That was a poor choice of word on my part -- I apologize. I meant
"fundamental". Wes explains how things work on a fundamental level. But
it isn't a textbook of pure basic theory. It relates working circuits to
their fundamental roots.

I took an expensive advanced microwave design short course some years
ago. The instructor was a person who'd worked in the field for many
years. With disturbing frequency, he would come out with statements I
knew to be false and, after some questioning, I discovered that he
didn't have any idea of the fundamental (or basic) criteria for
oscillation. He'd been designing oscillators for years without really
knowing what made them oscillate. This might have been a case of someone
who read the "intermediate" texts without ever reading the "fundamental"
ones.

This isn't to say that people can't design useful things without fully
understanding what they're doing -- I'm convinced that a majority of
useful things are created this way. But you can do an awfully lot more
if you have a real fundamental understanding of how things work. The
most truly creative and innovative engineers I've known have this
understanding -- and an intense curiosity about things they don't know.

I guarantee there's plenty of "intermediate" and "advanced" level
information in that book, and even without knowing anything of your
background, I also guarantee there's plenty of "fundamental" knowledge
you missed somewhere along the line and will pick up from this book. If
I'm wrong, let me know and I'll buy the book from you. I can always use
another copy.

Roy Lewallen, W7EL

Paul Burridge wrote:
On Fri, 15 Oct 2004 11:39:27 -0700, Roy Lewallen
wrote:
. . .
I highly recommend it for anyone interested in understanding electronic
circuits on a more basic level. It nicely complements his other books,
and it's a bargain at the price.


Oh, blast! You were doing so well there for a while, Roy. Now you've
gone and spoilt it all by using that word "basic." I was hoping for
something at least "intermediate" and I don't really see how "basic"
and "RF design" sit easily together in a single description. Please
tell me it's useful for more advanced stuff too!

On Sat, 16 Oct 2004 13:36:59 -0700, Roy Lewallen
wrote:


I took an expensive advanced microwave design short course some years
ago. The instructor was a person who'd worked in the field for many
years. With disturbing frequency, he would come out with statements I
knew to be false and, after some questioning, I discovered that he
didn't have any idea of the fundamental (or basic) criteria for
oscillation. He'd been designing oscillators for years without really
knowing what made them oscillate. This might have been a case of someone
who read the "intermediate" texts without ever reading the "fundamental"
ones.

This isn't to say that people can't design useful things without fully
understanding what they're doing -- I'm convinced that a majority of
useful things are created this way. But you can do an awfully lot more
if you have a real fundamental understanding of how things work. The
most truly creative and innovative engineers I've known have this
understanding -- and an intense curiosity about things they don't know.

well, said! But isn't this the very frequent feeling one gets from
reading amateur radio magazines? The constructors (I wouldn't use the
word "designer") should have constructed and tested at least 10 equal
constructions, or have similar experience before publishing an idea,
which may later turn out that might not be repeatable

Too often constructions are published when it is a hope rather than
experience that it is a good idea. For somebody it is more important
to use wellknown devices than trying to propose something else

73, Jan-Martin

---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

On Sat, 16 Oct 2004 13:36:59 -0700, Roy Lewallen
wrote:

[snip]

Thanks for the clarification, Roy. I'm sure your kind offer won't be
necessary, though, as it now sounds like pretty much the kind of
source I'm looking for. The companion diskette is included, but I
doubt there will be anything on it that Reg hasn't already covered in
his amazing collection of programs for radio and ariel design.

p.
--

"What is now proved was once only imagin'd." - William Blake, 1793.

Few people appreciate the vast difference between making something that
sort of works, once, and a design that can be produced by the thousands
with nearly every one working, fully meeting specifications, and being
reliable under a wide range of operating conditions. Those of us who
have made a living by developing quality products such as test equipment
have a full appreciation for this, and go about the design process in a
very different manner than a person accustomed to making a one-off
circuit for home use.

