Time and Frequency References
 

How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?

--

Rick

Time and Frequency References
 

In article , rickman
wrote:

How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?

Rick-

Anyone who would use your frequency reference might be interested if it
is less expensive than other methods. I believe GPS-trained references
are available. I have a rubidium-controlled oscillator I bought on
E-Bay.

For routine Ham Radio use, I depend on 20 MHz WWV to periodically check
the calibration of my transceivers. By switching between CW and CW-R, I
can adjust the equipment so the CW pitch is the same for both. I am
confident that I can adjust a radio so it is within one Hz at 20 MHz.

That puts me within 0.05 parts per million, at least at the moment I
make the adjustment. I expect the equipment to drift over time and
temperature.

Most Amateur Radio Operators do not worry that much about frequency.
Some of the people I talk to on higher frequencies, drift over a few
minutes time. Nobody seems to care!

Fred
K4DII

Time and Frequency References
 

On 18/04/2016 15:39, rickman wrote:
How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?

A good frequency standard has many uses for the radio amateur. There are
many designs around many using GPS as the reference source as well as
MSF and the like.

--
Peter Crosland

Reply address is valid

Time and Frequency References
 

On 18/04/16 15:39, rickman wrote:
How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?


Anyone who wants high accuracy off air time and frequency standards
would use GPS these days. Even that is almost two decade old technology
in amateur radio usage: http://www.tapr.org/kits_tac2.html

Also note that cross-posting to a moderated newsgroup will delay the
posting in the unmoderated group and cross-posting to two moderated
groups will, almost certainly, stop it being distributed at all.

Time and Frequency References
 

In article ,
says...



Anyone who would use your frequency reference might be interested if it
is less expensive than other methods. I believe GPS-trained references
are available. I have a rubidium-controlled oscillator I bought on
E-Bay.

For routine Ham Radio use, I depend on 20 MHz WWV to periodically check
the calibration of my transceivers. By switching between CW and CW-R, I
can adjust the equipment so the CW pitch is the same for both. I am
confident that I can adjust a radio so it is within one Hz at 20 MHz.

That puts me within 0.05 parts per million, at least at the moment I
make the adjustment. I expect the equipment to drift over time and
temperature.

Most Amateur Radio Operators do not worry that much about frequency.
Some of the people I talk to on higher frequencies, drift over a few
minutes time. Nobody seems to care!


I just got caled out 2 nights ago for being off frequency by 50 HZ on 10
meters. Was using an Icom 706IIG.

I don't worry about things like that. As long as I am in the band and
not drifting all over the place is good enough for me. I could
calibrate it using one of the service monitors I have. Not sure how far
they are off, but they count to the last cycle of WWV at 20 MHz and will
sometimes blink to 19.99 and all 9s.

Friend that I talk to about every day usually jumps around 50 to 100 Hz
on 75 meters with a Collins and an old Yeasu.
I don't worry about that, just rit him in.

I think a low cost GPS or one of the Atomic standards would be the way
to go if the price could be low enough.

Time and Frequency References
 

On 4/18/2016 5:43 PM, David Woolley wrote:
On 18/04/16 15:39, rickman wrote:
How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?


Anyone who wants high accuracy off air time and frequency standards
would use GPS these days. Even that is almost two decade old technology
in amateur radio usage: http://www.tapr.org/kits_tac2.html

Is there something about GPS that is inherently superior for a frequency
reference? For setting a time, GPS can provide a smaller offset, but I
don't see where it has any advantages over WWVB or similar station
broadcasts where you can receive them.

The main limitation of a GPS receiver is the need for an outside antenna
for many installations. A WWVB receiver is self contained and much
lower cost.

--

Rick

Time and Frequency References
 

In article rickman writes:
On 4/18/2016 5:43 PM, David Woolley wrote:
On 18/04/16 15:39, rickman wrote:
How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?


Anyone who wants high accuracy off air time and frequency standards
would use GPS these days. Even that is almost two decade old technology
in amateur radio usage: http://www.tapr.org/kits_tac2.html

Is there something about GPS that is inherently superior for a frequency
reference? For setting a time, GPS can provide a smaller offset, but I
don't see where it has any advantages over WWVB or similar station
broadcasts where you can receive them.

The main limitation of a GPS receiver is the need for an outside antenna
for many installations. A WWVB receiver is self contained and much
lower cost.

GPS allows accurate locking to frequency, WWVB no longer does,
since they use phase modulation on the WWVB signal. The "low
cost" WWVB receivers never could do that, they are only able to
be used for clock setting, not accurate frequency determination.

