You do know that Graham works for Flex, don't you? 73
-----Original Message----- From: FlexRadio [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Jerry Sent: Friday, October 18, 2013 7:25 PM To: Steve Sterling; Flex-Radio E-Mail Reflector Subject: Re: [Flexradio] Flex-1500 Overdriving in Some Bands Well said Steve. I don't think anyone at Flex is paying any attention to the post any more On 10/18/2013 7:01 PM, Steve Sterling wrote: > When I set up my Flex on psk31, etc. there was a writeup on the > knowledge base or wiki on how to set up for digital modes. Key point > was that you left the "drive" at 100% and LOWERED the VAC to no more > than -6db, never as high as 0db. As explained, 0 db on the ALC was > where the digital audio chain flat-topped which creates copious > amounts of IMD. If you set at 0db ALC, you will distort because it has > no more headroom if it goes +0.1db. You won't see it on the screen > meter (insufficient significant digits) but others will hear it. > > Also, mic gain, equalizers and other tools in the microphone audio > chain are not in the VAC audio chain. Only the limiters and ALC. > Straight through. > > Oh, one area I also had problem with IMD. Your psk31 app and the FLEX > VAC input should be set at the same bit width and data rate. Otherwise > your 3rd party virtual audio cable software must convert from one > format to another, introducing distortion, instead of just passing the > bit stream unmodified. > > Set up right, Flex radios have a good reputation for being pretty > clean in the digital modes. > > Steve WA7DUH > > On 10/18/2013 10:59 AM, Mark Griffith wrote: >> Well, obviously it means 100% power, or 5 watts on this Flex-1500. >> >> My concern is, why do I get splatter at 30% power on one band, and no >> splatter on other bands at 100% power? >> >> As for a reference, I'm not sure what you mean. I'm asking if other >> Flex-1500 owners have similar problems. >> >> >> Mark >> KD0QYN >> >> >> >> >> On Friday, October 18, 2013 8:59 AM, Graham Haddock >> <gra...@flexradio.com> wrote: >> >> Mark: >> >> What do you think 100 percent of power means on PSK-31? >> >> >> What is the reference for the tests you are running? >> >> --- Graham / KE9H >> >> == >> >> >> >> >> On Fri, Oct 18, 2013 at 7:08 AM, Mark Griffith >> <mdgriffith2...@yahoo.com> wrote: >> >> Recently, I was working PSK31 on my Flex-1500 with other stations, >> and someone came on >>> my frequency and announced in a not very nice way that was I a lid >>> and splattering all over the band. I had not had any comments from >>> anyone I had worked before, so I was a little concerned if he was >>> right. So, I bought the PSKMETER kit and assembled it. After >>> running it and testing my signal, sure enough, I was splattering >>> quite a bit. This surprised me as I set my sound levels using the >>> ALC meter was always 0db or less and yielded full output power. >>> >>> To better get an idea of what was going on, I setup the SDR 2.6.4 >>> two-tone test to output two tones, 31hz apart, like 1000hz and 969hz >>> to simulate the PSK31 signal. Using PSKMETER and a dummy load to >>> limit stray RF signals, I tested on common PSK frequencies on all >>> the bands. All tests were done with no VACs enabled, and just using >>> the internal two-tone test so over driving by another software >>> program was eliminated. >>> >>> Here's what I found: >>> >>> 80m Starts over driving above 40% power >>> 40m Starts over driving above 30% power >>> 30m Starts over driving above 65% power >>> 20m Starts over driving above 85% power >>> 17m Starts over driving above 75% power >>> 15m No over driving at up to 100% power >>> 12m No over driving at up to 100% power >>> 10m Starts over driving above 35% power >>> 6m No over driving at up to 100% power >>> >>> In all cases, the meter for EQ, Mic, Leveler, Lev Gain, ALC, etc >>> never was any other value than zero. >>> >>> I have tried to work with FlexRadio support, and they gave me the >>> run-a-round, saying to try this or that....even to try using the >>> transmit filter to limit the bandwidth I am transmitting to >>> eliminate the splatter. I would like it if they just admit that the >>> hardware is causing the problem, but I have not received any answer >>> to that question. >>> >>> I had the TX/RX board replaced last summer because of an unfortunate >>> lightening strike. I'm wondering if this board is suspect, but they >>> won't answer. >>> >>> Has anyone else seen this issue of over driving on some frequencies >>> with the 1500? >>> >>> Lucky for me I use JT65 and JT9 modes most of the time now, and they >>> are far less susceptible to splatter than PSK, and my QSOs seem to >>> bear out that my 5 watt Flex-1500 and SkyWire antenna work pretty >>> well. I recently made two contacts from Missouri to Western >>> Australia, one on 20 meters and the other on 40 meters, a distance >>> of over 10,000 miles. >>> >>> >>> Mark >>> KD0QYN >>> _______________________________________________ >>> FlexRadio Systems Mailing List >>> FlexRadio@flex-radio.biz >>> http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz >>> Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ >>> Knowledge Base: http://kc.flexradio.com/ Homepage: >>> http://www.flexradio.com/ >>> >> _______________________________________________ >> FlexRadio Systems Mailing List >> FlexRadio@flex-radio.biz >> http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz >> Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ >> Knowledge Base: http://kc.flexradio.com/ Homepage: >> http://www.flexradio.com/ > > > _______________________________________________ > FlexRadio Systems Mailing List > FlexRadio@flex-radio.biz > http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz > Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ > Knowledge Base: http://kc.flexradio.com/ Homepage: > http://www.flexradio.com/ > _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
