I need a Temic U4224B chip, which is used for reception of DCF and
WWVB time signals at vlf.

Are these available without going to Europe?

Thanks,

A

Hello Albert,

I need a Temic U4224B chip, which is used for reception of DCF and
WWVB time signals at vlf.

Are these available without going to Europe?

I am not sure you can get them at all. It might have been obsoleted by now.

Regards, Joerg

http://www.analogconsultants.com

In article ,
Joerg wrote:
Hello Albert,

I need a Temic U4224B chip, which is used for reception of DCF and
WWVB time signals at vlf.

Are these available without going to Europe?

I am not sure you can get them at all. It might have been obsoleted by now.


In any case, Temic was bought out by Atmel.

Mark Zenier Washington State resident

Hello Mark,

In any case, Temic was bought out by Atmel.

I believe Atmel called this chip T4224 but when looking for it on their
web site it ain't there.

Regards, Joerg

http://www.analogconsultants.com

The "usual" way of getting a WWVB receiver chip is to buy a cheap WWVB
clock and rip out the chip and antenna. Some have external
chips/antenna connected via cable already.

A web page showing how to do this with a commonly available Sony WWVB
clock is at:

http://www.leapsecond.com/pages/sony-wwvb/

Tim.

Hello Tim,

The "usual" way of getting a WWVB receiver chip is to buy a cheap WWVB
clock and rip out the chip and antenna. Some have external
chips/antenna connected via cable already.

Agree. Many like the Sony even contain two crystals. These alone can
cost more than a whole clock.

But if it's a matter of pride you can build your own even without any
special chips. When I was a kid I built a receiver for DCF in Europe. No
crystals, only a few transistors and 741 opamps. It worked great, except
that I didn't have a PC or anything to decode the signal with. It was
just the detected pulses but these came through nice and clear. With
today's opamps you wouldn't even need any transistors to do it. A decent
quad can be had for 50c while I paid a whopping $3 for a single
re-labeled 741 of rather dubious quality level.

Regards, Joerg

http://www.analogconsultants.com

Thanks for this info. Unfortunately, Atmel doesn't make the T4334 now.

But, while searching the site for keywords, I found the ATA5283 and
ATA5282 125 khz receiver chips that draw less than 4 microamps while
listening. I don't think there is anything inside the chip that limits
the frequency of operation though, these should operate at much lower
frequencies if an appropriate tuned circuit is attached.

So, I will look at these chips in detail later.

I was attracted to the Temic wwvb/dcf77 receiver chips because they
draw 30 microamps...so, a receiver that draws 4 microamps is indeed
low power and is very promising.

Regards,

A


In any case, Temic was bought out by Atmel.

I believe Atmel called this chip T4224 but when looking for it on their
web site it ain't there.

Hello Albert,

I was attracted to the Temic wwvb/dcf77 receiver chips because they
draw 30 microamps...so, a receiver that draws 4 microamps is indeed
low power and is very promising.

AFAIK many "atomic clocks" listen to WWVB briefly and then turn off the
receiver again. With a very low on/off duty cycle the power consumption
of the receiver wouldn't matter so much.

Regards, Joerg

http://www.analogconsultants.com

two crystals. These alone can cost more
than a whole clock.

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.

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?

Tim.

I just noticed the availability of these crystals as I was thinking
about using a crystal in the front end to protect the receiver from
adjacent frequency qrm. Not sure if this can be done unless one has a
chip specially designed to take crystals (such as the Temic U4224B).

Regarding the off frequency crystals.... It might be possible that
these are rejects that didn't quite make the 60.000 kilohertx spec?

Thanks,

A


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.

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?