On 4 Sep 2003 08:50:24 -0700, (Qas) wrote:

Hi,
I am new to ham radio. Well I found lots of QRP receiver circuit on
web, I tried to build some. Everything going to be OK, except making
coil inductors. I don't know how to calculate them, with type I need
(air core or slug tuned), what a difference between coil and RF choke.
Let's assume I need a 100uH coil. How to star making it. I looked for
factory made coil at my radio shack store, but I only found bobbin for
coil.

If you know any interesting link on this topic, please let me know.
I'll appreciate any comment or help.

Thanks in advice,
Edgar
73


Check out this website, its quite useful and has many different java
calculators for finding the inductance values of both toroid and air
form coils. I used the calculator to create a 3uh coil and it came out
pretty darn close to what I intended. (never bridge measured it
though)

http://eweb.chemeng.ed.ac.uk/jack/radio/projsoft.html

mike

The inductance, length, diameter, wire size, number of turns, and much more
information on single-layer coils of any proportions, long and thin, short
and fat, can be accurately calculated using program SOLNOID3.

Q, self capacitance, self resonant frequency, tuning capacitance for a
particular frequency, temperature-rise for given applied RF volts, etc. can
all be calculated. Covers mini-coils in UHF receivers to high-power
transmitter tank coils, antenna tuners and traps.

You will never need another solenoid calculator. Beats them all!

Download in a few seconds directly to an icon on your desktop, small
self-contained, user friendly program SOLNOID3 from website below. No
unzipping inconvenience. Run immediately. No training course needed.

Go to the "Download from here" page and browse through a list of other
programs written to professional standards available.
----
=======================
Regards from Reg, G4FGQ
For Free Radio Design Software
go to http://www.g4fgq.com
=======================

The inductance, length, diameter, wire size, number of turns, and much more
information on single-layer coils of any proportions, long and thin, short
and fat, can be accurately calculated using program SOLNOID3.

Q, self capacitance, self resonant frequency, tuning capacitance for a
particular frequency, temperature-rise for given applied RF volts, etc. can
all be calculated. Covers mini-coils in UHF receivers to high-power
transmitter tank coils, antenna tuners and traps.

You will never need another solenoid calculator. Beats them all!

Download in a few seconds directly to an icon on your desktop, small
self-contained, user friendly program SOLNOID3 from website below. No
unzipping inconvenience. Run immediately. No training course needed.

Go to the "Download from here" page and browse through a list of other
programs written to professional standards available.
----
=======================
Regards from Reg, G4FGQ
For Free Radio Design Software
go to http://www.g4fgq.com
=======================