Many, or most, of the books oriented toward amateurs are written by
people who haven't developed the background or discipline to produce
reliable, repeatable circuits. Magazine articles are even more in this
category. Some circuits found in handbooks have perhaps never been
actually built or tested by the author, even in a quantity of one.
That's not a condemnation -- after all, this is amateur radio, most
offerings are free, and the designs are adequate for a lot of users.
Hopefully -- although I'm afraid a bit wishfully -- some builders at
least have enough technical know-how to take care of minor design flaws.
Nonetheless, it's really a treat when we're given a circuit or an
explanation by a truly professional engineer whose approach to circuit
design is one of making reliable, repeatable circuits. The chances of a
copy of the circuit working the first time, as predicted and claimed,
are much higher than for a design built once with little understanding
of how it works or what its limitations and weak points are. And the
deeper the designer's understanding of the fundamental principles
involved, the greater the chance that he's accounted for and designed
around potential problems in repeatability and operating environment.

That's one of the reasons I like and heartily recommend Wes' books and
other writings. I've known him as a friend and as an engineering
colleague for 30 years now. He's one of the very best, and we're lucky
to have access to a fraction of what he's learned.

Roy Lewallen, W7EL

J M Noeding wrote:

well, said! But isn't this the very frequent feeling one gets from
reading amateur radio magazines? The constructors (I wouldn't use the
word "designer") should have constructed and tested at least 10 equal
constructions, or have similar experience before publishing an idea,
which may later turn out that might not be repeatable

Too often constructions are published when it is a hope rather than
experience that it is a good idea. For somebody it is more important
to use wellknown devices than trying to propose something else

73, Jan-Martin

---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

On Sat, 16 Oct 2004 15:17:47 -0700, Roy Lewallen
wrote:



Many, or most, of the books oriented toward amateurs are written by
people who haven't developed the background or discipline to produce
reliable, repeatable circuits. Magazine articles are even more in this
category. Some circuits found in handbooks have perhaps never been
actually built or tested by the author, even in a quantity of one.
That's not a condemnation -- after all, this is amateur radio, most
offerings are free, and the designs are adequate for a lot of users.
Hopefully -- although I'm afraid a bit wishfully -- some builders at
least have enough technical know-how to take care of minor design flaws.
Nonetheless, it's really a treat when we're given a circuit or an
explanation by a truly professional engineer whose approach to circuit
design is one of making reliable, repeatable circuits. The chances of a
copy of the circuit working the first time, as predicted and claimed,
are much higher than for a design built once with little understanding
of how it works or what its limitations and weak points are. And the
deeper the designer's understanding of the fundamental principles
involved, the greater the chance that he's accounted for and designed
around potential problems in repeatability and operating environment.

That's one of the reasons I like and heartily recommend Wes' books and
other writings. I've known him as a friend and as an engineering
colleague for 30 years now. He's one of the very best, and we're lucky
to have access to a fraction of what he's learned.

When amateur constructors are mentioned, it is not only those who do
strange things. While many large telecommunication and instrument
factories like HP, Tektronic, Siemens, Wandel&Goltermann,
Rohde&Schwartz, LME, Philips, Telettra seem to have certain rules to
follow and you may even see certain ways the different factory solves
the problems, it is some very large companies in Norway, Great
Brittain and elsewhere who make rather strange solutions.

One Italian company forgot to put transient protection over a relay,
and the driver transistor was damaged ever so often. I've maintained
many different transmitters which were almost impossible to tune up
after replacing parts because the impedances changed a lot, adding a
resistor in the base circuit improved on this. A wellknown Norwegian
radiolink manufacturer designed local oscillators in 6-8GHz using
2N3866 with over 1.5W power consumption, a buffer with the same and
operated in class C, the next doubler to 200MHz in class C and a
2N3866 as well, and a 2N3375 in class C. The first and third
transistors were critical and had to be replaced every two years, and
the signal on 6cm was so noisy that SM6ESG couldn't find any beat
note. He modified the stages to class A, reduced the drive level on
all stages and the heat was considerable lower, and at least the
oscillator noise very much improved

So, one shouldn't only blame the amateurs for bad constructors, but
sometime the manufacturers may even be worse

73,
Jan-Martin
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

I obviously can't speak for the Italian or Norwegian companies you
mention, but I do have the direct experience of 17 years of circuit
design and project engineering management at Tektronix. It's hard to
imagine experiences like yours happening with Tek equipment.

