maestro cw monitor distortion

Martin AA6E

I'm running Maestro and a 6500 on 1.7.32.15.  I find that the CW monitor note is rather distorted, using either the internal speaker or headphones.  It sounds like it's being clipped in an overloaded amplifier. Is this normal, or have I misadjusted something?  I do not find any Monitor level adjustment on Maestro, but I wish there was one.

k3Tim

https://community.flexradio.com/flexradio/topics/maestro-sidetone

To adjust the level of sidetone, in CW mode / Xmt enabled push the TX Menu knob and the ssidetone soft control is there.

Tim

Martin AA6E

By golly, you're right.  Just where the adjustment should be! Maestro is not idiot proof.  Where do I report that problem? ...

John G3WGV

I agree. The CW sidetone has a rather unpleasant sound, which is something of a surprise. I was planning to put the scope on it today to see what the waveform looks like but I suspect it is nearly a square wave.

73, John, G3WGV

John G3WGV

I played with this some more. On the scope the waveform is nearly sinusoidal with just small glitches around the zero crossing points which would probably be unnoticeable. However, it turns out that the sidetone actually comprises two tones - one at the intended pitch and another at a lower frequency, possibly one third of the fundamental. It is this that gives the sidetone its odd sound.

The effect is most pronounced if you select a high pitch, such as 1500Hz. Interestingly the lower tone changes in frequency as the sidetone pitch is varied, which makes me think that it is indeed a subharmonic.

The lower frequency tone is several dB down but is certainly enough to make the sidetone about T6, which is a tad disappointing for us CW aficionados.

Simon Lewis

KC2QMA_John

I bet it's the way the speaker resonates in the maestro’s plastic housing?

If there is a way to do an audio frequency sweep test that will help verify, There may be a particular frequency that is more noticeable. Also try to see if varying the tone’s volume level has an effect on the distortion.

Just taking a guess?

John G3WGV

No, it's nothing to do with the loudspeaker - the same effect is apparent in headphones and it can be seen on the oscilloscope.

As I said in my original post, it is more noticeable with a higher pitch sidetone but that is almost certainly just because the lower tone's pitch is now well within normal hearing frequency range.

The level of both tones changes as the sidetone level is varied but the amplitude relationship remains the same. It's not really distortion at all - it's the two tones that makes it sound distorted.

73, John, 'WGV

John G3WGV

Let's hope so. It would be a shame if it's something in the hardware!

KC2QMA_John

That's good news! 

k3Tim

Hi John

Thanks for investigating this -  an interesting finding.

One could route (via cable) the output signal into a PC and use a program such as SpecLab to perform a frequency analysis of it (Spectrum Analyzer). 

_..--
 TiM

Keith Hamilton

I asked a tech about the strange sidetone on the Maestro at Dayton. He said it is a known bug and will be fixed.

K1UO Larry

Martin..  Its already reported.  See the link Tim posted above.

Steve (N9SKM)

Posted 6 min ago

Gerald - K5SDR, Official Rep

• 460 Posts
• 703 Reply Likes

Lew, I just spoke with the engineers this afternoon and they have already fixed the CW sidetone issue.  It will be alpha test by the weekend and will be in the next release.  We are planning shorter release cycles to get public updates out more quickly.

Tim - W4TME

John, I have added you analysis to our bug report.  Thank you.

Tim - W4TME

This is not the same problem that Gerald referred to.

Tim - W4TME

This problem report was previously entered into our bug tracker as defect #2914.

W3PH

I couldn't find it either until I read this message.  I searched the PDF manual and saw the menu but it wasn't obvious where it was hidden.

W3PH

It really is ratty, and I was surprised too.  My first impulse, having just received my Maestro yesterday & still having the shipping box, was to send it back.  2nd day:  I see that this is on the fix list so there's hope.  I'm a little surprised after a year in development to see this kind of CW glitch, but I guess we have to accept that CW isn't the priority that it once was.  SIgh.  

W3PH

Speaking of the speaker, I wasn't expecting much since it's small, but it's quite good, both for phone & CW.  I've been listening to it all afternoon while I work from home on my dining room table.  The CW sidetone, not at all good, but the speaker isn't the problem.

Gerald-K5SDR

CW is always a priority with us.  This is one of the artifacts of using the K1EL keyer chip to directly key side tone.  We have it on the list to move the side tone synthesis into DSP software on the Maestro display unit.  

John - AF3K

I'm running Maestro v1.10.16.25 and this problem seems to still be outstanding.  

The workaround for now is to just plug the key into the 6000 directly since in my shack the 6000 and Maestro sit on the same desk 99% of the time.

Is there any progress on fixing this? It seems the priority should go up with the release of V2 as there will be no workaround for the remote WAN case.

Tim - W4TME

John, here is the "skinny" on this issue.  The distortion is a product of the component values and tolerances used in the monitor circuit. It isn't a simple matter of changing the components because if it was, it would have been done already.

We think there may be a possible software fix that can be applied that would clean up the waveform.  In software development parlance, this would be a "science project", meaning we would have to vet out several ideas before we know if it is possible to do or not.  We have this on our list to address.  Unfortunately I do not have a possible timeframe for when we might get started working on the science project.

John - AF3K

Tim, Thanks for sharing the "skinny". Much appreciated. Good luck with the science project.

John AF3K

John

July 2018...So, what is status of bug tracker as defect #2914 Maestro CW monitor distortion fix?

Charlie_KB8CR

That's what I'm wondering (before I buy a Maestro).

John

I like my Maestro, but the internal CW monitor is really annoying. I mean REALLY bad. No one has responded to my post, other than you, so I don't know if the problem has been fixed.
One could work around this by using an external keyer, but since I use headphones, this work around would not work for me.
See if you can get a straight answer out of the folks at Flex before you buy one. And please let me know what they say, if you would.

Charlie_KB8CR

I hear ya, John. I've seen a video of the sidetone and wow is that raspy. For the moment, I'm using my RemoteRig boxes for remote CW operation. I already had them from using my IC7100 remotely, and they work perfectly, but it's more hardware to tote around when I travel.  I'm really surprised that they haven't fixed that in 2 years of posts I've read. One of the main reasons I got the 6400 was its remote capability. Don't get me wrong, I LOVE the radio, but was hoping they'd have a remote paddle capability for laptops by now (even if it's a small hardware extra), and while you can use paddles with the Maestro, that sidetone is really disappointing. I've tried CWX, but I guess I'm a paddle kind of guy. The Swedes that built the RemoteRig boxes can't be that much smarter than Flex can they? hi hi. If I hear something I'll let ya know. Til then, that money will stay in my wallet. 

Martin AA6E

I agree this is significant problem, even though I don't use the Maestro often for CW. I have found a weird workaround. You can tweak the side tone frequency to "tune out" the harsh tones. Might help.

John

Hi Martin,

Like many aging CW ops I like my sidetone around 600 Hz. Nevertheless, I will tweak the frequency as you suggest and see what happens.

The most surprising part to me is that Flex would even ship the Maestro product with this significant problem. It is as if no one at Flex was thinking of the CW operator using Maestro. Other than this issue, I have been very happy with my 6500. Wish I could use the Maestro though on CW.

If it has been 2 years without a fix, then shame on Flex. Even Yaesu will fix my FTdx5000 OLED issues for free, and my FTdx5000 is about 6 years old (with a lovely CW monitor note)!

Thanks for the suggestion.

Vy 73, John  W3NA