Hello Joe,
The design is slightly different.
I use now 2 J310's parallel and Rs = 560 ohm.
Supply voltage can be anything between 4 and 20 V, whilst the current draw is 7
mA.
The output transformer is wound bifilar on a FT-37-43 with 20 turns, but a high
mu toroid will
work equally well. A BN-73-202 binocular core with 10 bifilar turns can also be
used.
VLF performance can be enhanced by increasing the 1M gate resistor to 10M or
higher.
73,
Roelof, pa0rdt
The following section of this message contains a file attachment
prepared for transmission using the Internet MIME message format.
If you are using Pegasus Mail, or any other MIME-compliant system,
you should be able to save it or view it from within your mailer.
If you cannot, please ask your system administrator for assistance.
---- File information -----------
File: pa0rdt-Eco-Mini-Whip.pdf
Date: 3 Jul 2018, 14:17
Size: 130431 bytes.
Type: Unknown
pa0rdt-Eco-Mini-Whip.pdf
Description: Binary data
|