During the time I worked there, and presumably up to the present, Tek
had what they called the "phase" system. The engineers would do their
very best to design the product to meet all the advertised
specifications, plus additional non-advertised in-house specs. These
included temperature, vibration, shock, humidity and other environmental
specs; certification by various safety agencies; and EMC requirements,
in addition to detailed electrical performance specs.

When this design was complete, a meeting was held. Attendees included
representatives from design engineering, marketing, product safety,
component and evaluation engineering, and others. Only by consensus of
this group was the milestone declared to have been completed.

This was just the beginning, though, of the first phase, called "A
Phase". A number of instruments were built, typically around 25 to 50.
Some were sent to the environmental lab to test performance over the
range of specified environmental conditions. Others were shaken and
shocked. Others were studded with temperature probes and tested for
excessive temperature at many internal points. A few were put on
accelerated long-term reliability testing at a greatly elevated
temperature. Some were cycled on and off at high temperature. The design
was carefully analyzed by the evaluation engineering group, looking for
overstressed components. And many of the units were tested against the
full specification list, to insure that they fully met every spec.

During this phase, many problems were of course found and fixed. The
engineers would generate change orders describing the fixes, and the
test units were modified accordingly.

When it was believed that the units all met the many requirements,
another milestone meeting was held. Again if the attendees agreed, the
milestone was declared met, and "B Phase" began.

B Phase was largely a re-run of A Phase. Again, a sizeable number of
instruments were built and fully tested. Problems which were found were
corrected. Only at the end of this phase was production started.

Production often started with a pilot build. The first hundred or so
instruments were given extra scrutiny, temperature cycled, and otherwise
tested in a way to overstress them. These instruments normally became
demo units for the sales force, and some were retained by engineering
for internal use.

After pilot production, volume shipment finally commenced. Some large
companies required an incoming inspection test where every one of the
electrical performance specifications was checked, and the instrument
rejected if any failed. I once had the job of collecting test equipment
and writing a procedure for customers to use for testing our 50 GHz
bandwidth sampling head to specification, and it was very difficult to
find equipment capable of verifying the performance. We weren't able to
claim 60 GHz bandwidth even though we were pretty sure our units would
do it, because we couldn't find a way for us or the customer to verify
it at the time.

After the units were in production, each field service center kept
records of repairs, and which components failed. They were sorted by
circuit number (e.g. Q123) and part number, as well as by instrument and
board. If any part showed a high failure rate, the design was modified
and future instruments were built using the new design.

I know that other quality manufacturers have similar development systems.

That's why a Tektronix instrument costs a lot more than some others. The
existence of companies putting out the shoddy sort of stuff you mention
shows that some people are willing to trade quality for price. That's
their choice.

But the environment I described is the one I, and Wes, are accustomed
to, and it's what our designs had to get through.

Roy Lewallen, W7EL
(formerly Principal Engineer, Tektronix)

J M Noeding wrote:
On Sat, 16 Oct 2004 15:17:47 -0700, Roy Lewallen
wrote:

When amateur constructors are mentioned, it is not only those who do
strange things. While many large telecommunication and instrument
factories like HP, Tektronic, Siemens, Wandel&Goltermann,
Rohde&Schwartz, LME, Philips, Telettra seem to have certain rules to
follow and you may even see certain ways the different factory solves
the problems, it is some very large companies in Norway, Great
Brittain and elsewhere who make rather strange solutions.

