Date   

Re: End Fed antennas w/ uBITX #ubitx

Jack, W8TEE
 

Try studying Ph.D. level economics. Without the assumption of ceteris paribus, we'd be outta business.

Jack, W8TEE

On Thursday, July 26, 2018, 3:14:16 PM EDT, Mike aka KC2WVB <rb5363@...> wrote:


Allison,


You got it a bit backwards. Models don't lie rather it is the assumption that the model matches the boundary condition that essentially is the lie. It is also that things get too tough for humans to reasonably model phenomenon with mathematical physics that is problematic because we tend to use a simpler model with less complex boundary conditions that we fail to see is not sufficient for the puzzle at hand.

On Thu, Jul 26, 2018, 3:08 PM ajparent1/KB1GMX <kb1gmx@...> wrote:
Mike,

Amen.  Math and all are needed and useful.  Models based on them can lie. 
Reason garbage in nets garbage out.    And some cases the math is completely 
valid and correct but you can't make one.  

The best case of that I know as an engineer is "non Foster Matching"  it works
on paper but try and make a circuit that emits negative reactance and is stable.
The real world runs on paper but electrons don't care a whit.

Allison
 


ubitx with ft8 on wsjt-x with easydigi interface

Kevin Rea <reakevinscott@...>
 

hi guys,
ok, so i have all of the above working, i think...but do i set the ubitx to USB or CW  for ft8 on 20 meters.

kevin rea


Re: End Fed antennas w/ uBITX #ubitx

Tom, wb6b
 

This quote is attributed to John Von Neumann. 

"With four parameters I can fit an elephant, and with five I can make him wiggle his trunk." 

Complexity in models can be better, but at least some reflection on whether it is a forced fit is in order. We will always be struggling with the basic assumptions.


Re: uBITX Increasing 28 Mhz output by changing C81 #ubitx-help

Tom Cooper
 

It seems like every time I try to bridge a surface mount resisitor, like I did in my search for more power, the resistor dies.  I replaced R941, 942 and 96 last night with leaded resistors soldered to the pads, since my efforts to increase power caused a loss.  Now I get 10W out on 80, 40 and 20, 5W on 30, 17 and 15 and 2W on 10 with a few 2n2222a's and 270pf caps added.  If your results are poor, suspect those sneaky resistors.

73,

Tom  W1EAT


Re: End Fed antennas w/ uBITX #ubitx

Jerry Gaffke
 

So how do you suggest we handle such disputes within the context of this forum? 
Find out who all has a PhD, ask them to form a committee to pass judgment?

I prefer arguing it out till (hopefully) we can agree on a way to test the various hyphotheses.
Which is to say I prefer science, not politics.  
Yes, I have somehow managed to avoid the politics of post-graduate academia.

Jerry 



On Thu, Jul 26, 2018 at 12:40 PM, Mike aka KC2WVB wrote:
Ok, Jerry if your really interested in truth prevailing rather than calling it as you see it prevailing then there is only one tried and true method. It is what civilized people do when they present their argument to a committee of PHD's that are expert in the area of concern and either the argument is accepted or faulted. I know this because I have been tested in this manner, any other method is a bit sophomoric but unless you have gone through the process I don't expect you to agree and so be it.


Re: End Fed antennas w/ uBITX #ubitx

Mike aka KC2WVB <rb5363@...>
 

Ok, Jerry if your really interested in truth prevailing rather than calling it as you see it prevailing then there is only one tried and true method. It is what civilized people do when they present their argument to a committee of PHD's that are expert in the area of concern and either the argument is accepted or faulted. I know this because I have been tested in this manner, any other method is a bit sophomoric but unless you have gone through the process I don't expect you to agree and so be it.


On Thu, Jul 26, 2018, 3:32 PM Jerry Gaffke via Groups.Io <jgaffke=yahoo.com@groups.io> wrote:
You might be speaking to me, and feel my response has been too harsh.

