Company lists · Data refreshed September 2026

Top 17 Synchronized clock system manufacturers based in the United States

RevenueBase identified 37 synchronized clock system manufacturers headquartered in the United States as of September 2026 and tracks 718 professional contacts across them, including 174 with verified work emails. San Jose is the largest hub.

This list covers synchronized clock system manufacturers headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 18, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 18, 2026 86% judged on-target in blind review
37Companies
718Contacts tracked
174Verified emails
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The 17 largest synchronized clock system manufacturers based in the United States

Ranked by team size
Top 17 of 37 synchronized clock system manufacturers based in the United States, ranked by team size, largest first. Data refreshed Sep 18, 2026. RevenueBase Smart Search rates how each company's information relates to synchronized clock system manufacturers: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Indirect evidenceAliso Viejo, CA, United StatesHQ checked Sep 18, 20261,001-5,000177 contacts →

Indirect evidence

“Symmetricom was acquired by Microsemi Corporation in November 2013.”

Source: RevenueBase Database · checked Sep 18, 2026
2Partial evidenceLake Geneva, WI, United StatesHQ checked Sep 18, 202651-20088 contacts →

Partial evidence

“Primex is a global market leader of synchronized time, advanced monitoring and facility compliance technologies that improve operational efficiency and reduce risk for Healthcare…”

Source: RevenueBase Database · checked Sep 18, 2026
3Indirect evidenceSanta Ana, CA, United StatesHQ checked Sep 18, 202611-5039 contacts →

Indirect evidence

“Brandywine Communications is the premier supplier of GPS and time code based precision time and frequency products.”

Source: RevenueBase Database · checked Sep 18, 2026
4Partial evidenceAtlanta, GA, United StatesHQ checked Sep 18, 202651-20038 contacts →

Partial evidence

“Headquartered in Atlanta, Georgia, Lathem is one of the world's leading designers and manufacturers of products for business.”

Source: RevenueBase Database · checked Sep 18, 2026
5Indirect evidenceWixom, MI, United StatesHQ checked Sep 18, 202651-20031 contacts →

Indirect evidence

“A family company for over 100 years, National Time provides products and services that inform and protect people.”

Source: RevenueBase Database · checked Sep 18, 2026
6Strong evidenceSt. Charles, MO, United StatesHQ checked Sep 18, 202611-5022 contacts →

Strong evidence

“Masterclock designs and manufactures a variety of precise timekeeping products to keep both facilities and people synchronized.”

Source: RevenueBase Database · checked Sep 18, 2026
7Partial evidenceChelsea, MA, United StatesHQ checked Sep 18, 202611-5017 contacts →

Partial evidence

“Founded in 1897, Chelsea Clock is the oldest and one of the largest clock making companies in the United States.”

Source: RevenueBase Database · checked Sep 18, 2026
8Indirect evidenceLafayette, CO, United StatesHQ checked Sep 18, 20261-1013 contacts →

Indirect evidence

“Xairos offers secure and accurate timing through entangled photons.”

Source: RevenueBase Database · checked Sep 18, 2026
9Strong evidenceSan Jose, CA, United StatesHQ checked Sep 18, 202611-5012 contacts →

Strong evidence

“Protempis offers solutions providing precise time and synchronization, for telecommunications, communication systems, data centers, financial networks, utilities, factory…”

Source: RevenueBase Database · checked Sep 18, 2026
10Partial evidenceIndependence, MO, United StatesHQ checked Sep 18, 202611-5011 contacts →

Partial evidence

“NOVUS is a United States Original Brand Manufacturer of precision timing products, including Rubidium and GNSS locked frequency references, PTP/NTP time servers, distribution…”

Source: RevenueBase Database · checked Sep 18, 2026
11Strong evidenceMedfield, MA, United StatesHQ checked Sep 18, 202651-20010 contacts →

Strong evidence

“For over 80 years, Electric Time® has been a master in the art of handcrafted clock manufacture and design.”

Source: RevenueBase Database · checked Sep 18, 2026
12Indirect evidenceWakefield, MA, United StatesHQ checked Sep 18, 202611-508 contacts →

Indirect evidence

“Precise Time and Frequency, LLC is part of the LGL Group, along with sister company MtronPTI.”

Source: RevenueBase Database · checked Sep 18, 2026
13Partial evidenceValley Stream, NY, United StatesHQ checked Sep 18, 202611-504 contacts →

Partial evidence

“Westclox was originally established in 1884 as United Clock Company of Peru, Illinois based on a new, innovative idea by Charles Stahlberg.”

Source: RevenueBase Database · checked Sep 18, 2026
14Partial evidenceSan Jose, CA, United StatesHQ checked Sep 18, 202611-504 contacts →

Partial evidence

“Qulsar activates new applications and capabilities made possible by precisely synchronized time.”

Source: RevenueBase Database · checked Sep 18, 2026
15Strong evidenceAmherst, VA, United StatesHQ checked Sep 18, 202611-503 contacts →

Strong evidence

“Hermle North America is a clock manufacturer and importer of quality clocks based in Amherst, Virginia.”

Source: RevenueBase Database · checked Sep 18, 2026
16Partial evidenceSan Jose, CA, United StatesHQ checked Sep 18, 20261-103 contacts →

Partial evidence

“Digital Display Systems Inc.”

Source: RevenueBase Database · checked Sep 18, 2026
17Partial evidenceLoughman, FL, United StatesHQ checked Sep 18, 20261-102 contacts →

Partial evidence

“In the ever-evolving landscape of timekeeping technology, the paradigm has shifted with the emergence of Top Tech Clocks, redefining the standards for time zone precision.”

Source: RevenueBase Database · checked Sep 18, 2026

Showing 17 of 37 synchronized clock system manufacturers based in the United States

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Synchronized clock system manufacturers based in the United States at a glance

As of Sep 18, 2026
24.2%Verified-email coverage
19.4Average contacts per company
11-50Median size (employees)
8.1%Largest-city concentration · San Jose
Sep 18, 2026Page data refreshed

Companies by employee count

1-10
11
11-50
16
51-200
8
201-500
1
1,001-5,000
1

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 37 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among synchronized clock system manufacturers, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies
Companies headquartered in the United States whose own description of what they do matches “synchronized clock system manufacturers”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search
RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names synchronized clock system manufacturers), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude
Companies whose own description does not clearly place them among synchronized clock system manufacturers, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
Match quality
In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every listed company carries at least one verified work email, 174 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on September 18, 2026. Lists refresh periodically as the graph is re-checked.
Corrections
Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names synchronized clock system manufacturers, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many synchronized clock system manufacturers are there based in the United States?

RevenueBase identified 37 synchronized clock system manufacturers headquartered in the United States as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Symmetricom IS NOW Microsemi, headquartered in Aliso Viejo, tops this list with the largest team on record.

Which city has the most synchronized clock system manufacturers?

San Jose leads with 3 headquartered companies, followed by Valley Stream (2) and Wixom (2).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 174 verified decision-maker contacts tracked across these 37 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 18, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.