Printed Circuit Design & Fab Circuits Assembly August 2021 Cover
August 2021
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August 2021 • VOL. 38 • NO. 8
Printed Circuit Design and Fab Circuits Assembly logo
First Person
Google gets in the game.
Mike Buetow
money matters
Hard questions for software.
Peter Bigelow
Back inside.
Susan Mucha
Tech Talk
Make the BoM the bomb.
John Burkhert
Conduction avenues for non-power signals.
Terry Jernberg
How cryptocurrency mining is affecting the PCB industry.
Alun Morgan
It’s getting thick in here.
Mark Finstad
Vacuum doesn’t suck.
Clive Ashmore
No filling.
Bob Willis
August 2021 • VOL. 38 • NO. 8
Printed Circuit Design and Fab Circuits Assembly logo
If the 128 fabricators with annual sales over $100 million are segmented, the top 25 saw the largest aggregate percentage growth last year and have an almost 60% share of the cohort. And the gap is widening.
by Dr. Hayao Nakahara
Printed Circuit Design & Fab Circuits Assembly August 2021 cover
High-Speed Design
Plenty of articles over the years have discussed managing impedance and crosstalk. Others still have discussed managing loss through dielectric material selection and copper roughness, one of the two components of conductor loss. The other contributor to conductor loss is commonly known as skin effect. The physics of skin effect are hard to overcome, but there are ways to fine-tune the impedance and resistive loss.
by Bill Hargin
IN the Digital Edition
The latest Printed Circuit Engineering Association news.
The Rochester Institute of Technology Capstone Project Team
with Mike Buetow
The PCB/MCM Software Market
with Wally Rhines
Solving for Power Integrity
with Terry Jernberg
Additive Manufacturing
with Amit Dror
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Akber Roy, Peter Bigelow, John Burkhert, Mark Finstad, Bill Hargin, Nick Koop, Greg Papandrew

Clive Ashmore, David Bernard, Robert Boguski, John D. Borneman, Joseph Fama, Susan Mucha, Chrys Shea, Jan Vardaman, Ranko Vujosevic


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Caveat Lector
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Googling Your Boards

f the market is big enough, sooner or later Google will join it.

That much was laid bare in late June when the search giant cum OEM announced its latest venture, Visual Inspection AI, a new “purpose-built solution” designed to help businesses, including manufacturers, reduce defects and cut operational costs.

Now before you start doubting Google’s temerity to dive into technology that cuts across almost every industry imaginable, remember we’ve been here before.

While the company today still counts on its hugely successful targeted search marketing program for the bulk of its revenue and profits, several other businesses it has launched have made serious inroads in their respective markets. These include broadband; telecommunications; autonomous vehicles; and human health gambits (marketed under the Verily Life Sciences name). Acquisitions brought it Nest Labs, the maker of smart thermostats. Less front and center, but just as integral, are Google’s vast data centers, also known as server farms, which power its reach into just about every precipice known to man.

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Around the World
PCDF People
David Torp Headshot
Additive Circuits Technologies appointed David Torp CEO, effective Jul. 1. He has held engineering positions at Rockwell Collins and UL, and management positions at Litton, Northrop Grumman and Kester-ITW. He served six years as site director of EMD Electronics and seven years as VP of standards and technology at IPC.
Altix appointed Maximilian Mohr DACH regional sales director.

Apple promoted Jonah Stephenson to PCB manager Audio/Home/AppleTV.

Ken Parent Headshot
Insulectro promoted Ken Parent to COO, a new position, Jason Shuppert to VP of operations, and Felix Martinez to national director of operations. Vice president of operations Jeff Mason will retire in February.
Nano Dimension hired Sean Patterson as president of Nano Dimension – Americas. He previously held leadership roles at Amazon and TTM Technologies.

TopLine named Dr. Jeffrey Sokol to its advisory team to provide guidance in aerospace and defense. He is a senior engineering specialist in hybrid microcircuits, radiation effects, and system survivability.