If someone told me something in casual conversation that I knew to be wrong,
I might tell them so, and walk away if neither of us could convince the other. 

Here we have a forum with perhaps thousands following the conversation,
trying to make sense of all this.  For some readers, it will be the loudest or most
persistent voice that carries the argument.  

If I see something of consequence proclaimed here that I know is wrong,
I will not just let it ride.  That's a disservice to everyone else here who might choose
to act on that information.  If it bruises an ego somewhere, that's arguably better
than a hundred forum readers wasting time and/or money trying to follow through.

I try to keep it civil, and acknowledge that others may be equally convinced 
that I am wrong.  The ideal is that the conversation comes to a test, 
such as the back to back broadband transformer test of post  54981 
 
Sometimes, both sides can be correct.
This is not one of them.
Issues like this are best resolved, not left hanging.

>  Likewise 2+3 does not necessarily equal 5 for depending on the circumstances 2+3 may equal zero.

Oooh, perhaps we should start a new thread.
That definitely passes the "of consequence" test.  ;-)

Jerry, KE7ER


On Thu, Jul 26, 2018 at 11:30 AM, Mike aka KC2WVB wrote:
I can't say I like the tone of some of the comments found in the end-fed antenna threads. I am also reminded of a friend of mine who holds a PHD in electrical engineering who claims most EE's without advanced degrees really don't know anything other than the algorithms they have learned to take on faith and that when things get too difficult what they have taken as gospel is not necessarily the case.
 
In 500 BC the belief held by the knowledgeable including Plato was that any distance between two points was either an integer value or a ratio of integers. They could not see how it was not as they saw it. Likewise 2+3 does not necessarily equal 5 for depending on the circumstances 2+3 may equal zero. Also for any pair of numbers from a set it is not necessarily true that an order relation exists such that one is less, equal, or greater than the other and I am sure there are those that do not see how that can be but indeed it can be the case. It is when contradictions manifest themselves that do not coincide with cherished beliefs that new understanding is found and rather than sit on one's high horse looking down on those that challenge old ideas the really great thinkers of the ages have found the greater understanding that is waiting if one has courage to look.


Re: End Fed antennas w/ uBITX #ubitx

Jerry Gaffke
 

You might be speaking to me, and feel my response has been too harsh.

If someone told me something in casual conversation that I knew to be wrong,
I might tell them so, and walk away if neither of us could convince the other. 

Here we have a forum with perhaps thousands following the conversation,
trying to make sense of all this.  For some readers, it will be the loudest or most
persistent voice that carries the argument.  

If I see something of consequence proclaimed here that I know is wrong,
I will not just let it ride.  That's a disservice to everyone else here who might choose
to act on that information.  If it bruises an ego somewhere, that's arguably better
than a hundred forum readers wasting time and/or money trying to follow through.

I try to keep it civil, and acknowledge that others may be equally convinced 
that I am wrong.  The ideal is that the conversation comes to a test, 
such as the back to back broadband transformer test of post  54981 
 
Sometimes, both sides can be correct.
This is not one of them.
Issues like this are best resolved, not left hanging.

>  Likewise 2+3 does not necessarily equal 5 for depending on the circumstances 2+3 may equal zero.

Oooh, perhaps we should start a new thread.
That definitely passes the "of consequence" test.  ;-)

Jerry, KE7ER


On Thu, Jul 26, 2018 at 11:30 AM, Mike aka KC2WVB wrote:
I can't say I like the tone of some of the comments found in the end-fed antenna threads. I am also reminded of a friend of mine who holds a PHD in electrical engineering who claims most EE's without advanced degrees really don't know anything other than the algorithms they have learned to take on faith and that when things get too difficult what they have taken as gospel is not necessarily the case.
 
