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Re: [time-nuts] RS-232 Pin Outs for the Acron Zeit WWVB LCD Clock

GB
Gregory Beat
Sat, Jul 22, 2017 4:33 PM

The LM-358 Op-Amp is used to Invert the Serial Data (RxD, TxD) stream.
http://www.st.com/content/ccc/resource/technical/document/datasheet/61/46/87/01/98/ed/44/c5/CD00000464.pdf/files/CD00000464.pdf/jcr:content/translations/en.CD00000464.pdf

Coupled with the usage of an RJ11 (4P4C, modular) ...
the connection would have to be a minimal 3-wire serial (RS-232 or TTL/UART)
https://en.m.wikipedia.org/wiki/RS-232#3-wire_and_5-wire_RS-232
Ground is easy to find, and TxD and RxD is a coin-toss (50:50) if you hook-up right.

greg, w9gb

I thought I could answer this question (Acron Zeit) easily, since I had the cable right
at hand. But my continuity detector gave strange results.

I opened up the D-shell and found a small circuit board with diode,
capacitors and what looks like an ST358 op amp.

Paul Alfille

Fri, Jul 21, 2017 at 4:27 PM, Philip Jackson <> wrote:
Does anyone have the serial pinout info for the Acron Zeit clock?

Sent from iPad Air

The LM-358 Op-Amp is used to Invert the Serial Data (RxD, TxD) stream. http://www.st.com/content/ccc/resource/technical/document/datasheet/61/46/87/01/98/ed/44/c5/CD00000464.pdf/files/CD00000464.pdf/jcr:content/translations/en.CD00000464.pdf Coupled with the usage of an RJ11 (4P4C, modular) ... the connection would have to be a minimal 3-wire serial (RS-232 or TTL/UART) https://en.m.wikipedia.org/wiki/RS-232#3-wire_and_5-wire_RS-232 Ground is easy to find, and TxD and RxD is a coin-toss (50:50) if you hook-up right. greg, w9gb === I thought I could answer this question (Acron Zeit) easily, since I had the cable right at hand. But my continuity detector gave strange results. I opened up the D-shell and found a small circuit board with diode, capacitors and what looks like an ST358 op amp. Paul Alfille == Fri, Jul 21, 2017 at 4:27 PM, Philip Jackson <> wrote: Does anyone have the serial pinout info for the Acron Zeit clock? --- Sent from iPad Air
PJ
Philip Jackson
Sat, Jul 22, 2017 7:50 PM

I'm wondering if something like this $10 item

http://www.nulsom.com/datasheet/NS-RS232_en.pdf

Would perform the same function as the components in the factory cable once I've figured the pinout at the clock end, which shouldn't be too hard unless someone has done that already.  Or would I need to find an similar device which inverts the incoming logic first?
TTL to RS-232 adapters seem fairly common and probably cheap for them just to source off the shelf from an OEM supplier.
I don't know if I've seen an inverting one and that would seem a more costly approach than handling the inversion on the clock board.
Philip

----- Original message -----
From: Gregory Beat w9gb@icloud.com
To: time-nuts@febo.com
Cc: paul.alfille@gmail.com, TimeNuts@philipjackson.com
Subject: Re: [time-nuts] RS-232 Pin Outs for the Acron Zeit WWVB LCD ClockDate: Sat, 22 Jul 2017 12:33:01 -0400

The LM-358 Op-Amp is used to Invert the Serial Data (RxD, TxD) stream.
http://www.st.com/content/ccc/resource/technical/document/datasheet/61/46/87/01/98/ed/44/c5/CD00000464.pdf/files/CD00000464.pdf/jcr:content/translations/en.CD00000464.pdf
Coupled with the usage of an RJ11 (4P4C, modular) ...
the connection would have to be a minimal 3-wire serial (RS-232 or TTL/UART)https://en.m.wikipedia.org/wiki/RS-232#3-wire_and_5-wire_RS-232
Ground is easy to find, and TxD and RxD is a coin-toss (50:50) if you hook-up right.
greg, w9gb

I thought I could answer this question (Acron Zeit) easily, since I had the cable right
at hand. But my continuity detector gave strange results.

I opened up the D-shell and found a small circuit board with diode,
capacitors and what looks like an ST358 op amp.

Paul Alfille
==Fri, Jul 21, 2017 at 4:27 PM, Philip Jackson <> wrote:
Does anyone have the serial pinout info for the Acron Zeit clock?

Sent from iPad Air

I'm wondering if something like this $10 item http://www.nulsom.com/datasheet/NS-RS232_en.pdf Would perform the same function as the components in the factory cable once I've figured the pinout at the clock end, which shouldn't be too hard unless someone has done that already. Or would I need to find an similar device which inverts the incoming logic first? TTL to RS-232 adapters seem fairly common and probably cheap for them just to source off the shelf from an OEM supplier. I don't know if I've seen an inverting one and that would seem a more costly approach than handling the inversion on the clock board. Philip ----- Original message ----- From: Gregory Beat <w9gb@icloud.com> To: time-nuts@febo.com Cc: paul.alfille@gmail.com, TimeNuts@philipjackson.com Subject: Re: [time-nuts] RS-232 Pin Outs for the Acron Zeit WWVB LCD ClockDate: Sat, 22 Jul 2017 12:33:01 -0400 The LM-358 Op-Amp is used to Invert the Serial Data (RxD, TxD) stream. http://www.st.com/content/ccc/resource/technical/document/datasheet/61/46/87/01/98/ed/44/c5/CD00000464.pdf/files/CD00000464.pdf/jcr:content/translations/en.CD00000464.pdf Coupled with the usage of an RJ11 (4P4C, modular) ... the connection would have to be a minimal 3-wire serial (RS-232 or TTL/UART)https://en.m.wikipedia.org/wiki/RS-232#3-wire_and_5-wire_RS-232 Ground is easy to find, and TxD and RxD is a coin-toss (50:50) if you hook-up right. greg, w9gb === I thought I could answer this question (Acron Zeit) easily, since I had the cable right at hand. But my continuity detector gave strange results. I opened up the D-shell and found a small circuit board with diode, capacitors and what looks like an ST358 op amp. Paul Alfille ==Fri, Jul 21, 2017 at 4:27 PM, Philip Jackson <> wrote: Does anyone have the serial pinout info for the Acron Zeit clock? --- Sent from iPad Air
TV
Tom Van Baak
Sat, Jul 22, 2017 8:48 PM

Or would I need to find an similar device which inverts the incoming logic first?

It's not just inversion but also level shifting. Many battery operated devices run from a dual or even single AA battery. The custom serial adapter shipped with these units handles the conversion of 1.5 or 3.0 volt CPU serial to a more PC-friendly 0 to 5 V, or -10 to +10 V RS232 serial.

Use a 'scope on both ends of your adapter to see the actual voltages during data transfer. You want to avoid blindly using a 3.3 or 5 volt USB adapter on a 1.5 volt device.

/tvb

> Or would I need to find an similar device which inverts the incoming logic first? It's not just inversion but also level shifting. Many battery operated devices run from a dual or even single AA battery. The custom serial adapter shipped with these units handles the conversion of 1.5 or 3.0 volt CPU serial to a more PC-friendly 0 to 5 V, or -10 to +10 V RS232 serial. Use a 'scope on both ends of your adapter to see the actual voltages during data transfer. You want to avoid blindly using a 3.3 or 5 volt USB adapter on a 1.5 volt device. /tvb