This dummy load seems to be very well made and it is very light too! I needed something smaller than those heavy oil-filled loads made by Bird.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgfPaX0TnvWY5PQtjP_-p0p2yifxSfHvSibip_k0px01aW-NPT4F0IWWHBAqVi8mQquJhBizuFmodO88n3f1ozZdJreo0J_9N01dQLYtRd-WrGbJMieaNTnGgt8teIbcv9507J2T5qsNJI/s400/palstar_dummy1.jpg)
There is a metal hyperbolic cone around the ceramic resistor. The cone is mounted on aluminum stand-offs and it is used to correct the reactance component of the impedance at higher frequencies (especially on 6 meter). The enclosure is made from perforated anodized aluminum sheet. The RF connector is of silver/teflon type. The resistive element is held in place by two stainless steel clamps.
My MFJ-259B shows resistance of 52 ohms and reactance of X = 4 ohms for SWR 1.1:1 at 54 Mhz. At 14 Mhz the reactance drops to 2 ohms and R is exactly 53 ohms. Considering that the MFJ259B is not the most accurate instrument in the world - it should be just OK. This load is rated up to 500 Mhz but I am planing use it only on HF. I think the real characteristics are even better than what 259B shows! I'll take more accurate measurements with my Telepost LP-100 soon. At first glance DL1500 seems to be an excellent product and I am happy with it. A note of caution - this dummy load can take 1.5 kW power but only for up to 10 seconds and 100W for up to 10 minutes! Modifying the load for forced air cooling (installing a fan or two) will improve these numbers but breaks must be made between the intervals of high-power usage!
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