In 500 BC the belief held by the knowledgeable including Plato was that any distance between two points was either an integer value or a ratio of integers. They could not see how it was not as they saw it. Likewise 2+3 does not necessarily equal 5 for depending on the circumstances 2+3 may equal zero. Also for any pair of numbers from a set it is not necessarily true that an order relation exists such that one is less, equal, or greater than the other and I am sure there are those that do not see how that can be but indeed it can be the case. It is when contradictions manifest themselves that do not coincide with cherished beliefs that new understanding is found and rather than sit on one's high horse looking down on those that challenge old ideas the really great thinkers of the ages have found the greater understanding that is waiting if one has courage to look.


uBitX SSB transmit oscillations on 40m only #ubitx

Bruce
 

uBitX v3 oscillation and audio from speaker when transmitting on 40m. I'm looking for (1) anyone else who has this whether they have fixed it or not and (2) suggestions on how to diagnose it. I have a 200MHz dual channel analog oscilloscope, an RF-output interface to the 'scope, a power-SWR meter, a dummy load, a 5-band horizontal loop antenna, and a digital multimeter.

Tried all the other bands on SSB with no problem. Clean on CW with expected power out from 12w at 40m and below tapering off to 1w at 28MHz. During 40m SSB oscillation, it is heard through the speaker or headset. On the other bands the audio output is silent. Here is what I have tried and still the oscillations occur:

1. Change microphones; tried 3, oscillations continue with slight level differences between mics
2. Disconnect audio output devices; speaker, headsets
3. Disconnect USB cable extension that runs from Arduino to back of enclosure (saw a comment on that on this site.)
4. Change ground placement on SO-239
5. Connect dummy load directly to SO-239 with no transmission lines
6. Test with metal top on and then off enclosure
7. Test using 12.3v battery and using 13.8v power supply (didn't make sense but why not)
8. Wrapped microphone cord in ferrite clamps at plug and at microphone head
9. Use 1.2:1 40m meter antenna instead of dummy load
10. Check microphone jack wiring, continuity to ground, etc.

I have video and audio of 20m vs 40m if that helps.


Re: End Fed antennas w/ uBITX #ubitx

Mike aka KC2WVB <rb5363@...>
 

Allison,


You got it a bit backwards. Models don't lie rather it is the assumption that the model matches the boundary condition that essentially is the lie. It is also that things get too tough for humans to reasonably model phenomenon with mathematical physics that is problematic because we tend to use a simpler model with less complex boundary conditions that we fail to see is not sufficient for the puzzle at hand.


On Thu, Jul 26, 2018, 3:08 PM ajparent1/KB1GMX <kb1gmx@...> wrote:
Mike,

Amen.  Math and all are needed and useful.  Models based on them can lie. 
Reason garbage in nets garbage out.    And some cases the math is completely 
valid and correct but you can't make one.  

The best case of that I know as an engineer is "non Foster Matching"  it works
on paper but try and make a circuit that emits negative reactance and is stable.
The real world runs on paper but electrons don't care a whit.

Allison
 


Re: End Fed antennas w/ uBITX #ubitx

ajparent1/KB1GMX <kb1gmx@...>
 

Mike,

Amen.  Math and all are needed and useful.  Models based on them can lie. 
Reason garbage in nets garbage out.    And some cases the math is completely 
valid and correct but you can't make one.  

The best case of that I know as an engineer is "non Foster Matching"  it works
on paper but try and make a circuit that emits negative reactance and is stable.
The real world runs on paper but electrons don't care a whit.

Allison
 


Re: End Fed antennas w/ uBITX #ubitx

ajparent1/KB1GMX <kb1gmx@...>
 

Jack,

I tend to test.  To do that I build  and evaluate, its the engineer in me.  Over the years the number
of antennas built and tried and tested are numerous.  I also look at new and odd as a interesting
challenge to understand it or see if its all that or has a particular characteristic that can be useful.
That and antennas are fun to build.

But there are more than a few that have emerged as goto designs for HF.  End feds are one both
resonant and not, full wave loops or rectangles being some. 