Around the World
MKS Instruments to Buy Atotech for Over $5B

ANDOVER, MA – MKS Instruments will buy Atotech for $5.1 billion, the firm announced on Jul. 1.

The cash-and-stock deal includes $16.20 in cash and 0.0552 of an MKS common stock for each Atotech share, a per share value of around $26. The offer represents a premium of about 10% to Atotech’s closing price on Jun. 10.

Carlyle Group, which owns 79% of Atotech, has agreed to the deal.

The deal is expected to close by the fourth quarter of 2021, expanding MKS’ chip manufacturing capabilities with the addition of Atotech’s plating chemicals. (CD)

Around the World
New Book Helps Lower Risk of Compliance Test Failures
Book cover of Workbench Troubleshooting EMC Emissions (Volume 2) by Ken Wyatt
WOODLAND PARK, CO – The latest book in a series on diagnosing and troubleshooting EMC emissions written by a veteran of the electronics design industry is now available.

Ken Wyatt’s latest opus, Workbench Troubleshooting EMC Emissions (Volume 2): Simple Techniques for Radiated and Conducted Emissions Troubleshooting and Pre-Compliance Testing (EMC Troubleshooting Series), is a 239-page treatise on simple tests using the tools and accessories described earlier in the series to characterize and perform workbench-level pre-compliance tests for radiated and conducted emissions.

The book is the second in a three-volume set on EMC troubleshooting. Volume 1 includes examples of recommended measurement tools and probes useful for troubleshooting a myriad of EMC issues on a workbench or in-house. Volume 3 will include a deeper look at the top EMC immunity issues like ESD, radiated immunity and EFT.

The books sell for $20 to $40 each and are available on Amazon. (MB)

Around the World
New Product Introduction Awards Open for Entries
ATLANTA – UP Media Group has opened its 2022 New Product Introduction Awards (NPI) for printed circuit board fabrication and printed circuit board assembly.

The NPI Awards recognize the leading new products for design, fabrication and assembly introduced in the 2021 calendar year. Awards are selected by an independent panel of judges from the industry and presented by CIRCUITS ASSEMBLY. No preferential treatment is given to customers of PCD&F, CIRCUITS ASSEMBLY or UPMG.

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Online courses and webinars for the printed circuit engineering community.
Around the World
CA People
Tatsunori Muroya Headshot
Saki appointed Tatsunori Muroya chief sales officer, responsible for sales and customer relations. He has a degree in robotics from Tokyo Institute of Technology and extensive international business and management experience in over 50 countries at Mitsui.
Cicor CFO Patric Schoch left at the end of June.
ViscoTec named Franz Kamhuber managing director, replacing Georg Senftl, who retired.
CA Briefs
A*STAR’s Institute of Microelectronics (IME) announced a collaboration with four leading industry players to form a System-in-Package (SiP) consortium.

Aegis Software expanded its reseller relationship with Europlacer to include China.

Apple and Intel will be the first adopters of Taiwan Semiconductor Manufacturing’s 3nm chip technology ahead of its deployment, possibly next year.

Bharat Dynamics Ltd. (BDL) is upgrading its facility in New Delhi, India, with surface-mount technology lines.

Around the World
Neways Spurns VDL, Opts for PE Firm
EINDHOVEN, NETHERLANDS – Neways has reached a conditional agreement to sell all shares in the EMS company to private equity group Infestos for approximately €177.5 million ($209.8 million). The offer represents a premium of 34% over the closing price of the EMS firm on Apr. 29.

The offer topped that of VDL, which previously offered about €159 million for the company. Neways’ management board and supervisory board is recommending shareholders accept Infestos’ bid.

Around the World
ACDi Acquires Enhanced Manufacturing Solutions
FREDERICK, MD – ACDi in July announced the acquisition of Enhanced Manufacturing Solutions to expand its geographical footprint, increase manufacturing capacity and complement service and product offerings. No financial terms were disclosed.

ACDi will offer printed circuit board layout and electronics manufacturing services in the New England area.

