Hello Eric There's no doubt that a KPA1500 physical installation needs some careful attention to the noise aspect. That said, I'm a bit surprised by your problem with the PSU fan. I can certainly hear mine but, overall, the noise is entirely dominated by the RF deck fans. I've located the PSU under my operating desk, which is made of a dense particleboard material. The RF deck sits alongside my TS-890S transceiver on the desk. I can hear the PSU fan if I put my head below desk level but, even then, I don't find the fan to be particularly high-pitched in its acoustic output. Could you possibly have a faulty fan (maybe excess nearing noise)?
On the other hand, I do find the RF deck fans test my patience a bit, especially since the last round of major firmware updates which start the cooling at a lower heatsink temperature. That probably works well in a high-output environment, where it no doubt delays the onset of heat soaking. But when the amplifier "loafs" in a low power, low duty cycle environment as it does in some of my applications. it just starts the noise prematurely. It'd be great to see something like an "80m rag-chew" option for those times! 73, Peter (VK6HP). -----Original Message----- From: [email protected] <[email protected]> On Behalf Of eric norris via Elecraft Sent: Tuesday, 11 June 2019 7:57 AM To: [email protected]; [email protected]; Elecraft Reflector <[email protected]> Subject: [Elecraft] KPA1500 Power Supply Fan Noise More broadly, has there been any progress on reducing the piercing power supply fan noise on the KPA1500 when only using it as a tuner or an antenna switch? I complained about this a year ago, and I find it completely unacceptable. No set of noise-reducing headphones that I have tried works well enough to make the noise tolerable. I've tried moving the PS deck around with minimal improvement. This just doesn't seem to fit Elecraft's philosophy of a quiet operating environment. Why do these fans have to operate at full throttle when there is minimal current draw from the rf deck? Why do these fans create such a piercing high-pitched note? If there is no response from Elecraft, what have other ops done--short of moving the PS into an adjoining room--to mitigate the scream? Thanks, 73 Eric WD6DBM Sent from Yahoo Mail on Android ______________________________________________________________ Elecraft mailing list Home: http://secure-web.cisco.com/1tDsvUQJ_0zB23ghHb5KaAdzs0lJaKMogNen4iI_PDswSPolixJJ3iMrhUoFvfGgoxzbs0DGdGSSJL9x3VyZATgBP4zclJcBHotmk4r96__2YQRTeAi6FCpWxXILQqJ_IxPGZP8io4Yy2gzRdGerK7srzNw90BfE_ZOAFkDwLUzXowtU4dDgAziktXM2CaF_pmpCeXLxJMFjA6FB5k-74EYEqFaZkzaoXClH4rDm6FUv8b4ZNQGrysSjhXPwBuTRHw19PiQDvbA8aslrCqhIoTpUDEqhWyCBPw6pdw7_6qf-3cJoI6RgsgqLVHJhpZrhjT4EJ_rhWSPHF7dkhVbZQFcqVIrSZP2cIvpbhns4oqu5yxQUlH-vLCJf6b3seCrDPHKM12n7oEwMzs5agfcomTpSv2qGLxI-g2jcswmHrXHnp9W52FpbNKXl6CW2lRdQCpkMg0-jSAQ99VrIWXI1Pu0ICX96UOyhS7gYoOxWpTEE/http%3A%2F%2Fmailman.qth.net%2Fmailman%2Flistinfo%2Felecraft Help: http://secure-web.cisco.com/12HNFcbTeFZTbPNpVwVrvnNNKUwoEGeZbNguWyUO1MGEuYV1WffC05TQWFNvX_wofLrLQM8T9KGmWEbr6APGXL7hEv9QfXImhYsMuKFrSQT-4GhmdWzvoxUCdcgGzaV4-7k-CnR1GodVheHO9M8D8MGZLxCZUL59s6-YsOFQleipckCk-1b-u4D0nu-Xnu9n9YDG5S9cf_LDmhDy5KEa3vCSYVij75lBjaXEmkq_EoUImkfEcvrX7MV4YFAqZ4h9oEzkpbzyB5k3pNRZsmffdEXeqVHAKGeDBtVdNKW05kMwvQI0HOtn6mkoaD_uttVjsnl_OVXFD7bzu12kZJRZlW-zxLtJpmLx_W9UURVGhB6S6WJWQWKIyA-NYqaXE6S9eFTfST_SP7R927FpbqaSlMcIhL2JOOsL98pRpeB-dE9gWP0BBZiB4yYLTnMq1-IYzrlMmZnf_-pnyFMX9DE-taVpjMaR4FWlvPnVuhT6vmFE/http%3A%2F%2Fmailman.qth.net%2Fmmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