Allison


Re: The dreaded LSB and USB swap problem again

 

Jacob,

Thanks for pointng me in the general direction. I used the uBitx Memory Manager and loaded Ian’s example calibration values into my uBitx, so now I'm at least up and running. I’m 200hz high in frequency and the BFO setting is off a bit because the audio is very bassy but at least I can tweak it from here. I have to figure what value to enter to get it closer on frequency. The stock calibration routine is totally broken. I was able to use it on my first uBitx successfully but it totally does not work anymore.

Joel
N6ALT


Re: End Fed antennas w/ uBITX #ubitx

Mike aka KC2WVB <rb5363@...>
 

I can't say I like the tone of some of the comments found in the end-fed antenna threads. I am also reminded of a friend of mine who holds a PHD in electrical engineering who claims most EE's without advanced degrees really don't know anything other than the algorithms they have learned to take on faith and that when things get too difficult what they have taken as gospel is not necessarily the case.

In 500 BC the belief held by the knowledgeable including Plato was that any distance between two points was either an integer value or a ratio of integers. They could not see how it was not as they saw it. Likewise 2+3 does not necessarily equal 5 for depending on the circumstances 2+3 may equal zero. Also for any pair of numbers from a set it is not necessarily true that an order relation exists such that one is less, equal, or greater than the other and I am sure there are those that do not see how that can be but indeed it can be the case. It is when contradictions manifest themselves that do not coincide with cherished beliefs that new understanding is found and rather than sit on one's high horse looking down on those that challenge old ideas the really great thinkers of the ages have found the greater understanding that is waiting if one has courage to look.

On Thu, Jul 26, 2018, 2:11 PM Jerry Gaffke via Groups.Io <jgaffke=yahoo.com@groups.io> wrote:
A crappy design that sometimes works is indeed crappy.
But don't confuse that with a crappy copy of a good design.

At any rate, truly figuring out exactly why something is crappy can be time well spend.  
The stock uBitx is not top drawer in some respects.
But it has been well worth my time, I've learned a lot. 

Jerry, KE7ER


On Thu, Jul 26, 2018 at 10:54 AM, Gordon Gibby wrote:
Crappy designs are not worth wasting your time on unless you really don’t mind having a lower chance of success—-which is probably just fine for many people! It is well worth THEIR time!!


Re: End Fed antennas w/ uBITX #ubitx

Jerry Gaffke
 

A crappy design that sometimes works is indeed crappy.
But don't confuse that with a crappy copy of a good design.

At any rate, truly figuring out exactly why something is crappy can be time well spend.  
The stock uBitx is not top drawer in some respects.
But it has been well worth my time, I've learned a lot. 

Jerry, KE7ER


On Thu, Jul 26, 2018 at 10:54 AM, Gordon Gibby wrote:
Crappy designs are not worth wasting your time on unless you really don’t mind having a lower chance of success—-which is probably just fine for many people! It is well worth THEIR time!!


Re: End Fed antennas w/ uBITX #ubitx

Jack, W8TEE
 

Yes, I knew that, and I'm an empiricist, too, and prefer a priori evidence of things. That said, if someone shows me something new, I can find it interesting even without empirical testing. I happen to have two ham sticks and am...some day...going to use them as a vertical dipole and see what happens. I think there are a lot of us out here who want a portable antenna that "works" and will worry about the theory later on. Also, I was just showing something "interesting" and was not looking for her treatise on why it wouldn't work, especially since the video shows it does work. True, it would be nice to have all the numbers, but that's not why I showed it. It was to simply show an interesting alternative portable antenna that works.

Jack, W8TEE

On Thursday, July 26, 2018, 1:33:32 PM EDT, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:


Jack,

Allison's an engineer.
When somebody talks about "performance", she wants numbers, not just anecdotal evidence.
Like radiation efficiency.
Otherwise it's just talk.

From     https://en.wikipedia.org/wiki/QRP_operation
"The current record for a QRP connection is 1 µW for 2640 kilometers (1650 miles) on 10-meter band (28-29.7 MHz)."

