Thanks, Tim, for the quick reply:

Here is the result of the recommended changes:

> 1.) Look in the Setup->General->Options tab and make
> sure that the Enable TX Out Delay check box is not checked.

It was checked, and I unchecked it.

> 2,) Use the smallest audio buffers that do not distort the
> audio (Setup->Audio->Primary).  I would start
> with 512.

It seems to receive fine even at 128, so I used that value.

> 3.) Use smaller CW RX/TX DSP buffers
> (Setup->DSP->Options)

I set to 512.

> 4.) Change the CW Blanking Delay value
> (Setup->Transmit)

The minimum value appears to be 10; I tried increasing the value, doesn't 
appear to address my specific type of issue (by the way, I did notice some 
noise on rx/tx transition as well as in the transmitted envelope, along with 
the still unidentified off-frequency low-level carrier (a few hundred Hz away) 
in the transmit signal, but those are not my primary focus, as they don't 
fundamentally prevent usability in CW; the "hesitation" as others have called 
it, is a fundamental usability problem - a show-stopper.

In a nutshell, my test is to send a single "dit" from my external keyer (set to 
about 15 WPM now, pretty slow) and see if that "dit" survives on the air.

>From what I can tell, there is enough delay from when the "dit" begins at the 
>Flex-1500 key input jack until RF appears on the transmit path that there is 
>no way the first CW symbol could emerge unscathed. The first symbol is 
>incomplete, and it sounds like it may also be damaged in terms of waveform, 
>but I've not tried using an oscilloscope to see. I haven't tried to measure 
>it, but I'm guessing 50-150 mSec, but rather than delaying the whole transmit 
>stream, the whole setup isn't getting into transmit state quickly, and instead 
>the first symbol is dropped or grossly foreshortened. By the way, I've done 
>this test at a variety of break-in delays (generally I'm using about 100 mSec, 
>which should be a decent "semi-break-in" value given that I've pretty much 
>foresaken the prospect of getting QSK.)

So, what to do - wait some more? Basically is the flex1500 I ordered within a 
few weeks of when flexradio first accepted orders, delivered a few weeks after 
flexradio began shipment, and sitting on the shelf awaiting the integrated USB 
driver which ostensibly targets among other things CW operation, just destined 
to be a hangar queen? I can accept that it's not destined to be a QSK rig 
(toooooo bad, I really got used to that about 1972 when I got my ten-tec 
argonaut 505), but I can't accept that it's not destined to be a CW rig at all, 
using either internal iambic or external iambic keyer (I'm not going to limit 
myself to sending on a keyboard - if that's the case this rig is headed for 
writeoff-land). Based on off-reflector messages received so far since my post 
yesterday, my experience is not unique. Certainly flex beta testing would 
include a few host machines of different capability levels so that a 1.6 GHz 
Atom with 2 GB RAM running only XP and
 Powersdr 2.0.16 could be quickly identified as insufficient, if that's the 
issue?

So, back on the shelf awaiting update, unless there's any other configuration 
change I can try.

Thanks for the attempted assist,

Dave

--- On Sun, 11/21/10, Tim Ellison <[email protected]> wrote:

> From: Tim Ellison <[email protected]>
> Subject: RE: [FlexEdge] First CW transmit/QSO attempt with > Flex 1500
> To: "David Feldman" <[email protected]>, "[email protected]" 
> <[email protected]>
> Date: Sunday, November 21, 2010, 3:13 PM
> It does help.  Junk from a
> previous DB could have been getting in the way, but that
> does not seem to be the issue.
> 
> Here are a few things to check or fiddle with.
> 
> 1.) Look in the Setup->General->Options tab and make
> sure that the Enable TX Out Delay check box is not checked.
> 2,) Use the smallest audio buffers that do not distort the
> audio (Setup->Audio->Primary).  I would start
> with 512.
> 3.) Use smaller CW RX/TX DSP buffers
> (Setup->DSP->Options)
> 4.) Change the CW Blanking Delay value
> (Setup->Transmit)
> 
> I am not a CW op so I do not want to venture a guess at
> what settings to try, but these are the things that you can
> change which can improve latency.
> 
> -Tim
> 
> 
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]]
> On Behalf Of David Feldman
> Sent: Sunday, November 21, 2010 2:58 PM
> To: [email protected]
> Subject: Re: [FlexEdge] First CW transmit/QSO attempt with
> > Flex 1500
> 
> When I first started 2.0.16, I am pretty sure it created a
> new database, because I had uninstalled 2.0.5 prior to
> installing 2.0.16. In any event, I also tried resetting the
> database and restarting the program, and got the same
> results (the reset/restart left an XML file on the desktop
> which I didn't look at.)
> 
> Hope this is helpful info,
> 
> Dave
> 
> > Message: 7
> > Date: Sat, 20 Nov 2010 21:28:08 -0500
> > From: "Tim (W4TME)" <[email protected]>
> > To: [email protected]
> > Subject: Re: [FlexEdge] First CW transmit/QSO attempt
> with Flex 1500
> >     and 2.0.16 beta on 1.6 GHz Atom XP box
> > Message-ID: <[email protected]>
> > Content-Type: text/plain; charset=windows-1252;
> format=flowed
> > 
> > Did you import the database from 2.0.5 into 2.0.16?
> > 
> > -Tim
> > ---
> > W4TME
> > FlexRadio Systems Internet Systems Admin.
> > Product Verification Team
> > Tune In Excitement?
> > 
> > 
> > On 11/20/2010 6:54 PM, David Feldman wrote:
> > > This afternoon I had my first QSO with the Flex
> 1500
> > and PowerSDR 2.0.16 using an external keyer. I'm an
> absolute beginner 
> > with any flexradio product - I bought the rig long
> ago, received it 
> > when they began shipping, and put it on the shelf (as
> I'm exclusively 
> > CW op) until 2.0.16 beta was released. So, today is my
> first on-air 
> > experience with the rig. I was able to upgrade from
> 2.0.5 
> > (out-of-the-box CDROM) to 2.0.16 beta without any
> difficulty.
> > >
> > > Where I'm struggling: I notice a pronounced
> > "hesitation" effect with the first transmit symbol,
> and also hear a 
> > slightly off-frequency carrier (on another receiver in
> the shack) 
> > during transmit - a kind of "backwave" but not on the
> exact TX 
> > frequency. I don't think either of these is news to
> the developers or 
> > reflector, but I just wanted to see if I should be
> making any 
> > configuration/operational changes before putting rig
> back on shelf 
> > awaiting later software version. I did try adjusting
> CW TX buffer size 
> > between 256 and 2048 and didn't see much difference. I
> did find it 
> > necessary to run keyer's own sidetone (with "Disable
> Monitor" selected 
> > on powersdr) as powersdr sidetone is delayed enough vs
> actual sending, 
> > and powersdr sidetone audio level is dependent on
> transmit drive level 
> > (which means no powersdr sidetone when tx power turned
> down to 0 for 
> > testing.)
> > >
> > > To work around the first-symbol hesitation, I was
> able
> > to complete a QSO by setting the "break in delay"
> parameter to ~750 
> > mSec (so basically I could send a whole transmission
> without the rig 
> > dropping back into receive.) I tried a simple test of
> sending a string 
> > of dits at modest speed, and adjusted the Delay
> parameter down to 0 mS 
> > (QSK hoped for) and discovered the shack receiver was
> not hearing any 
> > useful signal (certainly not a string of dits). Until
> the delay was 
> > set long enough to keep the rig in transmit between
> dits, I could not 
> > obtain a workable transmit signal.
> > >
> > > The machine is an ATOM 1.6 GHz box with XP and
> is
> > doing nothing but running powersdr. CPU utilization
> seems to be 
> > 50-60%.
> > >
> > > I looked at the flexedge archives and 2.0.16
> release
> > notes and didn't see any advice that seems directed at
> the 
> > first-symbol hesitation which is my main concern.
> > >
> > > Thanks for any advice,
> > >
> > > 73 Dave WB0GAZ
> > 
> 
> 
>       
> 
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