"Tim Shoppa" wrote in message
oups.com...
Of the longwave radio frequencies used for time standards, 40kHz (JJY,
Japan), 77.5kHz (DCF, Germany) and 60 kHz (WWVB and MSF) crystals are
off-the-shelf items in the Digikey catalog at less than a dollar each.

Really...! Hmm... perhaps time to re-visit the "WWVB receiver using op-amps
and a small microcontroller" ida? One of the regular contributors to
Circuit Cellar Ink tried it a while back (4 years?), but wasn't successful.
A successful project would be worth a write-up in some hobbyist magazine (of
what's left... Nuts & Volts seems to be about it in the US...)

Anyone know which time service folks in Oz or the Kiwis use?

---Joel Kolstad

Joel Kolstad wrote:

Really...! Hmm... perhaps time to re-visit the "WWVB receiver using op-amps
and a small microcontroller" ida? One of the regular contributors to
Circuit Cellar Ink tried it a while back (4 years?), but wasn't successful.
A successful project would be worth a write-up in some hobbyist magazine (of
what's left... Nuts & Volts seems to be about it in the US...)

---Joel Kolstad


Take a look at Jim Thompson's early design. He's an IC designer who
hangs out on the sci.electronics.* newsgroups.
http://www.analog-innovations.com/SE...matic+Data.pdf

--
Former professional electron wrangler.

Michael A. Terrell
Central Florida

"Michael A. Terrell" wrote in message
...
Take a look at Jim Thompson's early design. He's an IC designer who
hangs out on the sci.electronics.* newsgroups.

Yes, I've seen Jim's design before; it's quite impressive for 1974! For a
contemporary design, the idea is that you could get by with far fewer parts
(if not fewer transistors -- they're just buried in the ICs!).

---Joel

On Tue, 5 Apr 2005 11:57:38 -0700, "Joel Kolstad"
wrote:

"Michael A. Terrell" wrote in message
...
Take a look at Jim Thompson's early design. He's an IC designer who
hangs out on the sci.electronics.* newsgroups.

Yes, I've seen Jim's design before; it's quite impressive for 1974! For a
contemporary design, the idea is that you could get by with far fewer parts
(if not fewer transistors -- they're just buried in the ICs!).

---Joel


Particularly considering it was done BC (Before CAD :)

Maybe I should try it again, using off-the-shelf components ??

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Jim Thompson wrote:

On Tue, 5 Apr 2005 11:57:38 -0700, "Joel Kolstad"
wrote:

"Michael A. Terrell" wrote in message
...
Take a look at Jim Thompson's early design. He's an IC designer who
hangs out on the sci.electronics.* newsgroups.

Yes, I've seen Jim's design before; it's quite impressive for 1974! For a
contemporary design, the idea is that you could get by with far fewer parts
(if not fewer transistors -- they're just buried in the ICs!).

---Joel


Particularly considering it was done BC (Before CAD :)

Maybe I should try it again, using off-the-shelf components ??

...Jim Thompson


A "Before and after"?

--
Former professional electron wrangler.

Michael A. Terrell
Central Florida

Hello Jim,

Particularly considering it was done BC (Before CAD :)

Maybe I should try it again, using off-the-shelf components ??

To be fair you'd have to do it with components that were available at
reasonable prices in that era. My 2nd DCF receiver was built with
several AF126 germanium transistors. On the first one I cheated by using
opamps and somehow that didn't feel right back then.

Except for the fact that one receiver drove a Nixie display I never
built one with tubes. Now wouldn't that be something?

Regards, Joerg

http://www.analogconsultants.com

Hello Tim,

Of the longwave radio frequencies used for time standards, 40kHz (JJY,
Japan), 77.5kHz (DCF, Germany) and 60 kHz (WWVB and MSF) crystals are
off-the-shelf items in the Digikey catalog at less than a dollar each.
I'm guessing their easy availability is because they are commonly used
in real receivers.

Yes, but if these crystals are the only thing you'd have to buy right
now that would easily become $10 with S&H. Or about half of what an
atomic clock is at the discounters and there the price includes a huge
display along with the receiver parts.

I've always noted with some curiosity that 77.503kHz, 60.002kHz, and
60.005kHz are off-the-shelf crystals too... used in a direct conversion
receiver for DCF/WWV to 3Hz, 2Hz, and 5Hz carrier-detect frequencies
maybe?

Strange. Maybe another resonance mode?

Regards, Joerg

http://www.analogconsultants.com

Joerg wrote:

I've always noted with some curiosity that 77.503kHz, 60.002kHz, and
60.005kHz are off-the-shelf crystals too... used in a direct conversion
receiver for DCF/WWV to 3Hz, 2Hz, and 5Hz carrier-detect frequencies
maybe?

Strange. Maybe another resonance mode?

Regards, Joerg


Maybe use them with the 60.000 KHz crystals to build a very narrow
crystal filter?

--
Former professional electron wrangler.

Michael A. Terrell
Central Florida

Hello Michael,

Maybe use them with the 60.000 KHz crystals to build a very narrow
crystal filter?

Maybe but most WWVB receivers are more crude. They aren't concerned
about shape factors and stuff, all they want is enough selectivity to
make sure the things sync at night even if in California or Arizona. So
there is usally one crystal as a filter, or two in series for the better
ones.

Regards, Joerg

http://www.analogconsultants.com

On Tue, 05 Apr 2005 21:56:31 +0000, Joerg wrote:

Hello Jim,

Particularly considering it was done BC (Before CAD :)

Maybe I should try it again, using off-the-shelf components ??

To be fair you'd have to do it with components that were available at
reasonable prices in that era. My 2nd DCF receiver was built with several
AF126 germanium transistors. On the first one I cheated by using opamps
and somehow that didn't feel right back then.

Except for the fact that one receiver drove a Nixie display I never built
one with tubes. Now wouldn't that be something?

Yabbut, it'd be a little cumbersome for a wall clock. ;-)

Cheers!
Rich