Operation and Installation Instructions N2VZ Enterprises
Turbo Tuner
Web:
WWW.N2VZ.com
Page 2 of 4 Tel: 609-249-3875
Eml:
Theory of Operation:
The Turbo Tuner is designed to allow automatic Tuning and control of screwdriver antennas based on
finding the minimum SWR for the current operating frequency. This is accomplished by using the
Tune function of the radio to supply RF power while the Turbo Tuner moves the screwdriver antenna
in the correct direction based on the operating frequency and looks for the minimum SWR. Once the
minimum SWR is found, the transceiver is placed back in receive mode automatically.
INSTALLATION:
Yaesu setup:
Yaesu Menu Settings – Menu item 20 must be set to “Tuner”. Menu item 85 must also be set to
“Tuner”.
To get into Yaesu extended menu on the FT-857/897 Press and hold the “F” Key. You will now be in
extended menu mode. To leave the menu press and hold the “F” key again.
Turbo Tuner Setup:
The next step is to set the dip switches to configure the Turbo Tuner to operate with your screwdriver
antenna configuration.
Access to the dip switches is accomplished by removing the 4 Phillips head screws located at the
bottom of the Turbo Tuner enclosure. Once the 4 screws are removed, lift off the top cover and you
will see the 6 position dip switch located on the printed circuit board next to the fuse.
Dip Switch Settings:
Antenna Direction – This option sets the direction of travel for the antenna. This is normally set in the
“Normal” position. If during the tuning cycle, the antenna does not move in the proper direction,
change Dip SW-1 to the “Reversed” position.
Antenna Stall Current – For the Lil’ Tarheel, this option should be set to 200 MA. For Tarheel Models
100 – 400, use 900 MA. If the antenna changes direction in the middle of travel for no apparent
reason, try the 300 MA option for the Lil’ TH and 1000 Ma for the TH Models 100 – 400. For High
Sierra antennas with the Black Hawk motor set stall current to 900 MA.
SWR Threshold – Keep this in the Normal position unless the controller has trouble finding a match
on some bands. This option will allow the controller to accept a slightly higher SWR. With the option
set to “Alternate” the controller will still search and find the lowest SWR.
