There is a lot of chatter about this on the IC-7610 IOgroup, and multiple screenshots of the IC-7610 with and without DPD enabled are in the files section. Most of this testing has been done by Adam Farson VA7OJ. Although this was released in anticipation of the IC-PW2 amplifier, a question came up as to whether this would be of any use without an amplifier. A quote from Adam “Even in the stand-alone mode, DPD will linearise the 7610's SSB output signal, improving TX IMD performance by 20 - 30 dB. This makes for a cleaner signal and reduces the likelihood of adjacent-channel interference.” I’m sure this was in direct response to the Clean Signal Initiative. Bravo! As Bob F. noted, several contest stations would rather work in the opposite direction and be as wide as possible to give them an advantage. I don’t know how this will be addressed in the future. Interestingly, as some of the Yaesu rigs were touted as having key clicks, Yaesu responded by an upgraded firmware that has a minimal limit on CW rise time. Of course, that requires rig owner intervention. ‘73 de Jim N2ZZ Director – Roanoke Division Representing ARRL members in North Carolina, South Carolina, Virginia and West Virginia ARRL – the national association for Amateur Radio Facebook Page: ARRL Roanoke Division Website: www.arrl-roanoke.org<http://www.arrl-roanoke.org/> [Text, logo Description automatically generated] From: arrl-odv <arrl-odv-bounces@reflector.arrl.org> On Behalf Of Mike Ritz Sent: Monday, November 27, 2023 12:02 PM To: arrl-odv@reflector.arrl.org Subject: [arrl-odv:35362] Fwd: Icom "Dynamic Predistortion" Changes to IC-7610 Some positive news. (See below.) I’d like to think this is a result of ARRL’s CSI efforts! It does show that manufacturers are taking the effort seriously though, and that ARRL can make an impact in the technical space as a benefit for members. Lots of bad clicks and chirpy signals in the CW test last weekend, including one from EU that sounded like an old spark set! Hope everybody had a great Thanksgiving. 73; Mike W7VO Sent from my iPhone, utilizing a very tiny keyboard fed from very fat fingers Begin forwarded message: From: Mike Ritz <w7vo@comcast.net<mailto:w7vo@comcast.net>> Date: November 27, 2023 at 8:40:31 AM PST To: Alan Rovner <k7ar@comcast.net<mailto:k7ar@comcast.net>> Subject: Re: Icom "Dynamic Predistortion" Changes to IC-7610 Thanks, Al! Another ham sent me a note on this also. Icom is one of the JA manufacturers involved with the CSI. Ray Novak, N9JA is a committee member. I don’t know if this was a direct result of CSI, but I’d like to think so! This is exactly what we were hoping would happen. 73; Mike W7VO Sent from my iPhone, utilizing a very tiny keyboard fed from very fat fingers On Nov 27, 2023, at 8:14 AM, Alan Rovner <k7ar@comcast.net<mailto:k7ar@comcast.net>> wrote: Hi Mike I thought you might be interested this news as part of your Clean Signal Initiative. Icom has released new firmware for the IC-7610 that implements something called dynamic predistortion. As far as I can tell it generates a cleaner SSB signal when enabled. I'll include a photo below. While this is a good thing, it looks like it only works with their upcoming PW2 amplifier. There is ongoing discussion about whether non-Icom amps will be supported. Also this only applies to normal SSB voice signals. CW, RTTY, FT8 or other audio tone modes have no need for this feature. In order to use predistortion, you have to connect the 7610 to a dummy load and go through a calibration process for each band. In the photo below the blue graph represents energy without predistortiion and the pink graph shows a cleaner signal with predistortion. Notice the pink graph has less energy away from the center test tone. Thought you might be interested, 73, Al, K7AR <FLgMmPe5ca0PzGmI.png>
