[Amps] Slow start-up of Amps on CW

Mark Bitterlich markbitterlich at embarqmail.com
Tue Mar 12 21:09:30 EDT 2024


FWIW, I've seen the same on two FTdx-9000MP's. Very apparent with ANY ALC deflection and running an amplifier. De wa3jpy Mark
-------- Original message --------From: Jim Brown <jim at audiosystemsgroup.com> Date: 3/12/24  3:30 PM  (GMT-05:00) To: amps at contesting.com Subject: Re: [Amps] Slow start-up of Amps on CW On 3/12/2024 12:07 PM, Steve Harrison wrote:> I would definitely consider FT-991As,Yaesu radios have long had problems with bandwidth on both CW and SSB, producing clicks and splatter that are much wider than rigs from Kenwood, Elecraft, and Flex. See this link, which is my analysis of ARRL Labs data of popular rigs on CW. It was done with their blessing -- they sent me the electronic output of their measurements.http://k9yc.com/TXNoise.pdfIn following years, I've traced SSB signals with wildly excessive splatter to Yaesu rigs. Splatter extends 2.5 kHz on both sides of the signal (that is, in the suppressed sideband, and on the other side of the active sideband) only 20 dB. W4TV traced the cause to the way Yaesu is doing signal processing in the transmit chain, and there are no user adjustments to fix it.This can be heard any time with ragchewers in the SSB bands, and clearly seen on good spectrum and waterfall displays that can get narrow, like the Elecraft P3. Clean signals show up on the waterfall as vertical bars with bandwidth of 2.5-2.8 kHz; these dirty signals show horizontal shoots from both sides of the bar on voice peaks.73, Jim K9YC_______________________________________________Amps mailing listAmps at contesting.comhttp://lists.contesting.com/mailman/listinfo/amps


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