144-MHz 1200W Power Amp

March, 2019: I purchased a partially constructed 2m W6PQL 1200 watt LDMOS amplifier kit Spring of 2018. In test I got 800-900w output with 1.75w drive which was below the expected 1000w. In attempting to discover where the problem lay I caused an arc which vaporized a trace in the output pc booard. Repair by using buss wire did not fix it. So I decided to purchase the 1500w pallet from W6PQL fully assembled vs repair. In testing the new amp I discovered that my 2500B Bird element reads 1-dB low at 144-MHz so that 900w reading would actually have been 1133w which is close to the 1200w maximum rating of the original amplifier. I will replace the output pc board and use new caps vs trying to reuse the existing capacitors. The coax lines will be reused. After re-build and testing the 1200w pallet will be offered for sale along with FET switch ($20) and input 10-dB attenuator board ($35). A new assembled 1200w pallet costs $725 from W6PQL. I will offer the re-built pallet with accessories for 70% of new cost. I recomment purchasing the pre-drilled/tapped heat sink ($90.00) directly from W6PQL, for ease of mounting the 1200w pallet and avoiding extra shipping costs. Tests results

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