“We are looking forward to welcoming Enhanced Manufacturing Solutions’ employees and clients to the ACDi family,” said Bill Hornbaker, president and CEO, ACDi. “As a company we will be ideally positioned to penetrate new industries and expand into the northeastern region of the US. We are excited to add Enhanced Manufacturing Solutions, a team that shares our vision of being an agile partner with consistent high quality and customer service.”

Around the World
India Electronics Assn Head Calls for Renewed Investment

NEW DELHI, INDIA – The US isn’t the only nation placing intense emphasis on its boosting domestic semiconductor industry. India’s primary electronics association said the country must immediately start investing in semiconductor manufacturing if it plans to become a hub for electronics.

Electronic Industries Association of India director general Rajoo Goel calls electronics manufacturing “critical to Atmanirbhar (self-reliant) India.” He pinpointed semiconductors and displays as critical components to ensure the domestic industry is competitive with China and other regions.

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Around the World
IMCO Acquires EMT Electronics Manufacturing Technologies
PERRYSBURG, OH – IMCO Group in July acquired EMT Electronics Manufacturing Technologies for up to NIS 7 million (US$2.14 million). NIS 4 million will be paid at closing, with an additional NIS 3 million subject to future profit.

“This expansion gives further in-house capabilities of designing and assembling electronic PCBs,” said Eitan Zait, CEO, IMCO. “This move is a further step in IMCO Group’s path to provide its customers with complete solutions tailored for customers’ requirements, converging toward Tier-1 customers worldwide.”

“We are proud and excited to join the IMCO Group, and are confident our proven excellence for the production and integration of electronic systems and assembly of electronic PCBs will enable the group to enrich its capabilities and provide its customers with state-of-the-art solutions at the highest standards and technologies,” said Yaniv Hadar, CEO, EMT. (CD)

Market Watch
Covid Rebound

Trends in the U.S. electronics equipment market (shipments only)

Computers and electronics products
Storage devices
Other peripheral equipment
Nondefense communications equipment
Defense communications equipment
A/V equipment
Nondefense search and navigation equipment
Defense search and navigation equipment
Medical, measurement and control
rRevised. *Preliminary. 1Includes semiconductors. Seasonally adjusted.
Source: U.S. Department of Commerce Census Bureau, July 2, 2021
Around the World
PCB ECAD Sales Continue Growth Streak
MILPITAS, CA – Printed circuit board and multichip module design software revenue increased 15.3% to $289.2 million compared to the first quarter of 2020, said the ESD Alliance in July, continuing a long run of growth. The four-quarter moving average, which compares the most recent four quarters to the prior four, increased 5.3%.

Electronic system design industry revenue increased 17% year-over-year to $3.16 billion in the first quarter, the strongest first-quarter growth ever. The four-quarter moving average rose 15%, the highest annual growth since 2011.

Around the World
Dooson to Focus on Laminate Sales for Future Growth

SEOUL – Doosan Group is selling off non-core businesses to focus on its electronics unit, according to reports.

The conglomerate’s printed circuit materials business projects 2021 operating profits will rise 17% from a year ago to 114.6 billion won ($99.9 million) on higher demand. It reported sales of 816.1 billion won last year.

Doosan forecasts electronics unit sales will rise to 2 trillion won by 2025, about 1.15 trillion won from laminates and 950 billion won in sales from new growth from displays, electric vehicle (EV) components and energy materials.

As part of a debt reduction plan, Doosan has sold its industrial and construction equipment units, which were responsible for a combined 44% of its operating profits, leaving the electronics, retail and hydrogen businesses.

Electronics now brings in 69% of the company’s overall operating profit, up from 39% before the divestitures. (MB)

New Tech Needs Standard Solutions
The trend toward keeping ideas under wraps may slow adoption.
Early in my career cutting-edge technology was personified in hardware, such as a wire EDM machine for cutting metal used in dies for wire-to-wire terminals: for instance, forks, rings and spades. No one in those days associated software with technology. It was simply some magic the IT department created to generate reports.

