Date   
Re: About outta spec signals... uBitxv4

 

Board No.303/1
Mic In = `100mV
Po = 10W at 7MHz audio drive constant for all bands. Power varies.

Using Narda 30Db atten + Narda adjustable in series.

Only 2 markers, 2nd marker at the NET highest peak.

10M is just under 40db, Rest are as expected.
Emacs!
Emacs!
Emacs!
Emacs!


At 09-08-18, you wrote:
It would be great if more people could run tests on their uBITX transceivers. We seem to have only a few people with spectrum analyzers running test on a small test case of boards. There must be more people with equipment that could run test on a larger sample of radios.

If it turns out there a significant number or transceivers that do meet spec, maybe we could try to figure out why those work. And I agree the margin that the uBITX is out of spec may be in the measurement "noise" figure.

If you look at the spectrum analyzer screenshots the harmonics do not decrease with frequency. Even with no filter the harmonics would decrease with increasing frequency. It would only take a small improvement for the uBITX to be in spec.

Tom, wb6b

Re: Harmonic performance - SSB vs CW

rcbuck@...
 

Jerry,

You are correct. I was looking at Mouser and failed to notice the price was for a qty 500 reel.

Ray,
AB7HE

Re: Good news, bad news

Tom, wb6b
 

Re: Good news, bad news

Tom, wb6b
 

I was googling around some more and it looks like some folks have hacked the DebugWire protocol to create a free Arduino command line debugger.

Tom, wb6b

Re: Help needed with KD8CEC memory manager

a.vision
 

That's exactly what I am getting  I can't understand why any help greatly appreciated thanks .



Sent from my Samsung Galaxy smartphone.

-------- Original message --------
From: Bill <allerthomes@...>
Date: 09/08/2018 04:24 (GMT+00:00)
To: BITX20@groups.io
Subject: Re: [BITX20] Help needed with KD8CEC memory manager

I have gone back to the Hamskey website and tried to follow the directions for the memory manager. My problem right now is that nothing happens when I click "read from ubitx", although I did get it to work at one time, and was able to create a back up file, which I can load into the manager. I have made some changes and hit write to..., after hitting encode. A green bar will slowly run across the screen untill finished. Each time it will show o successful. So it seems I cannot read or write from this program right now. Any thoughts?

BITX40: Qui peut m’aider ? Who can help me ?

f6cxo
 

Bonjour

 

Y at'il des OMs francophones sur la liste

J'ai acheté un BITX40 et je n'en suis pas satisfait, j'ai un tac tac pendant la rotation du bouton Fréquence qui est assez pénible.

Merci de me répondre en direct sur mon adresse : f6cxo@...

 

73 Gégé

 

Re: Harmonic performance - SSB vs CW

Ashhar Farhan
 

The three section 30 MHz filter can incorporate notches for the troublesome spurs and harmonics.

- f

On Thu, Aug 9, 2018 at 11:02 AM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
The PX1002 SAW filter (86.85mhz)  is available quantity 1 from Mouser.
At quantity 1 it costs $12, vs $6 at quantity 500.

The PX1004 (82.2mhz)  would work in the uBitx, as noted in post 51172
Cost is $6 at quantity 500, same price as the PX1002.
I don't see anybody selling the PX1004 at less than a full reel of 500.

Jerry


Jerry, KE7ER

On Wed, Aug 8, 2018 at 08:34 PM, <rcbuck@...> wrote:
PX1004 would also work at 1/2 the cost of the PX1002.


Re: Harmonic performance - SSB vs CW

Jerry Gaffke
 

The PX1002 SAW filter (86.85mhz)  is available quantity 1 from Mouser.
At quantity 1 it costs $12, vs $6 at quantity 500.

The PX1004 (82.2mhz)  would work in the uBitx, as noted in post 51172
Cost is $6 at quantity 500, same price as the PX1002.
I don't see anybody selling the PX1004 at less than a full reel of 500.

Jerry


Jerry, KE7ER


On Wed, Aug 8, 2018 at 08:34 PM, <rcbuck@...> wrote:
PX1004 would also work at 1/2 the cost of the PX1002.

Re: About outta spec signals...

Christopher Miller
 

Im going to paraphrase what I said directly to Allison as I didn't get a reply. The way I see it, the problem isn't really able to be noticed unless a person is generally in line of site of a transmitter (objects absorb rf and the emissions are also blocked).

She mentioned the aviation hf and marine bands were at risk.

Well here is the thing, the hf aviation bands are used when an aircraft flys trans ocean. So unless you are off the coast outside the realm of where the FCC can even do anything, as a pilot you are fine. If you are maritime, you are in the oceans or close where guess what the FCC has no rights.

So in the end if no one can detect the issue and the major players aren't under the control of the FCC... uh? Being marginal matters why?

Re: About outta spec signals...

Jerry Gaffke
 

OK, Allison says "We are talking greater than 10DB"
Better make that a 200W rig.


On Wed, Aug 8, 2018 at 08:52 PM, Jerry Gaffke wrote:

On present units it would be best to clean them up, though our power levels are low enough
that they may cause less bother than a 100W rig that does meet spec.

Re: Harmonic performance - SSB vs CW

Jerry Gaffke
 

I have gotten a part to just fall out.

Late 1970's I was working on a new memory mapped video graphics board
(a very very early CGA sort of thing driven by a Z80 that sold for $5000).
The 7489 RAM's used in the colormaps were dropping bits when they got hot.

