Thanks, Dave!
________________________________ From: Dave Beumer WØDHB <d...@w0dhb.net> To: 'Ed Wilson' <ed.wil...@ymail.com>; 'Tim Ellison' <t.m.ellison...@gmail.com>; flexra...@yahoogroups.com; w6...@w6cqz.org Cc: Flexradio@flex-radio.biz Sent: Thursday, October 20, 2011 5:30 PM Subject: RE: [Flexradio] VAC and JT65-HF Ed Using a transmit profile with a 250Hz wide filter centered at 1500 will help . Davt From:Ed Wilson [mailto:ed.wil...@ymail.com] Sent: Thursday, October 20, 2011 3:21 PM To: Tim Ellison; flexra...@yahoogroups.com; w6...@w6cqz.org Cc: Dave Beumer WØDHB; Flexradio@flex-radio.biz Subject: Re: [Flexradio] VAC and JT65-HF Thanks for the info, Tim. Maybe I am being too conservative with the -3 dB on the ALC, but I do not want to put out some of the "garbage" that I sometimes see when listening to JT-65 signals. A setting on the VAC TX gain of -1 dB would not put out anything close to 100 watts on my rigs, so apparently it a characteristic of JT65-HF. I have copied Joe Large, developer of the program, for some input (no pun intended!). Ed, K0KC ________________________________ From:Tim Ellison <t.m.ellison...@gmail.com> To: flexra...@yahoogroups.com Cc: Ed Wilson <ed.wil...@ymail.com>; Dave Beumer WØDHB <d...@w0dhb.net>; "Flexradio@flex-radio.biz" <Flexradio@flex-radio.biz> Sent: Thursday, October 20, 2011 4:50 PM Subject: Re: [Flexradio] VAC and JT65-HF Your PA is fine. The amount of drive is dependent on the AF gain being fed from the digital mode program. If it is not putting out 0 dB, then a VAC TX gain setting of 0 dB will not produce very near 100 watts PEP with a tone. You ALWAYS want to use DIGx modes for digital mode operation because it bypasses all of the voice signal processing (EQ, compander, leveler) that can adversely effect the AF generated by the digital mode program. You also NEVER want to exceed 0 dB on ALC, as this is "clipping" the DSP and that is never good for digital modes. I never exceed -1 dB to allow for some headroom. With Fldigi, I get 90W out on PSK31 with the VAC TX Gain = 0 Tim Ellison On 10/20/2011 3:27 PM, Ed Wilson wrote: Dave, I can get 100 watts out in the tune mode (and CW when I use that mode). Ed, K0KC ________________________________ From: Dave Beumer WØDHB <d...@w0dhb.net> To: 'Ed Wilson' <ed.wil...@ymail.com>; Flexradio@flex-radio.biz; flexra...@yahoogroups.com Sent: Thursday, October 20, 2011 2:48 PM Subject: RE: [Flexradio] VAC and JT65-HF Ed When I get a chance later today I’ll see the max power I can get out of JT65 alc -3 drive slider 100 into a dummy load. Have you tested your max power out hitting “TUN” and running Drive to 100 ? Maybe your overall output power is low. Dave From:Ed Wilson [mailto:ed.wil...@ymail.com] Sent: Thursday, October 20, 2011 10:39 AM To: Dave Beumer WØDHB; Flexradio@flex-radio.biz; flexra...@yahoogroups.com Subject: Re: [Flexradio] VAC and JT65-HF Dave, Thanks for the hints. First of all, the dummy load does not make any difference compared to the antenna since the VSWR is essentially 1:1 with the antenna. I did try PSK31 using DM780 and I was able to obtain about 50 watts output with the ALC reading -3 dB...I believe that I moved the slider up to -3 to obtain this reading. My transmit filter is 0 to 3K, so I do not think that should be a problem. Ed, K0KC ________________________________ From:Dave Beumer WØDHB <d...@w0dhb.net> To: 'Ed Wilson' <ed.wil...@ymail.com>; Flexradio@flex-radio.biz; flexra...@yahoogroups.com Sent: Thursday, October 20, 2011 12:23 PM Subject: RE: [Flexradio] VAC and JT65-HF Ed Have you tried to get higher power with other digital modes ? I can get 60+ watts out on PSK with Drive at 100, ALC level of -3 with level slider -1 . Are you certain your xmit filter is not attenuating the output.. have you tested with a dummy load ? Dave -----Original Message----- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Ed Wilson Sent: Thursday, October 20, 2011 8:50 AM To: Flexradio@flex-radio.biz; flexra...@yahoogroups.com Subject: [Flexradio] VAC and JT65-HF Colleagues, I have been running JT65A using the JT65-HF software for the past month or so with good results (several hundred contacts with at least half DX). I have a Flex-5000 and I am running PowerSDR 2.2.3 under Windows 7/32. I have set my Drive control to 100 and have adjusted the VAC TX gain for an ALC reading of -3 dB (-6 on the slider control). With these settings I get from 25 to 30 watts out, depending upon the band. This power output is adequate for JT-65A, but what if I wanted to run more power? The only way that I can get my power output into the 100 watt range is to do so by increasing the VAC TX gain to a value of at least 0 and then the ALC is up to +3 dB, which probably would create splatter all over the slice of spectrum set aside for JT65A. Also, any other suggestions for DSP or other settings that would optimize J65A operation with PowerSDR would be appreciated. Thanks, Ed, K0KC _______________________________________________ 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/ [Non-text portions of this message have been removed] __._,_.___ Reply to sender | Reply to group | Reply via web post | Start a New Topic Messages in this topic (6) Recent Activity: · New Members6 Visit Your Group -------- Any and all comments and opinions stated here are those of the individual user and not FlexRadio Systems MARKETPLACE Stay on top of your group activity without leaving the page you're on - Get the Yahoo! Toolbar now. 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