Tag Archives: What makes stuff tick?

Theory of Operation and Calibration: D.C. Johnson FAC-1

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Here is another D.C. Johnson and Associates Inc. product from 1984, the FAC-1. This is the most prolific device of it’s kind. Originally designed in 1981 by Dave Johnson to retrofit European market version cars built from 1977 to 1986 equipped with a CIS Electro-Mechanical Fuel Injection System known as K-Jetronic. Tens of thousands were manufactured and installed. Many are still in service today.

The D.C. Johnson FAC-1 is an Air/Fuel control unit. It adds the closed loop Oxygen sensor feedback loop to CIS Fuel Injection Systems not originally equipped with this feature. It was designed to retrofit cars built for sale in the European market before emissions regulations were instituted. This add on allowed them to meet United States specifications after they were imported into the United States of America.

ENGINEER”S NOTE: One of my “Hobbies” is upkeep of the legacy of this product line created by my Father, David C. Johnson. These devices were produced from 1981 through 1986. The company that manufactured and marketed them (D.C. Johnson and Associates Inc.) was founded in late 1982 and was closed in August 1986. I created the website dc-johnson.com in 2008 after an inquiry into the availability of technical information. This led to the realization that there was an ongoing interest in maintaining theses products and the cars on which they are installed.

Vernon Johnson August 5, 2014.

More about dc-johnson.com.

If you have found this video useful, please consider supporting dc-johnson.com with a donation.

1984 D.C. Johnson FAC-3

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The box you see here is a 1984 D.C. Johnson FAC-3 designed to retrofit the European market version of the 1984 and 1985 Porsche 928. These cars were equipped with a Hotwire Mass Airflow Electronic Fuel Injection System known as LH Jetronic.

The D.C. Johnson FAC-3 is an Air/Fuel control unit that adds the closed loop Oxygen sensor feedback loop to Electronic Fuel Injection Systems not originally equipped with this feature. It was designed to retrofit cars built for sale in the European market before emissions regulations were instituted, to meet United States specifications after they were imported into the United States of America.

ENGINEER”S NOTE: One of my “Hobbies” is upkeep of the legacy of this product line created by my Father David C. Johnson. These devices were produced from 1981 through 1986. The company that marketed them (D.C. Johnson and Associates Inc.) was founded in late 1982 and was closed in August 1986. I created the website dc-johnson.com in 2008 after an inquiry into the availability of technical information. This led to the realization that there was an ongoing interest in maintaining theses products and the cars on which they are installed.

Vernon Johnson May 15, 2014.

More about dc-johnson.com.

1983 D.C. Johnson FAC-1 Revision C

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This is a 1983 D.C. Johnson FAC-1 Revision C. It works like new with just few minor repairs. That’s 30 years in service and now ready for many more. Not bad!

The D.C. Johnson FAC-1 is an Air/Fuel control unit similar in function to the OEM “Lambda Controller” units for European cars equipped with mechanical fuel injection systems. It was designed to retrofit cars made for sale in the European market before emissions regulations were instituted, to meet United States specifications after they were imported into the United States of America.

Electromechanical Timer Teardown

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This basic electromechanical timer was installed in a low voltage landscape lighting transformer.  It lasted a couple months short of 10 years.  I opened it up to see and show how it was designed and why it failed.  The clock motor was still working.  The contacts got eroded enough over the years that they were no longer closing.

A good example of simple and low cost electromechanical product design.

Blackhat SEO

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There’s a reason you don’t see spam comments on this blog. It is moderated for all comments, that’s why.

I do notice after each new post is made, a flurry of irrelevant comments appear in the cue awaiting moderation. Invariably some sort of spam (automated) attempts at link farming to boost some other site’s backlink array, blah blah blah.

After a recent very sparse post, 2 such comments appeared in the cue and the backlink address in one of them caught my eye (gscraper.com) so I decided to investigate…

Black Hat SEO Spam

As you can see in the image above, the backlink in one of these comments is gscraper.com. A search on Google brings up a number of links to the domain but I didn’t bite right away since I was skeptical that what appears to be the perpetrator’s resource holds an unbiased answer. Next, I searched on “what is gscraper”. Behold one of the top returns was a youtube video promoting a fairly new application called gscraper.

The video is quite revealing. While the promoter is clearly touting the capabilities of the application to the target audience (Blackhat SEO users), it also has the effect of revealing the current state of their dubious craft to everyone else as well.

Basically the program is used to automate several tasks:
• harvest hundreds of thousands of URLs of blogs with new and recent posts
• spam them all with a generic comment that includes a backlink
• search the list to reveal the comments that got through unhindered
• harvest all of the active posts from the shorter list of open blog URLs
• spam the new filtered list for maximum spam density

Woah! Welcome to the world of “Blackhat SEO”. Sorry pal, oops you’ve scraped the wrong blog.

No doubt, this post will quickly get spammed. Advice to anyone who has a blog out there… “Batten down the hatches”!

Another Entertaining Blog for Engineers

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I was watching the latest “Mailbag” episode on Dave (That Crazy Australian Bloke) Jones’ EEVBlog wherein he mentions another Video Blog (VLOG?) “ToddFun.com”. Todd sent in a Chinese market Fluke meter for Dave to “analyze”. Buyer beware, the meter doesn’t stand up so well to Dave’s first impression. He hinted at fun future plans for it though, I think the magic smoke may be released soon!

By all means check out “ToddFun.com”. as well…

ToddFun

While Todd may not be quite as “Energetic” as Dave, if you like nuts & bolts it’s definitely one for your favorites.