Have spent much of my active tenure as a ham operating from club
stations, I can attest to some of interesting techniques folks sometimes
use when tuning amplifiers. Back at Ohio State, we had one fellow
fom Argentina who stopped by the club once a week to keep a 21 MHz
sked with family members in LU. Near as I could tell Eduardo's tune up
procedure for the TL-922 consisted of setting the band switch to "21"
and moving the power switch from the "off" to the "on" position.
Fortunately for us, he ran very light on the drive control.
Another good story my girlfriend told me was a conversation overheard
at a then local Best Buy in Florida. A couple was at the customer service
counter complaining that their new computer would not work. The CSR
was then seen to pull a IEC power cord still wrapped in plastic from the
computer's box. Upon seeing the pristine power chord wrapped in plastic
the wife loudly exclaimed "Harold, you idiot!".
None of us are immune of course. When I went to Ohio State and joined
the Amateur Radio Club, I had to be "trained" how to tune a PI-network,
despite the fact that I had held an Advanced Class Amateur Radio license
for over 5 years . All my on the operating experience prior to that was with
a solid state rig.
I observed similiar naviety when working part-time for the Electrical
Engineering Department at OSU under the work-study program. I was put
in charge of handing out parts and test equipment to students in a senior
level digital design course. A lot of the students thought I was a graduate
student because I was running around teaching them how to use the
oscilloscopes and do some basic troubleshooting of their circuits. At the
time, I was still taking pre-major course like Calculus and Physics and had yet
to take my first EE course. Nothing I was doing was rocket science. When it
came to Carnot maps and state machine design, I was clueless. For many
of these students though, this was their first real exposure to "hands on"
circuit design and the use of test equipment. I had the advantage of 6 years
of ham radio tinkering.
Dave Rutledge, KN6EK EE professor at Caltech has addressed the problem
very well. He teaches a sophomore level EE course using the Norcal 40 QRP rig.
Students actually build, troubleshoot, and test a real live working amateur
transceiver as part of their coursework. As Dave puts it, "College students
nowadays typically begin the study of electrical engineering with little
experience in building electrical or mechanical systems. They have not tinkered
with cars or built ham transceivers. This makes it difficult for students to
appreciate the relative importance of different topics and to understand how
the different parts of a system go together."
Mike, W4EF................
----- Original Message -----
From: "Tom Rauch" <w8ji@contesting.com>
To: <amps@contesting.com>; "dcckc" <dcckc@ncn.net>
Sent: Sunday, October 15, 2000 5:55 AM
Subject: Re: [AMPS] a sticky issue.
>
> > Remember in the last few days we have been told equipment has to be
> > designed for the cheap and the ignorant
>
> Actually that is true. It doesn't mean everyone doesn't know how to
> tune a PA or is cheap, but the fact is many people don't. You'd be
> amazed at the calls!
>
> One fellow bought a CE approved AL811H that has a plug-in power
> cord. He connected the amp to 12 volts through the 12 volt
> accessory jack, and complained he could get the meters to light
> but couldn't get any output.
>
> It took about a half-hour to figure out he never even took the line
> cord out of the box and plugged it in!
>
> Now that doesn't mean all hams are that inexperienced, but it's a
> new world out there. This is becoming more and more like
> consumer electronics than a technical hobby, and don't kid
> yourself.
>
> Things have to be planned for that trend, whether we like it or not. If
> that offends you, too bad. Better get used to it.
>
> > >This should be no surprise.
> > >I have the 10-20 meter section of a AL-1500 tank coil in my left hand as
> > >I type. I can totally conceal it by wrapping my fingers around it. It is
> > >made out of square bent tubing.
> > >
> > >(((73)))
> > >Phil, K5PC
>
> You can put any size of tank coil you like in the AL1500, and you
> won't change efficiency even a couple percent. That includes
> eliminating the switch and making it a monobander.
>
> There is a fair efficiency improvement to be gained on some early
> models that used a single RG-174 cable from the tube to the tuned
> input. That cable needs to be replaced with 25 ohm or lower Z
> cable, or have two cables parallelled, that'll pick things up about
> 10% or so on ten meters. Later models (post 1990) have that
> change.
>
> The 50% Rich claims could be typical exaggeration, or something
> from early production.
>
> The "88 ohm" bypass capacitor can be changed top anything that
> makes Measures "feel all warm and fuzzy", and nothing will
> change.
>
>
> 73, Tom W8JI
> w8ji@contesting.com
>
> --
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>
>
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