Re: Where have all the Schematics Gone?

Glenn Little

I bought a number of 2 GHz amplifiers at a hamfest.
I called the customer service number for the company.
The person in customer service sent me the checkout info.
When that package arrived, I called back about schematics.
He said that they had none.
I asked if he wanted schematics and he replied to the affirmative.
It took about a month of on and off time to generate the schematics.
When I emailed them to him and called to see if he had received them, he asked what I intended to use the amplifier for.
I told him amateur radio.
He then told me what circuits to disable and how to disable them to eliminate the pre distortion.
He was really helpful just crippled by lack of documentation.


On 1/29/2020 6:26 PM, KeepIt SimpleStupid via Groups.Io wrote:
I called tech support for a Nuvo NV-MI1 mute interface for a doorbell and phone

I asked how it worked and what the output was.
The tech support guy was flabbergasted that he had no information on the device.In fact, he even asked me if they made it.

On Wednesday, January 29, 2020, 3:09:32 PM EST, David Kuhn <> wrote:
I agree. At GE Inspection Technologies, the same thing happened after GE
purchased us.  Even our Sales Representatives with their own authorized
service departments could not get schematics.  Then the factory repair
service became a profit center and part prices went through the roof.
Well, GEIT is not more.  What is left of the company is a shell of itself.
The US Plant in Pennsylvania shut down, production moved between Southern
Ireland and Slovakia.  Service, without the experienced techs to the
Houston, TX area.  Now their name changed (GEIT is no more) and their
product offering a ghost of what it used to be.  Meanwhile, their
competitors are going great guns.

As far as Chinese Scopes. Siglent is quite good.  Even their 200MHz economy
scopes are very good and beautiful and inexpensive.  The displays are
outstanding!  The only reason I keep purchasing 20+ year old TDS3000
series scopes in the ability to set the mid reference levels when measuring
pulses.  In the UT industry, the pulse widths are measure at the 90%
reference levels verses the standard 50%.  I was in email with Siglents
tech support and engineering for a year.  They understood what I needed.
New firmware releases would come and still not that ability.  The best they
ever did was show a Python example of reading the waveform in and then I
could "calculate" the width at 90%. I was so frustrated. I do write a lot
of support code in VBA and VB6 that perhaps I could have done that, but I
could not make heads or tails out of their code example.  I really think it
was pure subterfuge.  I gave up and relegated the Siglent as a back-up;
this year, I will not even get it calibrated.  If they ever gave me the
ability to set the mid reference levels to whatever I wanted them to be, a
$700 brand new Siglent could easily replace a brand new $10K+++ Tektronix
TDS3000C series, or even used TDS3000 series.

On Sun, Jan 26, 2020 at 6:33 PM Dennis Tillman W7PF <>

Message #163848
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 [11801] 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
well-supported product.

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
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
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,
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
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
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
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
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
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,
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

Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV AMSAT LM 2178
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"

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