[Amps] Sad State of the Hobby

[Manfred Mornhinweg]

Hi Lee, and all,

we are in the same boat there...

> A friend of mine has been getting himself interested in building a 
> super Full legal limit solid state amplifier.

> This evening I started researching this topic on the internet and was
>  amazed at the lack of good info on the subject.

As some of you are aware, I'm trying to develop an SDR with a nice and
interesting high power amplifer, and I stumble across the same problem:
Lack of good info.

A few days ago I got hold of 14 different books devoted to the subject 
of "RF Power Amplifiers". And it turned out that:

- All 14 of them are completely theoretical/mathematical, with
absolutely no practical circuit examples given, and most of them not
even giving any simplified schematics! Instead there are pages upon
pages of equations.

- All 14 of them centralize on 2GHz and higher, for "mobile devices". HF
is barely even mentioned, not even for medical/industrial use, let alone
communications!

- "Power" in those books means between 1 and 50 watts. Much of the space
in those books is devoted to 1W amplifiers completely implemented in a
tiny CMOS IC.

- "Broadband" in those books means either broadband modulation (data
rather than audio), or it means an RF bandwidth of maybe 30%. What we
hams understand by "broadband" - several octaves - isn't even mentioned
in most of those books. Two or three briefly mention it - and go on
giving several dozen pages of differential equations to explain their 
theoretical operation.

- Not much is said about practical, real-world problems such as stray
inductances, leakage inductances, and cooling issues.

If I had gotten these books on paper, I would use them for fuel in my
stove. But since I got them as PDF files, they aren't even good for that!!!

> I did a search at the ARRL web site and they have a 1000 watt amp 
> article in their QEX magazine but that was way back around 2002 or 
> so.? OLD TECHNOLOGY! What is this?? Nothing for 15 years?? I knew the
>  ARRL was falling behind in their technical articles but 15 years
> with no amp construction article?? Man, this is truly sad!?

ARRL can only publish what we hams write and submit to them. With ever
fewer hams building anything, of course there are ever fewer articles
available for publication. But that's just half of the story. A fair
number of years ago I published an article in QST and the Handbook, and
another in QEX. I noticed a certain resistance by ARRL to publish
articles they deem "too difficult" for their readership. In other words,
ARRL was knowingly dumbing down their publications in order to keep them
accessible to the least knowledgable hams. And that was 20-15 years ago.
It seems that since then it only got worse. Eventually I discontinued my 
membership in ARRL, because the only benefits for me as a foreign ham 
were the publications, and they were no longer worth their cost.
What's even more terrible: ARRL is probably right, in that today's 
average QST reader simply doesn't want any articles about building 
radios nor amplifiers! They want to buy and use, not build. And that's 
true for most hams in the world.

> I suspect there are no decent articles on building one anywhere.?

"Decent" is the difficult part. There are construction articles on the
web, but many of them are incorrect, incomplete, feature very poor 
design, or are trivial.

> This hobby has truly sunk to a new low.

Worse: It's dying out.

> Even on this reflector I can't remember any talk about modern day
> amps and how to build one using the newly offered high powered FETs.

I'm on this forum because it's the one providing the most amplifier 
construction info in the world, as far as I know. Which means that the 
other places discussing this technology have even less useful contents 
than this one! There are some truly knowledgeable people on this forum. 
And also a lot who don't know much about amplifier building, being more 
amplifier users than builders, but tolerate those of us who occasionally 
write something technical... And many who are very knowledgeable about 
tube amplifiers but not solid state ones.

About the state of the hobby in general, let me just state these sorry 
facts:

- In my country there are currently about 4000 licensed hams. 20 years 
ago there were 15000.

- Many radio clubs here have disappeared, because their last remaining 
members died.

- We have a daily friendship net on 40 meters. One of the key points of 
that net is informing about last day's Silent Keys. In average there is 
about one SK per day. And not nearly enough newcomers to fill the ranks.

- In several other countries in my region, such as Bolivia and Paraguay, 
ham radio seems to have died out. It's ages since I last heard a 
Paraguayan ham, and in the last 10 years I have heard only a single 
station with a Bolivian callsign - and that turned out to be a foreigner.

- 20 to 40 years ago, whenever there was decent propagation on a band, 
there was ham activity to be heard. Nowadays one can notice good 
propagation by increased band noise and by various intruders in our 
bands, while most of the time there isn't a single ham signal. The 
exception is contest weekends, when the contest bands fill to the brim. 
This proves that there still are a considerable number of hams in the 
world, but most of them are inactive except during contests.

Make the exercise: Scan through all bands, listen briefly to each QSO 
you hear, and note down how many of them are about technical, 
ham-related matters, specially about equipment construction. If you hit 
the 1% mark, you are lucky. And that should be one of our main themes, 
if not THE most important one! Remember the definition of a ham...  not 
much left of that.

I'm no exception: 35 years ago I built at least 3 or 4 pieces of ham 
equipment a year - everything from power supplies to complete 
transceivers. Nowadays I have a single ham project going - this high 
power SDR - and it looks like it will take me the rest of my life to 
complete it, if I do at all. Instead of working on it, I waste my time 
whining on this forum.

So, Lee, you are not alone in lamenting the state of the hobby.

Manfred, XQ6FOD

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