Decades later, most people immediately think of software, firmware and apps as technology, while the devices themselves, regardless of how advanced, are more or less just hosts for the apps. In our industry, there is far more recognition of the technology that goes into hardware and an appreciation that the two are codependent to provide the desired end-application. In fact, many in our industry may well believe the real magic is in hardware that can withstand a variety of operating environments, while providing a stable and robust platform for software to operate.

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Changing Attitudes in the Post-Covid World
It’s time to consider more in-person visits.
Are we in the post-Covid world yet? That simple question will ignite both outrage and debate in many parts of the world. Yet in other places people are ripping off their masks and starting to resume normal life. This disconnect has significant implications for electronics manufacturing services (EMS) companies and their marketing strategies. It also has implications for people not wishing to transition from temporary work-at-home settings.

I live in Texas, and our governor has made mask mandates illegal, so I have had a preview of the psychological changes that hit when people who have been masking up and hunkering down for over a year suddenly don’t have to do that anymore. I’m fully vaccinated and am choosing not to wear a mask. Once the mask mandate was lifted, stores switched to encouraging those not vaccinated to continue to wear masks, but that choice is left to patrons. The first week I went shopping without a mask, I was in the minority. Three weeks later, the aisles are full of maskless people. Even store employees are ripping off their masks. In short, attitudes on masking shift quickly once unmasking starts and case numbers continue to drop.

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designer’s notebook
Is it Time to Design Printed Circuit Boards around the Bill of Materials?
Make every chip a layout unto itself.
Being a printed circuit board designer is not easy. Parts we used to take for granted have become really hard to come by. Geopolitical trade wars and a pandemic were serious triggers for the undersupply. We really didn’t need a Japanese chip factory to burn down to make things worse. A giant cargo hauler clogging up a vital shipping artery for a week was no help either.

The fear, uncertainty and doubt sown into the supply chain put the squeeze on purchasing managers who, in turn, did their best to secure as much material as possible. Ordering more inventory than their forecasted requirements is a typical kneejerk reaction for the big players. Some purchase orders may be defensive measures, an effort to block competitors that are caught shorthanded themselves.

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Learning from the Quality Auditors
Those who buy and specify every day have much to teach us about the industry.
Are you finding your place in the PCB industry? Are you feeling a bit disconnected from the rest of the world as you perform your PCB engineering job? Maybe you should consider joining a trade organization. Aligning and participating with a trade org that is well matched to your areas of expertise can be a monumental benefit to your career. It can put you in touch with others who can help you discover what you don’t know, but perhaps you’ve needed to know!

Our industry has many PCB engineering development groups and trade organizations. Finding the right ones to join may not be as easy as you think. Following some of the criteria PCB engineering quality assurance stakeholders use to find good products and services for their company makes it easier to narrow the list.

Jernberg pi
Your PDN’s Other Job: Closing the Loop with the Return Path
Conduction avenues for the non-power signals.
We’ve discussed the importance and care required when routing the power delivery network (PDN) of modern printed circuit boards. From how to support current supply needs, loop inductance, and defining layer stack-ups, it may seem we’ve addressed all the power concerns one could have. This is just a fraction of the considerations a designer needs to keep in mind, however. The PDN has an important secondary role that has nothing to do with power delivery. Often forgotten, the PDN is responsible for roughly 50% of the conduction avenues for the non-power signals.

Commonly referred to as return path, this routing “completes the loop,” enabling current to flow. It can be as influential (and problematic) to signal quality as the transmission lines we study in detail. In fact, failure to address the return path is a leading cause of signal integrity issues. Perhaps more troubling, they frequently go undetected even in the setting of comprehensive simulation.

material gains
Cryptocurrency Mining is Energy-Intensive. Is It Also an Energy Solution?
The controversial technology could help cut the carbon footprint of daily living.
We know the pandemic has forced many to work from home (WFH) and as a result driven up demand for products like PCs and home IT equipment. There has also been a large reduction in commuting to and from workplaces, which many have enjoyed and vowed to continue even after lockdowns are lifted.

