I don't intend to start a war, however based on my observations over the
last 2 decades (at least) in going to rallies (what Americans call
hamfests) and my observations of some of the questions which crop up on
the ham radio newsgroups the average ham is too lazy to do anything.
Research on even the simplest thing is out of the question - much easier
to ask the question on a newsgroup and get someone to give you the
answer, perhaps a short course in using a search engine might be the
solution? And as for things like co-axial relays. Vacum capacitors,
ceramic switches, link coupling and all the other mysteries of ham
radio, well sometimes it's talking about some thing from outer space.
Many times I've watched so called "hams" pickup a very rare and sought
after item and look at it in wonderment, not having the faintest idea
what it is.
Often I've discovered really priceless items at rallies which have not
even been given a second glance by the average ham who should, if he
knew what he/she was about grab at the first chance.
I can quite understand the trade-off between time and other demands but
in all honesty the commercial equipment, especially when it comes to
high power isn't worth a light, unless you pay top dollars for it, as an
example a so called 1200 watts commercial ATU I bought whose power meter
detector burnt out at 400 watts of 10 metres RF (into a dummy load at 1
to 1 of course), subsequent examination revealed shoddy construction
with no way of handling 1200 watts at 50 ohms even down a piece of wire
which is just about capable of carrying 2 amps leave alone 5 amps or
thereabouts - which so called "engineer" designed this piece of junk?
For the last few weeks I've been investigating dummy loads especially
the so called high power types. What has mystified me is that many of
these so called high power types (1 to 2.5Kw) and with the exception of
the oil filled cheaper types are rated for ONLY 40 seconds to a minute!
Absolutely astonishing... what use is a dummy load for a minute or less
especially when testing/tuning out an amplifier or measuring it's
efficiency? And the price of these amazing pieces of equipment 200
dollars plus, to call some of this equipment a 1, 1.5 or 2.5Kw dummy
load is bit of a joke in my view.
Some of the comments which appear on Rich Measures web site about
commercial equipment are well justified, rigs with so called fast break
in using standard power relays to switch linears, no soft start for
power supplies, short circuiting HT lines as a safety measure, band
switches that arc because there is inherent in the design of an
amplifier a cause for VHF parasitic.
Even in the UK "economy measures" are used to build and sell equipment
and increase profit margins. I have in front of me a receipt dated 1993
for 2 Toroidal HT transformers used in the construction of a commercial
HF amp and bought by me at a certain specification for a power supply I
was constructing. When I eventually tracked down the manufacturer of
these toroids and discussed there power handling capabilities he was
rather amazed that they had been sold to me quoted at the power output
at which I'd bought them, I well remember the comment at the time -
"that's pushing it a bit". Commercial equipment is built to a price.
home-brew is built to a specification.
And with that I'll get off my soapbox
Happy and prosperous New Year to all!
Paul
In message <3.0.6.32.20001228195722.007ae360@contesting.com>, Bob
Marston <k1ta@contesting.com> writes
>
>Paul wrote:
>
>> Better if we all built our own,
>
>You're pretty close Paul. The fact of the matter is that most hams are too
>rich and too lazy to attempt to build their own amp. While the first such
>undertaking would not be done from a point of economic savings, one would
>actually learn quite a bit from practical experience. Well worth the extra
>cost
>
>K1TA
>
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>
>
--
To try and not succeed is better than not to try at all (Anon)
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
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Administrative requests: amps-REQUEST@contesting.com
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