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Sent: Sunday, January 26, 2020 9:20 AM
Subject: Re: [TekScopes] 11801 questions - funny fan noise and light
Ragnar asks: Are there any schematics on these  boxes to be found?
By the 1960s Tek's Service Manuals (SM) were the finest in the industry.
They were a major selling point for Tek products. They were specifically
designed to give you all the information necessary to fix the instrument.
With the SM it was relatively inexpensive to maintain Tek instruments in
calibrated condition for a long time after they were purchased. The longer
those instruments could be maintained in good condition the lower the Total
Cost of Ownership (TCO) for the company that owned it. Eventually someone
would realize that the SMs were adversely affecting sales. With such good
SMs no one was in a hurry to buy new instruments from Tek when it was easy
to keep their old instruments calibrated and working perfectly.
In the mid-1980s someone in management did realize that Tek could make more
money by NOT including schematics in their service manuals. By the time the
11000 series of scopes appeared in 1986 schematics were banned from the
Service Manuals for new products. As far as I know there are no schematics
available anywhere for the 11K scopes. I tried on one occasion to get the
set for an 11K scope from someone at Tek but they were unable to locate
them. Since then Tek has tightly controlled the schematics for all of the
11K scopes and probably all other products as well. If a schematic set were
ever to escape from Tek's "clutches" and be released "into the wild" for a
supported product then returning it to the factory for repair would not be
the only way to get it fixed.
The disappearance of the schematics from Tek's service manuals was
impossible to miss when it happened. It occurred during a period in the
latter half of the 1980s when Tek was struggling financially with layoffs,
spin-offs, and decreased earnings almost every quarter.
When a product support department is a Cost Center the company recognizes
that good support is an intrinsic cost of producing a good product. The
company can charge more for its products because of the superior support
provided for them. The cost associated with providing this support is
recouped indirectly by a higher price the customer will pay for a
When a product support department is a Profit Center it is expected to
generate revenue for a company by charging for support. This change will
help a struggling company's bottom line for a few years - which was probably
why Tek chose to do it in 1986 - but eventually it will result in a loss of
customers and greater competition. In other words, this will come back to
bite you one day. Presumably the manager who is credited for this great idea
will also know he has a few years to find a job elsewhere before the real
damage he has done becomes apparent to the board.
Why did Tek remove the schematics?
* Without schematics Tek products have to be returned to the factory or
nearest repair center for repair. This is inconvenient for the customer
because travel time back and forth can be greater than the repair time. It
is dangerous because the instrument can be damaged in transit. It is
expensive to crate up and ship a large, heavy instrument. In addition, since
the factory has a monopoly on repairs, they can charge more than the
customer's in-house repair department costs. This increases the customers
TCO. Tek makes money but it is at the expense of the customer who eventually
will realize that Tek products are becoming as expensive to own as other
similar products from HP, LeCroy, etc..
* More importantly, without schematics, Tek can arbitrarily shorten the
useful lifetime of their products by declaring a product obsolete and ending
the repair service for it each time they introduce a new product that
improves on the old one. By no longer providing repair service for obsolete
products customers can be pressured to purchase the new replacement the next
time their existing instrument breaks. Tek makes more money by selling new
products to replace the old ones they will no longer repair. The customer's
TCO goes up a lot in this scenario.
Each time the TCO goes up for the customer it encourages him to look at
competitive products and even low cost products from places like China which
do not have the engineering excellence Tek is (was?) famous for. By making
support a Profit Center Tek makes more money in the short term but loses
customers in the long term when they purchase competitive products with a
lower TCO. In the very long term Tek loses the low end segment of the market
to new competitors who see an opportunity to enter it with 1) products that
are cheaper than Tek can make, and 2) products the customer can justify
buying because they understand it was meant to be recycled rather than
repaired when it eventually breaks. The TCO is irrelevant for throw away
In the very long term, supporting customers with a Profit Center model, will
drive customers to reputable competitors with similar products that offer
them a choice of in-house support vs. Tek Profit Center support. Some
customers will realize they have another choice - buy an inexpensive
throw-away instrument for 1/4 to 1/3 of the price Tek charges. This creates
more competition at the low end of the marketplace where the profit margin
has eroded so deeply that Tek is no longer competitive.
Dennis Tillman W7PF