The WWVB signals are much more affected by the ionosphere,
as daytime absorbtion can make the signal unusable to small
receve antennas.

Also, WWVB does need an antenna for good performance, especially
compared to small indoor antennas.

WWVB suffers from occasional interference on the east coast from MSF.

Alan

Time and Frequency References
 

rickman wrote:
On 4/18/2016 5:43 PM, David Woolley wrote:
On 18/04/16 15:39, rickman wrote:
How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?


Anyone who wants high accuracy off air time and frequency standards
would use GPS these days. Even that is almost two decade old technology
in amateur radio usage: http://www.tapr.org/kits_tac2.html

Is there something about GPS that is inherently superior for a frequency
reference? For setting a time, GPS can provide a smaller offset, but I
don't see where it has any advantages over WWVB or similar station
broadcasts where you can receive them.

The direct-sight UHF radio link provides less jitter and uncertainty
than the VLF signal that suffers from propagation effects.

The main limitation of a GPS receiver is the need for an outside antenna
for many installations. A WWVB receiver is self contained and much
lower cost.

Sure it can be easier to place an antenna for a VLF station, but on
the other hand there is much more interference, mainly from switchmode
powersupplies these days (in the old days it was from CRT computer
monitors), but also from lightning.

Time and Frequency References
 

On 4/20/2016 12:01 PM, wrote:
In article rickman writes:
On 4/18/2016 5:43 PM, David Woolley wrote:
On 18/04/16 15:39, rickman wrote:
How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?


Anyone who wants high accuracy off air time and frequency standards
would use GPS these days. Even that is almost two decade old technology
in amateur radio usage: http://www.tapr.org/kits_tac2.html

Is there something about GPS that is inherently superior for a frequency
reference? For setting a time, GPS can provide a smaller offset, but I
don't see where it has any advantages over WWVB or similar station
broadcasts where you can receive them.

The main limitation of a GPS receiver is the need for an outside antenna
for many installations. A WWVB receiver is self contained and much
lower cost.

GPS allows accurate locking to frequency, WWVB no longer does,
since they use phase modulation on the WWVB signal. The "low
cost" WWVB receivers never could do that, they are only able to
be used for clock setting, not accurate frequency determination.

The present WWVB signal still allows phase locking, just not by a
simplistic algorithm.


The WWVB signals are much more affected by the ionosphere,
as daytime absorbtion can make the signal unusable to small
receve antennas.

Also, WWVB does need an antenna for good performance, especially
compared to small indoor antennas.

Every receiver needs an antenna. But the LF time signals are easily
received inside buildings without an external antenna while the GPS
signals are readily blocked by walls and roofs. There are even problems
receiving the GPS signals accurately based on geography and local terrain.


WWVB suffers from occasional interference on the east coast from MSF.

I think "occasional" is the right word, if that. From here it is 1460
miles to WWVB transmitting at 50 kW ERP (I'm near Washington, DC) and
3,462 to MSF in Anthorn transmitting 15 kW. The directions are not far
from orthogonal (120°). A loop stick antenna at my location would
receive more noise than signal from one when receiving the signal from
the other if the signal from Anthorn can be received at all.

--

Rick

Time and Frequency References
 

On 4/20/2016 12:01 PM, Rob wrote:
rickman wrote:
On 4/18/2016 5:43 PM, David Woolley wrote:
On 18/04/16 15:39, rickman wrote:
How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?


Anyone who wants high accuracy off air time and frequency standards
would use GPS these days. Even that is almost two decade old technology
in amateur radio usage: http://www.tapr.org/kits_tac2.html

Is there something about GPS that is inherently superior for a frequency
reference? For setting a time, GPS can provide a smaller offset, but I
don't see where it has any advantages over WWVB or similar station
broadcasts where you can receive them.

The direct-sight UHF radio link provides less jitter and uncertainty
than the VLF signal that suffers from propagation effects.

That is important if you are looking for microsecond timing. But it has
very little impact on use as a frequency reference.


The main limitation of a GPS receiver is the need for an outside antenna
for many installations. A WWVB receiver is self contained and much
lower cost.

Sure it can be easier to place an antenna for a VLF station, but on
the other hand there is much more interference, mainly from switchmode
powersupplies these days (in the old days it was from CRT computer
monitors), but also from lightning.

I guess you aren't familiar with the extremely narrow band timing
signals, 1 bps. I'm working on a receiver with a 30 Hz bandwidth to
exclude environmental noise.

--

Rick