ND2E's Blog

Well, it isn’t a bad soundcard-just needed to reinstall the software. So now I have to make a decision…do I reinstall the audio lashup to get back on the air or do I wait for the Signalink USB to arrive before I set things up again?

The other day I was in a QSO when the other operator mentioned seeing what he called hum bars on my transmission. It seemed stranged at the time but I did back off on the Tx audio a bit and he said it was better.

A couple of days later I was trying to work to the North East and the FT-857 would not key. (I was running digital VOX.) Knowing that I had not changed the Tx Audio levels since the previous session, I started testing. The radio would key when I changed the PTT logic to the CAT but it was extremely insensitive when set to digital VOX. That seemed a bit strange so I pulled the Tx audio connector and plugged in my headset. What to my wondering ears did appear but a harsh low pitched growl when I started to transmit.

I switched DM780 to the internal soundcard to verify that it was a soundcard problem not a computer problem. It was the external soundcard so I am now off the air waiting for my new Signalink USB to arrive.Hopefully it will be here Thursday of Friday so I can get back on the air this weekend.

Late last summer when I was having computer and radio problems, a station in South Carolina mentioned that I was driving the Tx audio a bit hard because he could see distortion on the waterfall. There was a noticeable but faint set of tracks … not nearly as bad as some of the Cuban stations but still noticeable. At that time I dialed back on the audio going to the TS-2000 and he said it cleared up – Mostly. At that time I did not recognize a sound card problem…I monitored the audio with my headset but did not notice any distortion. I my mind the external soundcard I have used for several years was degraded and continuing to fail but I did not notice it.

So now I wonder how is the best way to actually monitor the output signal of the soundcard – really, how to monitor the IMD of the radio/souncard combo. I am open to suggestions, not all Digital Mode software supports IMD measurement and in most instances it really is only a measure of the Rx audio path from the receiver to the waterfall and is subject to significant overdrive in the audio and DSP chain.

If anyone has a good recommendation – I am willing to try it.

73 de ND2E/Joe

It has been interesting working on the Gx270. In a previous post I noted that the computer was running a bit slow so I ran a series of diagnostics and when I was though the machine ran so slow that it took 20-30 minutes to boot. I spent several 10s of hours trying to figure out what I did. I ran into brick walls at every turn. Google was not my friend. It didn’t take me to anything that was helpful.

I started looking for a new motherboard to replace what I had. I noticed that in one ad for a used motherboard, that the copy said that it had adjustable speed using the “compatibility mode.” Researching compatibility mode, I found that it was a checkoff in the BIOS. Looking at my BIOS I saw that Compatibility was enabled. I turned it off and rebooted and the machine came back to life at the original speed. I was Back in business.

The improvement brought me back to the same point that I had been in several weeks before — the beast was slower and I was using nearly 100% realtime when I used HRD v5. Beta. Now the 5 Beta is not supposed to load the machine badly so I knew that something else was the cause.

I run an external USB soundcard, just because I had a 24 bit external left over from the days when I was running a HP laptop that couldn’t seem to run the PSK software I was using when linked to the internal soundcard. Working may way trough the various options for the soundcard I found that the “monitor” check off was enabled. Unchecking that bit decreased the realtime usage down to a reasonable level <6% before starting HRD.

However when I start HRD, realtime goes to nearly 50%…so something else is in play. I noticed that HRD itself was only using about 10% realtime but my system had jumped considerably. I am still working on that issue and will document it as soon as I figure it out.

Well it has been a while since I have had a chance to write anything about the activities at ND2E or its household. We have had a bit of snow here…about 6 or 7 inches according to the pile of white stuff on the deck. In any case I have been forced to use the old Dell Latitude laptop for the psk computer because I’ve done something to the GX27o, it was running a bit slower than I thought it should so I decided to run diagnostics on it. THe only diagnostic disks I had were for the dimension 8400 but I figured they would run just fine on the GX270. Well they ran fine and it got a clean bill of health but when I went to reboot it took forever. So now I am trying to figure out what is wrong. It appears that the disk is in constant motion and the CPU is running and using 100% realtime.

I’ve googled everything I could think of about slow GX270s but haven’t seen anything that might help. So I am slowly replacing things and rebooting. There must be something I a missing, some clue that would shed some light on the problem.