These changes ought to benefit the planet by reducing greenhouse gas emissions and other pollution. We should consider the impact of the extra demands placed on data infrastructures to handle this upsurge in remote working, however. It takes energy to move all that data back and forth, although arguably this would happen whether workers are at the office or at home.

the Flexperts
Flex Material Thickness
A little information goes a long way – but can carry added cost.
“My company has traditionally specified the finished thickness for each flex printed circuit (FPC) layer, and total thickness. This is because it’s understood some material layer thicknesses (i.e., adhesives) change during the manufacturing process due to compression and curing. As a purchaser of FPCs, we are less concerned with the initial raw material thickness than the finished thickness.

“We have received feedback, however, that the FPC market in general specifies the raw material thickness used in FPC fabrication, and not finished thickness. The assertion was nearly all customers purchasing FPCs follow this rule to minimize miscommunication. Is this common practice?”

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‘Big Gets Bigger and Faster’
The largest circuit board fabricators are pulling away from the rest of the market. by Dr. Hayao Nakahara
This is the 25th NTI-100 report. The author cannot believe he has done NTI-100 such a long time. As years go by, it becomes more difficult to accurately record revenue data of privately owned PCB fabricators, and there are many. As a result, the data of about one-fifth of the top PCB companies are questionable. Nevertheless, it is interesting to see the revenue trend.

As usual, data compiled by trade organizations and with the assistance of many of the author’s friends around the globe were vital to completing this report. He expresses his gratitude to all who helped. Any errors are strictly his responsibility.

The 2020 average exchange rate conversion of revenue from local currencies to the US dollar was made using the exchange rates listed in Table 1. Since various organizations and individuals seem to use slightly different rates, the results may differ but only slightly.

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High-speed design
Resistive Loss is Only Skin Deep
Mitigating skin effect’s impact on high-speed signals.
by Bill Hargin
I’ve spent much of the past seven years dealing with insertion loss as it relates to PCB dielectrics, as well as losses due to copper roughness. During that period, there’s been comparatively little discussion regarding “skin effect,” a significant contributor to signal attenuation that in my view gets less attention than it should. While discussing the phenomenon in-depth, we’ll also discuss what, if anything, can be done to mitigate its impact on high-speed signals.

While writing this article, I’ve been thinking of places that skin appears in nature and pop culture. When I started writing, I flipped on Skinwalker Ranch on the History Channel for the first time as background noise, and they were talking about magnetic fields, current flow, and Tesla coils.

