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Antenna tuner L for antenne longwire
This small coupler allows the adaptation of a longwire antenna of twenty meters for use in QRP power less than 25 watts on the 7 MHz ban
post 12 Sep 2024
Antenna Transmatch tuner Links →
Antenna tuner 150 watts
A tunner witha balun T200-6 should give a better Q but the T200-2 was in stock and gave me sufficient tuning range, the capacitors are radio types and can be used up to 150 Watts
Z-Match Portable Antenna Tuner
I built the Z-Match in about 3-4 days using available parts. decided I wanted to use my Z-Match for 7-21 Mhz operation so I adjusted the coil L1 to give me that range
50 MHz 6 Meter Tuner Circuits
After matching my antenna to a 1.0:1 SWR I measured the capacitor settings: 77pF on the TX side and 36pF on the antenna side
A QRP Transmatch ATU
The inductor, the tricky thing in matching units with variable inductance. For the body I found an old pill container with a diameter of 4cm. The coil is then wound on this with 60 windings of 1mm enameled copper wire
Z-Match Antenna for high performance
For most applications, a capacity of 350 pF for C1 and 2x230 pF for C2 is sufficient, if you want to cover the bands 10-80 m, an extension for 160 m will be presented later
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A tunner witha balun T200-6 should give a better Q but the T200-2 was in stock and gave me sufficient tuning range, the capacitors are radio types and can be used up to 150 Watts
I built the Z-Match in about 3-4 days using available parts. decided I wanted to use my Z-Match for 7-21 Mhz operation so I adjusted the coil L1 to give me that range
After matching my antenna to a 1.0:1 SWR I measured the capacitor settings: 77pF on the TX side and 36pF on the antenna side
The inductor, the tricky thing in matching units with variable inductance. For the body I found an old pill container with a diameter of 4cm. The coil is then wound on this with 60 windings of 1mm enameled copper wire
For most applications, a capacity of 350 pF for C1 and 2x230 pF for C2 is sufficient, if you want to cover the bands 10-80 m, an extension for 160 m will be presented later
23cm Yagi Antenna building Finished antenna at 1275 MHz SWR under 1:1.5 at resonant frequency
50 MHz preamp Gain 26dB with the BFG135 Preamps for 144 and 430 MHz, for 50 MHz, the BFG135a is a cheap transistor and in my view rather strong. It is not easily damaged by static discharge or RF power. FG connection
30 Volt Computer Power Supply Stack A bonus was that i discovered that these did not need a standby load connected to the supply to keep them running just apply mains power and close the Start lead to ground