[Elecraft] Possible issue with K3 Line In port?

[Paula Uscian]

 Thanks to the many people who responded to my post, it is much appreciated. I was thinking Joe's recommendation below was my last option. But then a strange thing happened.
In doing some last checks before exploratory surgery on the K3's IO board, I decided to unplug the Phones jack of my Radiosport headset from the front of the rig and plug it into the phones jack on the TASCAM to confirm that I was hearing tones on TX. I did hear the tones (as I had before with the phones plugged into the K3 and listening via the K3 monitor). But after I plugged the Radiosport phone plug back into the K3, voila -- I have a reading on the ALC meter.
Of perhaps greater significance, I verified operation is now fine by completing a Q on FT8.
I also now have TX for RTTY as well.
I'd like to think I'm home free due to clean living ;-), but fear I may have a dreaded intermittent issue. Time will tell.
Many tnx agn to all who responded, your comments were most helpful. For completeness of this thread, I've included responses to some of the recommendations and questions below.
73 Paula k9ir
1, VOX shouldn't be needed with FT8 using WSJT as it communicates with the K3 via CAT commands. FYI no difference with or without VOX. I have used VOX for RTTY AFSK in the past, but got disabused of that sin when I had some issues with WinWarbler that were resolved by running Commander.2. It is difficult for me to test a different cable as the TASCAM Line out consists of 2 RCA jacks. I happen to have a cable with 2 RCA plugs at one end and a 3.5mm plug at the other end, but I don't have another one to try (note to self -- get another cable just in case). However, I did run a totally different 3.5mm to 3.5mm cable from the Line Out (Green) port on the PC to the Line In port on the K3 and got the same failure (AFTER reconfiguring the software to look to the internal sound card for TX). Yes, it is possible I have 2 bad sound cards and 2 bad cables, but I'm playing the odds for next steps ;-).3. I have been using the meter selection that shows ALC during these tests.4. I do hear tones -- a steady tone when I click the Tune button and modulating tones when I click the TX button, in WSJT -- in my headset, so I think the TASCAM Line Out is working.I just see no bars on the ALC display.
I also checked to make sure recent Windows 10 updates didn't alter my Privacy settings for the microphone; those permissions remain the same as when the system was working.
    On Monday, June 24, 2019, 08:40:09 AM CDT, Joe Subich, W4TV <lists at subich.com> wrote:  
 
 
Check L4 and L5 on the KIO3 Audio Input board.  They are in series with
the Line IN audio and return lines and have been known to open.  The
quick fix is to simply bypass them with jumpers.

73,

    ... Joe, W4TV


On 2019-06-24 9:29 AM, Paula Uscian wrote:
> I suspect I may have an issue with the Line In port of my K3, as my ability to TX in any digital mode has gone away.
> 
> Setup:
> 1. Using a Tascam US-122 MKII outboard sound card.
> 2. MIC SEL is set to Line In on the K3.
> 3. Digital software, e.g., WinWarbler and WSJT, have the Tascam selected for TX and RX.
> 4. Mode selection for FT8 is set to Data, for RTTY is set to AFSK 45 bps.
> 5. Levels are the same as when this system worked – K3 Mic level is set around 43-44.
> 
> Symptoms:
> 1. When I try to TX on FT8 from within WSJT, the K3 red TX light comes on and over my headphones I can hear a steady tuning tone, but I have no power out, not one bar.
> 2. During TX I do hear “behind” the tones a brief low level buzzy/crackly sound that recurs every second or so.
> 3. I get the same results as above when trying to TX in WSJT, though I hear tones typical of a transmission vs. a steady tone.
> 4. I get the same results as above when I switch to RTTY and TX within WinWarbler; RYRYRY, but no power out.
> 5. The Tascam and WSJT work fine together to decode FT8 signals.
> 
> T-shooting Steps to Date:
> 1. Uninstalled, rebooted and reinstalled all Tascam software and current drivers. Same results.
> 2. Tried the Line Out from the internal PC soundcard to the Line In on the K3. This also involved using a different cable from that connecting the Tascam to the K3. Reconfigured the digital software to use the internal sound card for TX. Same results as described above (including the noise).
> 3. Verified the K3 does TX (at least on CW).
> 
> I suspect the board with the Line In port may have gone bad, but not sure if that’s the issue. If so, is there anything further worth checking or should I just replace the board?
> 
> Thanks for any guidance!
> 
> 73 Paula k9ir
> 
> Sent from Mail for Windows 10
> 
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