• Important Executive Director Announcement from the NAWCC

    The NAWCC Board of Directors is pleased to announce that Mr. Rory McEvoy has been named Executive Director of the NAWCC. Rory is an internationally renowned horological scholar and comes to the NAWCC with strong credentials that solidly align with our education, fundraising, and membership growth objectives. He has a postgraduate degree in the conservation and restoration of antique clocks from West Dean College, and throughout his career, he has had the opportunity to handle some of the world’s most important horological artifacts, including longitude timekeepers by Harrison, Kendall, and Mudge.

    Rory formerly worked as Curator of Horology at the Royal Observatory, Greenwich, where his role included day-to-day management of research and digitization projects, writing, public speaking, conservation, convening conferences, exhibition work, and development of acquisition/disposal and collection care policies. In addition, he has worked as a horological specialist at Bonhams in London, where he cataloged and handled many rare timepieces and built important relationships with collectors, buyers, and sellers. Most recently, Rory has used his talents to share his love of horology at the university level by teaching horological theory, history, and the practical repair and making of clocks and watches at Birmingham City University.

    Rory is a British citizen and currently resides in the UK. Pre-COVID-19, Rory and his wife, Kaai, visited HQ in Columbia, Pennsylvania, where they met with staff, spent time in the Museum and Library & Research Center, and toured the area. Rory and Kaai will be relocating to the area as soon as the immigration challenges and travel restrictions due to COVID-19 permit.

    Some of you may already be familiar with Rory as he is also a well-known author and lecturer. His recent publications include the book Harrison Decoded: Towards a Perfect Pendulum Clock, which he edited with Jonathan Betts, and the article “George Graham and the Orrery” in the journal Nuncius.

    Until Rory’s relocation to the United States is complete, he will be working closely with an on-boarding team assembled by the NAWCC Board of Directors to introduce him to the opportunities and challenges before us and to ensure a smooth transition. Rory will be participating in strategic and financial planning immediately, which will allow him to hit the ground running when he arrives in Columbia

    You can read more about Rory McEvoy and this exciting announcement in the upcoming March/April issue of the Watch & Clock Bulletin.

    Please join the entire Board and staff in welcoming Rory to the NAWCC community.

IBM Need help trouble shooting a 2 wire IBM / Simplex system.


Registered User
Jul 12, 2007
Hi. I have a strange one here. I am hopping someone can help me figure this out.

Problem. 2 wire IBM / Simplex system runs one min faster then the master.
The particulars.
Slave clocks
are a variety of IBM and Simplex from 1920 to about 2000 most are IBM two coil high quality brass movement or Simplex one coil metal gears and 60 tooth wheel. There are no one min cams. (I think)
Boosters There are two boosters, one connected directly to the master, and one down stream in another wing. Both boosters are Latham PS8-24B
Master National Time and Signal MC-100
This is where it gets interesting. The master has a programing error. It's 2 wire output called Cincinnati D3 is as follows
XX:00 - XX:49 2 sec Positive pulse each minute (59 sec and 60th sec.) I know, That is wrong.
XX:50 - XX:58 2 sec Negative pulse each minute.
XX:59 One 2 sec Positive pulse followed by twenty 2 sec negative pulses.

OK, That's odd, but it seems to me, that it should work as long as the slaves are working OK but every clock in the building runs one minute fast.

More details. A lone slave connected directly to the master for testing keeps correct time.

If the other slaves in the building are stopped for two minutes, they will catch up to the correct time at the 59th minute. 12 hrs later they were still on time (I think) 2 days later they were one min fast.

They will run weeks and never gain another minute.

I want to ask the manufacture to correct the software (Firm where) in there master but it would help if I could tell them why it doesn't work.

BTW This is for our church school. It is a working system but I maintain it for free. That and the fact that it is OLD are why I am asking for help on this forum.


Thank You

PS8-24 B.jpg


Registered User
Nov 1, 2006
I'm not familiar with this, but you say the error is Cincinnati D3, I think you might look in the master instructions and see if there is an option for a Simplex 2 wire. I know that the Simplex model 2350 and 6350 had a listing in the installation instructions for competitive equipment you had to set the dip switches on the CPU I believe. Maybe the switches are set wrong.


Registered User
Jul 12, 2007
Update. I installed a home made three wire to two wire converter so now I have the correct pulses (Gets rid of the wrong 59th min pulse) The system is now on time and works as it should.

I know the 59th min pulse was wrong polarity, but I don't know why it made the system one min fast.


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