Antennas Radios Amplifiers Baluns and Receiving Systems for HF
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TKO 600 transmission
Shift Problems
I enjoy amateur
radio because there
are so many things
to learn. Amateur
radio is also a
great fraternity.
You can learn a
little bit about how
I started in this
hobby on my
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Other Technical
Info Sites:
http://www.eznec.com/index.shtml
http://www.seed-solutions.com/gregordy/Amateur%20Radio/W8WWV%20Experimentation.htm
http://www.ifwtech.co.uk/g3sek/
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Some of this
site’s (W8JI.com)
contents are listed
below:
TKO 600 transmission
Shift Problems
Amplifiers
SB-221
Tank Voltages and
the parasitic
oscillation myth.
The real
explanations behind
amplifier parasitic
oscillations and
alleged damage by HF
amplifier parasitic
oscillations. Look
at voltage
throughout the tank
at frequencies
between 1 and
300MHz, and decide
for yourself.
Related article at Arcs,
what makes an
amplifier arc?
Preamplifiers
for receiving.
Measurements
of receiving
preamps. Compare
your favorite
pre-amp (text
corrections
4/27/03)
Arcs,
what makes an HF
amplifier arc?
This explains causes
of amplifier arcing
in any amplifier,
including the TL-922
amp, Ameritron amps,
Heathkit
SB220 amplifier,
and any other HF
power amplifier for
amateur or
commercial service.
Simple failures and
design or operating
shortfalls are often
explained as
parasitic
oscillations
Bandswitch
failures the
real causes and
cures of bandswitch
arcing and failures
in HF power
amplifiers that are
often attributed to
poor parasitic
suppression causing
oscillation
How
to load or tune your
HF amplifier and
why an amplifier
arcs when tuned
incorrectly
Inductors
deals with antenna
loading coils but
also applies to
amplifiers
Related page: Inductor
spice model
Relays
how to speed and
sequence amplifier
T/R relays and how
antenna transfer
relays affect
amplifier failures
Tank
Circuits two
models showing tank
voltages, currents,
loss, and phase
shift
Vacuum
Tubes how
they work in RF
power amplifiers and
why vacuum tubes arc
in amplifiers
Includes details on
3-500Z and 8877
3CX1500 A7 tubes.
Learn reasons tubes
fail in amps
Vacuum
tubes, how they
convert d-c to RF how
RF amplifier tubes
convert dc to RF
power
VHF
Parasitics
and general
stability. Is your
amplifier unstable?
If you own a TL922,
SB220 series, 30L1,
or other amps with
grid
“negative-feedback”
you will want to
read this! (rev 5PM
Feb23/03) Spice
models. The resistor
think might be
non-inductive might
not be what you
think. Includes
internal photos of
various resistors.
ANTENNAS
and antenna related
topics
Cebik
and other short
dipoles. feed line
and tuner
analysis!!
EH
antenna: the
E-H and CFA
antennas. How they
work. See how
my early theoretical
predictions and
descriptions compare
to actual field
measurements of this
most recent antenna
theory hoax!
If
you think baluns
at the inputs of
tuners are a
good idea, go
to this
W7EL link
and read the section
on current baluns.
You might be
surprised!
Another suggested
tuner link is W9CF.
Balun
and Core Selection:
(mostly
receiving) Contains
information on core
selection for
transformers and
baluns (it isn’t a
balum)
Balun,
sleeve baluns:
How a sleeve balun
works and what is
important
Balun,
transmitting: Testing
transmitting baluns
and untrue folklore
about choke,
voltage, and current
baluns. Dispelling
myth that grabbing
coax adequately
tests a balun
Baluns:
winding
methods with toroid
cores and debunking
myth that a split
winding improves
performance
Baluns:
Common-mode
noise. How baluns
can help reduce
receiving system
noise
BALUN
TEST:
Test
data on transmitting
baluns.
Beverages:
Construction,
Endfire Beverages,
Broadside Beverages,
Beverage Arrays for
low band DX and
other low noise
receiving antenna
arrays for 160
meters and other low
frequency bands.
Also see balun
and core selection
for Beverage
transformers.