Great designs
require more than
good tools.
You also have to know how to use them.
Box of tools used for circuit engineering
Trades from: Rick Hartley, Susy Webb, Lee Ritchey, Dan Beeker, Eric Bogatin, Mike Creeden, Gary Ferrari, and more! text
Online courses and webinars for the printed circuit engineering community.
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SCREEN printing
A Different Take on Tooling
Reconfigurable with dedicated-like support.
AS BOARD COMPLEXITY has increased with decreasing pitches, thicknesses and component sizes, ensuring support for thin, high-density substrates – essential to cost-effective, pinpoint accuracy stencil printing – continues to pose challenges. Using vacuum to secure miniaturized assemblies is, for the most part, a successful technique but requires the use of dedicated tooling plates, which can be costly. Considering the quantities of dedicated tooling blocks needed in a high-volume manufacturing environment, finding a suitable, lower-cost alternative has been a longstanding ambition. And, while commercialized automatic pin-based tooling systems are a good option for some applications, they are not as effective for high-density, thin boards.
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Defect of the Month
It’s Reliable, But Didn’t Fill the Hole
Is the board preheat process optimized?
THIS MONTH WE look at incomplete fill of plated through-holes. During any soldering operation a balance of flux and solder/paste chemistry and soldering temperatures creates good and reliable joints. In FIGURE 1 the solder has not filled the hole completely but still exceeds the requirements of IPC-A-610, class 2 of 50%; measured, it may be 75% filled.
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Off The Shelf
off the shelf typography
Machines Materials Tools Systems Software
MegaVIA plasma treatment system
Nordson March MegaVIA
MegaVIA plasma treatment system has 15-cell configuration for panel sizes up to 30″ x 52″. Overall dimensions are 1652mm x 1782mm x 2326mm. Provides plasma treatment at 40kHz and accommodates common gases – CF4, O2, N2, and argon – with process reproducibility and uniformity. EPC controller with Windows 10 PC-based touchscreen HMI permits data collection and control capabilities. Reportedly achieves higher than 80% uniformity for desmear and etch-back applications to both sides of PCB panels.
Nordson March
PilotV8XL HR Next flying probe
Seica PilotV8XL HR Next
PilotV8XL HR Next flying probe offers probe card test. Brings together three tools to perform complete test: bare board test for single MLO and PCB test; ICT and functional test for assembled PCB test; probe card test for PCB+MLO. Ensures ICCT (integrity connection certification testing). Features vertical platform; eight independent axes; two standard probes plus two high-res probes on front side; four standard probes on rear side. Test area is 800 x 650mm. Has laser sensor(s) for warpage control. Automatically generates specific tests considering resistance of each single path that can be different from one to another.
CR-8000 2021 software
Zuken CR-8000 2021
CR-8000 2021 software features more than 150 enhancements ranging from architectural planning, system-level schematic design and verification, 3-D multi-board and advanced packing layout, through to manufacturing output generation. New place by area, template and reuse functionality that enables application of existing placement and routing patterns on new designs. Supports simulation of PCB parasitic effects in circuit design stage.
Off The Shelf
off the shelf typography
Machines Materials Tools Systems Software
YRi-V 3-D hybrid AOI
Yamaha YRi-V
YRi-V 3-D hybrid AOI features a newly developed inspection head equipped with a high-speed camera with a new 5µm resolution lens. High-precision 8-direction 3-D projector offers greater component inspection compatibility. New coaxial lighting improves measurement accuracy and range by 100% compared to current models. High-precision measurement up to 25mm high.
Yamaha SMT Section
APT-1600FD-SL dual-sided flying probe test system
Takaya APT-1600FD-SL
APT-1600FD-SL dual-sided flying probe test system is for large PCBAs for 5G communications and battery management system applications. Provides 48% larger test area. Deploys flying probes to both sides of UUT. Provides average head speed increases of up to 50% with throughput improvements of 30-50% over existing models.
rLSR Mini LED rework system
Laserssel rLSR
rLSR Mini LED rework system enables industry to solder temperature-sensitive, warpage-prone, fine-pitch, odd form, big die, SiP, wearables, flex to flex, and other applications. Beam shaping optical module takes energy of spot laser and turns it into uniformly distributed area laser. Uniformity of energy is reportedly greater than 95%.
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Technical Abstracts
In Case You Missed It
“Impact of Thermal Cycling on Cu Press-Fit Connector Pin Interconnect Mechanical Stability”

Authors: Yeon-Jin Baek, et al.

Abstract: Press-fit technology provides an electrical and mechanical connection by inserting a press-fit pin into a through-hole of a printed circuit board. Recently, there has been wide interest in the long-term reliability of the press-fit pin interconnect of electric systems under various thermo-mechanical conditions due to the integration and minimization of electric devices. Compared to a ball grid array interconnection, press-fit pin connector interconnects are expected to have a different degradation mechanism. In this study, the impact factors affecting the reliability and degradation mechanism of press-fit connector pins were investigated. The bonding strength of inserted pins was measured before and after thermal cycling at room temperature and elevated temperature conditions. The bonding strength of the press-fit pins to the PCB copper wall was observed to increase after thermal cycling. The development of an intermetallic compound between the Cu pin and the Cu wall was observed. The microstructure of the press-fit connector pin and the Cu wall and localized stress and strain levels were analyzed by electron backscattered diffraction, including inverse pole figure maps, grain reference orientation deviation maps, and strain contouring maps. Along with the increase of pull strength after thermal cycling, an increase in residual stresses was observed, while strain contouring maps exhibited a decrease in localized strains at the interface between a press-fit pin and copper wall of a PCB. (Journal of Electronic Materials, Jun. 8, 2021,

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Thanks for reading our August 2021 issue!