![]() BT1500A tuners feature two tandem mounted, precision ceramic roller inductors for a truly balanced tuner. Palstar BT1500A 1500 Watt Double L Balanced Antenna Tuners are the only 1,500 watt, double-L network antenna tuners on the market today. ![]() Palstar BT1500A 1500 Watt Double L Balanced Antenna Tuners True active peak reading lighted cross-needle SWR/Wattmeter allow you to read SWR, true peak or average forward and reflected power all at a glance on 300/3000 Watt ranges.Īre you running QRO? Consider one of these MFJ 976 Legal Limit Balanced Line Tuners from DX Engineering. MFJ 976 1500 Watt antenna tuners have a heavy duty 1:1 current balun that gives you superb balance and stays cool even at 1.5 kW. You'll also have excellent 10 meter performance because of MFJ's low minimum capacitance, exclusive Self-Resonance Killer™, and high-Q AirCore™ roller inductor with silver plated contacts. Four separate 500 pF capacitors in two gangs contribute a total of 2000 pF for highly efficient low loss separation on 160 meters. There's no complicated switching between high and low impedance and switching in additional capacitance or L-networks. MFJ's wide-range T-network delivers simple, fast, three-knob tuning. MFJ 976 tuners also tune random wires and coax-fed antennas. They tune any balanced lines including 600 ohm open wire line, 450/300 ohm ladder lines, 300/72 ohm twin lead, shielded or unshielded. These tuners provide superb balance, very wide matching ranges (12-2000 ohms) and continuous 1.8-30 MHz coverage including all WARC bands! They handle a full 1500 Watts SSB and CW. Remember the reason why you have a balanced feed line - low loss at high SWR on the line - the tuner is there just to make a proper presentation to your amp or transceiver and not to lower the SWR on the balanced line.MFJ 976 Legal Limit Balanced Line Tuners are 1500 Watt fully balanced antenna tuners. From my experience this is the best low loss practice for multiband operation. This can be accomplished by leaving slack in the feed line between the antenna and the balun either inside or outside the shack. The best way to address a balanced to unbalanced conversion is to stick with a good 1:1 current balun that is well overrated for your power level (a DX Engineering 10 KW 1:1 current balun is what I use) and then vary the length of the balanced feed line by a number of feet until the HF Auto tuner can make a match on all the bands of interest. ![]() Higher ratio baluns generally have higher losses as well. Adding a fixed ratio balun is a real roll of the dice. The actual impedance at the end of the balanced line can vary from a few ohms to many thousands and depends on your antenna, the frequency of operation and the length of feed line. If you are only planning on low power, I do have the original 4:1 balun from Palstar, and would be happy to negotiate a price.Ī 450 ohm or 600 ohm balanced feed line does not present a "clean" or mathematically correct 450 or 600 ohm impedance at the transmitter end of the feed line. Of note, I have a G5RV flat top (102’) with 450 ohm ladder line coming down from the center of the dipole to my shack. The tuner tunes flawlessly, and the balun takes absolutely everything I throw at it! At full legal power, I have not had any problems whatsoever. My final solution was a 6-8 foot length of RG-8 style coax (Wireman #106) from the tuner to a DX Engineering BAL200-H11-CT (which they recommend for use with tuners) that is rated 10 kW continuous/10 kW+ intermittent. I saturated (or is it desaturated?) the core several times during contest times. Unfortunately, this was one of their earlier ones, one in a plastic case. They traded it out for a 4:1 balun, which worked. Palstar initially suggested a 1:1 balun which did not work for me. When I upgraded to the HF-Auto, I needed to find a solution for my open wire line. The AT-Auto had a 4:1 balun toroid standard within the unit.
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