Got some different ones, we installed those DIP16 parts into a board to test.
I played a heat gun on them to see if they would fail like the old ones.
Worked good, then suddenly, darn, they were failing again!
Looked away from the video screen to see I had melted the solder, the parts had
fallen to the floor.

Jerry



On Wed, Aug 8, 2018 at 07:49 PM, ajparent1/KB1GMX wrote:
Oh,  never ever got a part to just fall out even with the Pace.
Solder has enough surface tension to never get it all as a thin film
will hold a part well.  Either that or SMT parts have to be glued down.

Re: About outta spec signals...

ajparent1/KB1GMX <kb1gmx@...>
 

Gordon,

Glad to help.  I doubt anyone else has removed relays on one of these.
I've had to help friends do it because of suspected failed relay.  To not fry
the board its controlled heat and patience. 

Oddly its the third time hat picture was posted to day and I think this is the third thread.

Allison

Re: About outta spec signals...

Jerry Gaffke
 

The regs make it pretty clear, any harmonics or spurs that have more power than 43dB down from the carrier are out of spec.
If you measure exactly -43dB then get a more accurate instrument, I doubt it is exactly -43.0000000000000000000000dB.
I doubt *they* care about exactly, and exactly where *they* would care on a 10W rig I don't know.

If a manufacturer sells 10,000 units and 5 are out of spec, then those 5 are out of spec.
But some of the caps dried out in transit?  Those rigs are still out of spec.
And your graduate level statistics class is not going to do us any good here.   ;-)

Bottom line:  Future uBitx's should meet spec.
On present units it would be best to clean them up, though our power levels are low enough
that they may cause less bother than a 100W rig that does meet spec.
I for one will clean mine up.

Jerry, KE7ER
 


On Wed, Aug 8, 2018 at 08:06 PM, Jack Purdum wrote:
When I hear a target of -43dB, what does that really mean? That number or lower? That number plus or minus 3 sigma? I don't know and probably don't want to find out. Still, within -2dB of the target? I wonder.
 

Re: Good news, bad news

Tom, wb6b
 

That was an interesting question. Not knowing I bravely googled around and tried to separate the plausible from the non-plausible explanations. 

Around 2010 gcc removed the dead code warning option for being "unreliable". However, apparently later, the optimizers were improved to better automatically remove dead code. Or so the internet lore goes. 

Another fun thing, for embedded systems, is the lack of runtime error reporting (where is it going to be reported to). Code that does awful things, divide by zero, jumps to or accesses incorrect memory, probably other things, the embedded runtime will ignore the error and keep on running. With whatever unpredictable results that may cause. 

In large scale systems we instrument our code and the instrumentation data if collected by other analysts systems. Would be nice if the Arduino at least kept some counters on run time faults I could access and report in debug data. I'm looking around to see if they do exist. 

Tom, wb6b

Re: Good news, bad news

Mike KK7ER
 

I was looking for something like this for my day job and found that Coverity will do static code analysis and is free.  Wouldn't work for me because I cannot upload my company's proprietary code to the cloud.  But for open source it seems like a great tool:  https://scan.coverity.com

73 Mike KK7ER

Re: Ok.. I got the S-Meter working.. now the display with the new nextion software does not..

Kevin Rea
 

thanks Joe, I went to the page and I search for the word stretch but nothing came up. Would you have an exact URL for this?
Kevin

Re: About outta spec signals...

Gordon Gibby <ggibby@...>
 

Alyson, thank you for that photograph;  that helps explain more of the issues .....   lots of  cutting of traces and jumper re-wiring will be needed to straighten that out. (if possible) 

Relays need to either send the signal to an individual filter, or else ground out that filter.

Picture will help me understand the existing wiring!   I hope to just leave those relays there and rewire how they are used...........







On Aug 8, 2018, at 23:08, ajparent1/KB1GMX <kb1gmx@...> wrote:

Kees,

That is why I gave the full substitution procedure and a plug for your attenuator.

Rigol made it cheap and easy to answer those nagging questions.

Allison

Re: Harmonic performance - SSB vs CW

rcbuck@...
 

On Wed, Aug 8, 2018 at 01:50 PM, Jerry Gaffke wrote:Substituting a PX1002
PX1004 would also work at 1/2 the cost of the PX1002.

Ray,
AB7HE

Re: S-Meter on Ubitx, trying to get to work..

Kevin Rea
 

Thanks Bill 

Re: About outta spec signals...

ajparent1/KB1GMX <kb1gmx@...>
 

Jack,

For the bureaucratic it means not less than.  That is the part 97 words.

For the practical it means to the level of accuracy attainable +-1db is accepted.
if your using a 1db/step attenuator.  It is actually pretty accurate.

However a factor of more than 10 off is more than gross error.  
I sampled 5 units, I guess they were plumper back when. ;)

To be serious I like simple and low cost gear and fun kits as well.  I am
one to encourage it and people to build.  I do not feel lied to or mislead.
I may be one of a few that go back to the development of the unit. That
is when it was launched as early 2016 HF1 on freelists.org  and the
minima single conversion scheme with 20mhz filter was dropped. 
So I was there and still am.  I will say now what I said then spurs will 
be an issue and filters are the solution everything else was wishing.

So this discussion is not a surprise to me and was had before.

Allison