Temporarily out of Stock
Please check back soon for availability
Hendricks Deluxe Tenna Dipper Kit
Designed by Steve Weber, KD1JV
The Deluxe Tenna Dipper provides a simple means of determining the 50
ohm resonant frequency of an HF antenna or ATU (Antenna Tuning
Unit). The small size and battery operation makes the unit ideal for
use in the field. It's perfect for antenna experimenters that don't want to tie a bunch of
money up in the higher priced analyzers. It's even priced lower than most
swr bridges, and this tells you "where" you are resonant, not just that
it's matched, or not matched, like a simple swr bridge.
- Wide tuning range: ~3 MHz to ~30 MHz in two ranges
- Four digit digital display with display shift down to 100Hz
- Eliminates the need for a transmitter and SWR bridge when:
- Trimming length of resonate dipole, and portable vertical antennas
- QRM free adjusting of antenna tuners and antennas
- Quickly adjust short, portable vertical antennas, eg. PAC-12 &
Screwdriver antennas, etc.
- Current draw is approximately 50mA
- Weight w/batteries: .66 lbs./10.6 oz./ 300g
A voltage controlled R/C oscillator generates a 5 volt square wave signal. This signal drives a
resistive Wheatstone bridge. One leg of the bridge is the "unknown" resistance, the antenna. A
wide band step up transformer is connected across the bridge to detect the signal produced when
the bridge is unbalanced. This signal is farther amplified by a Darlington pair transistor amplifier.
A high brightness LED is used to visually indicate the current in the collector of the amplifier.
When the antenna impedance at the unknown leg of the bridge is equal to 50 ohms, the bridge is
in balance and the LED will go out. Hence the name for this device, the Tenna Dipper, as we dip
the brightness of the LED to find the 50 ohm match.
Supporting Files and Documents
Deluxe Tenna Dipper Assembly Manual (4/24 update)
Deluxe Tenna Dipper Decal Install)