike wrote:

>>> The carrier is at 160-190kHz??
>
>In that range, yes.
>
>Typically, I transmit on 185.302 KHz but we can go anywhere in that range
>with the equipment and power levels I have described.

So that helps explain why 1 watt input delivers 1/1000th of
that radiated? The antenna length of 50' is no where close
to a quarter-wave or more.

(I'm imagining a simple, straight wire type and radiation
patterns for horizontally aligned vs earth as well as
vertically aligned vs earth here. I have zero training,
experience in RF, just bits and pieces in my memory which I
poorly fathom. But at this frequency, it seems to wreck all
my recollections about far field and near field -- Fraunhofer
far field equation doesn't make any sense relative to
reactive near field equation as the one is supposed to be
larger than the other and... well, isn't.)

So now I'm interested in hearing more, I guess. I feel
pretty ignorant.

Jon
Start a New Thread

Mike,

How stable is required for that RF frequency? The on-chip DCO of MSP430 may not be stable enough (+/-3%).

You may use the 32768Hz crystal (included in the kit) as a reference to periodically adjust the DCO. I think even after that, the best you can get is about +/-0.25%. (And if you examine the clocks cycle by cycle, some of them are faster and some of them are slower -- differ by as much as 8%.)

An alternative is to wire the 12 MHz clock (available on the Launchpad board) to the target chip. The chip can divide this clock by an integer and route that to one of the pins as exciter.

--OCY

--- In m..., Mike Staines wrote:
>
> >> The carrier is at 160-190kHz??
>
> In that range, yes.
>
> Typically, I transmit on 185.302 KHz but we can go anywhere in that range
> with the equipment and power levels I have described.
>
> Mike
>
> On Thu, Jan 13, 2011 at 4:24 PM, Jon Kirwan wrote:
>
> >
> >
> > On Thu, 13 Jan 2011 15:01:19 -0500, Mike wrote:
> >
> > >>> Appendix E, starting page 91, for "Wireless Audio Devices?"
> > >
> > >Thanks, Jon.
> > >
> > >Fortunately, we do not send audio (generally). And The frequencies we use
> > >are not part of that Report and Order.
> > >
> > >This was the (infamous, to some) Report and Order from the FCC that
> > removed
> > >Wireless microphones off of frequencies that the FCC wants to use for
> > >broadband. Many organizations (particularly church groups) were left with
> > >suddenly illegal wireless microphones.
> > >
> > >To relate this to my MSP430 project: I will be using the MSP430 to
> > generate
> > >a signal in the 160-190 KHz range. A timer will also key the signal on and
> > >off as Morse code. The toggled output pin will connect to a Class-D
> > >amplifier with 1 Watt of input. When coupled into a 50 foot antenna
> > (maximum
> > >legal size) this will generate about 1 milliwatt of effective radiated
> > >power. Is is pure carrier.
> > >
> > >Mike
> >
> > The carrier is at 160-190kHz??
> >
> > Jon
> >
> >
>
>

Start a New Thread

>> So now I'm interested in hearing more, I guess. I feel
pretty ignorant.

Oh, don't. This is all experimental. Some Europeans are getting 100
Kilometers of distance sending signals at 8 KHz (in the middle of the audio
range).

If anyone else is interested you can find more information at the web page
of the Long Wave Club of America: www.lcwa.org or contact me directly at
m...@email.com

Regards,
Mike

On Thu, Jan 13, 2011 at 6:37 PM, Jon Kirwan wrote:

> On Thu, 13 Jan 2011 17:54:39 -0500, Mike wrote:
>
> >>> The carrier is at 160-190kHz??
> >
> >In that range, yes.
> >
> >Typically, I transmit on 185.302 KHz but we can go anywhere in that range
> >with the equipment and power levels I have described.
>
> So that helps explain why 1 watt input delivers 1/1000th of
> that radiated? The antenna length of 50' is no where close
> to a quarter-wave or more.
>
> (I'm imagining a simple, straight wire type and radiation
> patterns for horizontally aligned vs earth as well as
> vertically aligned vs earth here. I have zero training,
> experience in RF, just bits and pieces in my memory which I
> poorly fathom. But at this frequency, it seems to wreck all
> my recollections about far field and near field -- Fraunhofer
> far field equation doesn't make any sense relative to
> reactive near field equation as the one is supposed to be
> larger than the other and... well, isn't.)
>
> So now I'm interested in hearing more, I guess. I feel
> pretty ignorant.
>
> Jon
>
>


Start a New Thread

OCY:
Thanks for your input.

