Note
The Palstar AT5K is an American-made, high-power antenna tuner designed to provide adjustable impedance matching for both balanced and unbalanced outputs. It utilizes a T-matching network to optimize the performance of transmitters and antennas across the HF spectrum.
Features
– Two 600 pF capacitors rated at 6 kV, featuring 6:1 Vernier drives for precision tuning.
– A 28 μH roller inductor wound with #10 wire on a steatite ceramic core, featuring a silver-plated bar and wheel.
– A 1:1 current-type ferrite balun located at the input.
– A 6-position antenna selector switch with wafers rated for 7 kV/10A.
– Metering: A dual-movement cross-needle meter that displays forward and reflected power simultaneously, with SWR indicated at the needle intersection. Essentially a built-in Palstar PM2000A.
– Forced air cooling
Specifications
– Frequency Coverage: 1.8 to 29.5 MHz.
– Power Maximum: 5000 W PEP SSB or 3500 W single tone.
– Power Rating: 3500 W single tone, low loss, wide Z range.
– Frequency Range: 160m to 15m, with a limited Z range on 10m.
– Switch Rating: Switch wafers are rated for 7 kV and 10 A.
– Power Range Switch: Two-position switch for 300 W or 3000 W.
– Impedance Range: 10 to 2000 Ω from 160m to 10m, assuming a resistive load.
– Balanced Output: 1:1 current-type ferrite balun at the input.
Power Input: A 12 VDC input (2.1mm center positive) used to power the meter lamp, cooling fan, and peak metering circuits.
Power Specifications by Impedance
The following power ratings assume a single-tone, key-down operation:
Antenna Impedance Maximum Power Rating
80 – 150 Ω 1000 watts (all bands)
15 – 25 Ω 1500 watts (all bands)
250 – 500 Ω 3500 watts (all bands)
500 – 2000 Ω
3500 watts (160m)
3500 watts (80m–15m)
1500 watts (10m)