Combiner
and Splitters:
Contains information
on Magic-T splitters
and combiners, how
they work and what
they do
Curtain Array:
Dipole evolution
into Lazy H, Sterba,
and other broadside
curtain antenna arrays
Detuning
Towers: A
tutorial with an
important correction
of the common error
that we adjust for
minimum
current!! (revised
slightly Feb 17,
2003)
Gain.
Stacking
(Broadside) and
end-to-end
(Collinear) gain.
How it works,
dispelling the 3dB
myth.
Lazy-H antenna:
Evolution of the
dipole into the
Lazy-H and Curtain
Arrays
Loading
Inductors: A
brief tutorial on
loading coils
(inductors) and
inductor Q
Magnetic
Loop Antennas:
receiving
Mobile
and Loaded Antennas:
Loading coils,
ground losses, and
currents in the
system. Related
page: Inductor
spice model
Power
Stroke Diesel RF
Noise:
PowerStroke
Diesel noise and how
I corrected the
problem in my 2003
F-250.
Noise
and common mode
noise. How it gets
into the receiving
system Power
line and other noise
sources
Omega
and Gamma Matching:
Contains technical
information on Omega
and Gamma matches,
impedance limits,
component selection,
component
failures
Phasing,
Crossfire: Contains
information on
cross-fire phasing
and why cross fire
phasing is superior
for broad bandwidth
low-band receiving
arrays
Phasing
Systems: A
quick discussion of
phasing
methods
Polarization
and diversity:
Think you can have
the best of the two
worlds of vertical
and horizontal?
Think again!
Radiation
and Fields:
Electric field,
magnetic field,
Fresnel zone What
the terms we use
actually describe
Radiation
Resistance:
A revised (as of Feb
14, 03) tutorial on
radiation resistance
and how it is used
and misused
Receiving
and receiving
antenna pages:
Relative ranking of
antennas for Topband
DX plus various
articles on low-band
DX receiving
antennas…including
low band receiving
antennas such as Beverage
antenna and
Beverage antenna
construction.
Elongated Loops
and other loop
receiving antennas
such as K9AY, EWE,
and flag antennas,
small Topband or HF
low noise receiving Verticals
, my
receiving antennas
(with a demo), end-fire
or cross-fire
Beverages, common-mode
noise in low
noise receiving
systems, and more.
Rhombic Antennas
Rhombic antenna:
Models and theory of
rhombic antennas and
comparisons of the
Rhombic to a
standard dipole
reference antenna.
Skin
depth: The
best explanation I
have found
Transmitting:
Contains information
on my various
transmitting
antennas, including
my eight
direction four-square
Traps:
Measurements and
models of traps,
including Coaxial
and Tribander
Antenna traps
Receivers
Diversity
reception
“diversity”
receiving using
stereo along with
some sound file
examples
Receiver
Tests of
some transceivers
and receivers. Newly
added 756PRO FT1000
MK V Kenwood TS870
(modified)
Receiver IM
improvement mods
for FT1000
FT1000D
DX
Sound files:
What some signals
sound like here
1000MP
MK V….mods
for FT1000MKV
receiver IM and
transmitter clicks
Key
Clicks
Includes sound
files of signals
with excessive
bandwidth, a
technical
description of what
causes clicks, and
mods for the
FT1000(D) and
FT1000MP.
What
Causes Clicks….The
technical cause and
what we can do about
clicks.
Keyclick-MP….
An analysis and
patch for the
FT1000MP ‘s infamous
key
clicks
Keyclicks
1000D…. An
easy and cheap patch
for the FT1000 and
FT1000D
Keyclicks
1000MP MK V….mods
for FT1000MKV
receiver IM and
transmitter clicks
Also see Radios.
Noise
Technical article
about noise and
receiving/ receiving
antennas
Power
Stroke Diesel RF
Noise:
PowerStroke
Diesel noise and how
I corrected the
problem in my 2003
F-250
MFJ-1025/1026
Technical
Information
Common-Mode
Noise issues
with feed lines, and
how to avoid
problems
MFJ-259B Alignment
instructions and
some technical
information MFJ259B.
MFJ-1025
and 1026 phasing
unit technical
information.
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County Industrial
Development
Authority
Project Brown Green
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Rollcast Energy
all pages ©2003-10 W8JI