You are correct in that tight frequency control is required to really get
the super-far distances I have been refering to. Many folks have
transmitters that are GPS tempered.

For my second stab at an MSP430 program I will just use the uP as a signal
generator and make sure that I can interface it with the amplifier and
antenna I already have. The experimenters in New England should be able to
hear me using headphones.

The next step would be to use the MSP430 to control a Phase Locked Loop for
better stability.

Regards,
Mike

On Thu, Jan 13, 2011 at 7:02 PM, old_cow_yellow wrote:

> Mike,
>
> How stable is required for that RF frequency? The on-chip DCO of MSP430 may
> not be stable enough (+/-3%).
>
> You may use the 32768Hz crystal (included in the kit) as a reference to
> periodically adjust the DCO. I think even after that, the best you can get
> is about +/-0.25%. (And if you examine the clocks cycle by cycle, some of
> them are faster and some of them are slower -- differ by as much as 8%.)
>
> An alternative is to wire the 12 MHz clock (available on the Launchpad
> board) to the target chip. The chip can divide this clock by an integer and
> route that to one of the pins as exciter.
>
> --OCY
>
> --- In m... , Mike Staines
> wrote:
> >
> > >> The carrier is at 160-190kHz??
> >
> > In that range, yes.
> >
> > Typically, I transmit on 185.302 KHz but we can go anywhere in that range
> > with the equipment and power levels I have described.
> >
> > Mike
> >
> > On Thu, Jan 13, 2011 at 4:24 PM, Jon Kirwan wrote:
> >
> > >
> > >
> > > On Thu, 13 Jan 2011 15:01:19 -0500, Mike wrote:
> > >
> > > >>> Appendix E, starting page 91, for "Wireless Audio Devices?"
> > > >
> > > >Thanks, Jon.
> > > >
> > > >Fortunately, we do not send audio (generally). And The frequencies we
> use
> > > >are not part of that Report and Order.
> > > >
> > > >This was the (infamous, to some) Report and Order from the FCC that
> > > removed
> > > >Wireless microphones off of frequencies that the FCC wants to use for
> > > >broadband. Many organizations (particularly church groups) were left
> with
> > > >suddenly illegal wireless microphones.
> > > >
> > > >To relate this to my MSP430 project: I will be using the MSP430 to
> > > generate
> > > >a signal in the 160-190 KHz range. A timer will also key the signal on
> and
> > > >off as Morse code. The toggled output pin will connect to a Class-D
> > > >amplifier with 1 Watt of input. When coupled into a 50 foot antenna
> > > (maximum
> > > >legal size) this will generate about 1 milliwatt of effective radiated
> > > >power. Is is pure carrier.
> > > >
> > > >Mike
> > >
> > > The carrier is at 160-190kHz??
> > >
> > > Jon
> > >
> > >
> >
> >
> >
> >
>


Start a New Thread

>> Appendix E, starting page 91, for "Wireless Audio Devices?"

Thanks, Jon.

Fortunately, we do not send audio (generally). And The frequencies we use
are not part of that Report and Order.

This was the (infamous, to some) Report and Order from the FCC that removed
Wireless microphones off of frequencies that the FCC wants to use for
broadband. Many organizations (particularly church groups) were left with
suddenly illegal wireless microphones.

To relate this to my MSP430 project: I will be using the MSP430 to generate
a signal in the 160-190 KHz range. A timer will also key the signal on and
off as Morse code. The toggled output pin will connect to a Class-D
amplifier with 1 Watt of input. When coupled into a 50 foot antenna (maximum
legal size) this will generate about 1 milliwatt of effective radiated
power. Is is pure carrier.

Mike

On Thu, Jan 13, 2011 at 1:46 AM, Jon Kirwan wrote:

> On Tue, 11 Jan 2011 18:42:01 -0500, you wrote:
>
> >On Tue, Jan 11, 2011 at 12:04 PM, Hugo Brunert
> >wrote:
> >
> >> >> Depends what you expect to "SEE"
> >>
> >> The square-wave output will be used to drive a class-D RF amplifier for
> a
> >> FCC "Part 15" (i.e. License free) transmitter. Assuming I can get at
> least
> >> 160 - 190 Khz pulses from it...
>
> Appendix E, starting page 91, for "Wireless Audio Devices?"
>
> http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-10-16A1.pdf
>
> Jon
>
>


Start a New Thread