One Italian company forgot to put transient protection over a relay,
and the driver transistor was damaged ever so often. I've maintained
many different transmitters which were almost impossible to tune up
after replacing parts because the impedances changed a lot, adding a
resistor in the base circuit improved on this. A wellknown Norwegian
radiolink manufacturer designed local oscillators in 6-8GHz using
2N3866 with over 1.5W power consumption, a buffer with the same and
operated in class C, the next doubler to 200MHz in class C and a
2N3866 as well, and a 2N3375 in class C. The first and third
transistors were critical and had to be replaced every two years, and
the signal on 6cm was so noisy that SM6ESG couldn't find any beat
note. He modified the stages to class A, reduced the drive level on
all stages and the heat was considerable lower, and at least the
oscillator noise very much improved

So, one shouldn't only blame the amateurs for bad constructors, but
sometime the manufacturers may even be worse

73,
Jan-Martin
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

And what happened when the management/sales team decided they were
going to deliver anyway, and asked you in a _meaningful_ manner
whether you thought that your objections to the milestone being declared
were really in the company's best interests or in your own personal
best interests?

"Roy Lewallen" wrote in message
...
When this design was complete, a meeting was held. Attendees included
representatives from design engineering, marketing, product safety,
component and evaluation engineering, and others. Only by consensus of
this group was the milestone declared to have been completed.

On Sun, 17 Oct 2004 13:55:15 +0100, "Airy R. Bean"
wrote:

And what happened when the management/sales team decided they were
going to deliver anyway, and asked you in a _meaningful_ manner
whether you thought that your objections to the milestone being declared
were really in the company's best interests or in your own personal
best interests?

"Roy Lewallen" wrote in message
...
When this design was complete, a meeting was held. Attendees included
representatives from design engineering, marketing, product safety,
component and evaluation engineering, and others. Only by consensus of
this group was the milestone declared to have been completed.


apart from Tek and certain others which Roy describes, I believe that
some economists look at the balance between number of components used
and trade-off in production, so much more equipment would pass the
control if certain components were added.

What I actually meant, but perhaps didn't fully express was that you
may study the circuit diagrams and have a feeling which manufacturer
has designed it, they follow certain techniques and technical
management.

On the other hand one may experience that HP and Tek uses some extra
components which are difficult for the average constructor to explain
or understand the function for, and one may experience that even among
the amateurs somebody manage some technique which almost nobody else
can copy - not even very experienced persons, may I mention SM5BZR
Leif's techniques, it is many constructions, they may look so easy,
but one often need some more deeper understanding to succeed, what
say's G3SEK?

73
Jan-Martin
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm

J M Noeding wrote:
On the other hand one may experience that HP and Tek uses some extra
components which are difficult for the average constructor to explain
or understand the function for,

They don't have a legal obligation to explain their detailed circuit
design... but you can learn a lot by trying to work it out for yourself.

and one may experience that even among the amateurs somebody manage
some technique which almost nobody else can copy - not even very
experienced persons, may I mention SM5BZR Leif's techniques, it is many
constructions, they may look so easy, but one often need some more
deeper understanding to succeed, what say's G3SEK?

I don't have any personal experience of copying Leif's designs (assuming
this is SM5BSZ we're talking about) but they have been widely copied. It
just takes everyone else a whole lot longer... so he's still way out
ahead.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

In my experience, never. And I never heard of it happening, ever.

When the heat got turned up, everyone worked nights and weekends until
the goal was met. If we couldn't do it, the project was canceled.

Roy Lewallen, W7EL

Airy R. Bean wrote:
And what happened when the management/sales team decided they were
going to deliver anyway, and asked you in a _meaningful_ manner
whether you thought that your objections to the milestone being declared
were really in the company's best interests or in your own personal
best interests?

"Roy Lewallen" wrote in message
...

When this design was complete, a meeting was held. Attendees included
representatives from design engineering, marketing, product safety,
component and evaluation engineering, and others. Only by consensus of
this group was the milestone declared to have been completed.