So heck, why all this complaining about low output on 10m with the uBitx.    ;-)
Well, at least it's interesting.

Jerry

On Thu, Jul 26, 2018 at 10:14 AM, Jack Purdum wrote:
Allison:
 
Did you watch the video? At the end he does show a screen shot of an 817 running 5W and making a contact in France. True, conditions may have been good that day and he is on a mountain top near the East coast, but your "claims and not actual performance" comment seems misplaced. Also, you'll note I used the term "interesting", not "efficient" or "best" or anything else. For someone operating under restrictions, it may provide an "interesting" way to at least get on the air. I read one ham who made contacts with a string soaked in salt water. I found that interesting, too. Personally, I could care less about the theory why is shouldn't work than I do about what the guy did to get it to work.
 
Jack, W8TEE


Re: End Fed antennas w/ uBITX #ubitx

ajparent1/KB1GMX <kb1gmx@...>
 

Jack

Yes I watched, I do that too as its fun! I have an 817 as well and impromptu radio is
something I enjoy.    It also proves rule 3.  

Now the question is did you read what I wrote?  Never said impossible or even unlikely.
In another post I wrote about a contact I made while mobile with one similar whip to VK land
foundation station QRP SSB.  I can go on with anecdotal  stories. If there is a favorite
pass time I have is is busting pileups with QRP SSB power and wimpy antennas.  Why,
it is fun and it is a challenge to do it..   If there is a point its not about antennas but doing
something even with marginal antennas.

The comment is well placed as it also points to how even a small change can improve
the likelihood of working DX rather than luck.   There is a direct relationship of height to 
antenna functional performance.  At low height even a small increase can be significant. 
But to stab the point again he was on the air doing something.

FYI: Anyone see the cover of QQ with the VE3IPS crutch antenna?  Imagine a pair of
metal crutches 8ft up on a Buddypole mast with a 4:1 transformer to help match it
and a T1 or similar tuner for 40 through 10.  That impresses me for shear fun and
effectiveness.  Why?  Because he did it and the flare of the crutch makes it
something like a bicone or fan in that it adds area and that helps bandwidth!   
Efficient, not likely but when it comes to fun that hits my he's having fun button.   
He didn't make any claims other than it loads 40 though 10.  I can't see why he would
not make contacts on it. 

Allison


Re: 2 uBitx available for donation to club

Tim Young
 

Hi Alan Kessler:

Both have been spoken for.

Thanks

Tim


Re: 2 uBitx available for donation to club

Gordon Gibby <ggibby@...>
 

That’s awfully nice of you!


On Jul 26, 2018, at 13:38, Tim Young <tyoung@...> wrote:

John I will send you the kit

Alan I will send you the completed version

Thanks

Tim
WB7UVH


Re: End Fed antennas w/ uBITX #ubitx

Gordon Gibby <ggibby@...>
 

“Jack,

Allison's an engineer.
When somebody talks about "performance", she wants numbers, not just anecdotal evidence.
Like radiation efficiency.
Otherwise it's just talk.”

There you go! With 150 DB to throw away, almost anything can work SOME of the time— exactly as Alyson pointed out, even a salt impregnated string. SOMEtimes.

However as some other fellow is continuing to point out, there are some crappy designs that will work a lot LESS “some of the time.” Allyson keeps pointing out that there are better designs that will work MORE “some of the time”.

Crappy designs are not worth wasting your time on unless you really don’t mind having a lower chance of success—-which is probably just fine for many people! It is well worth THEIR time!!

It’s a free country, you can use just about anything you want as long as you stay inside the frequency bands.


My own preference is for devices with low losses. Another words high-efficiency. Since I don’t know who I need to reach in whatever emergency comes next, I generally want a bit of NVIS performance.

I agree completely with Allison’s three rules, the higher the antenna, (at least above obstructions, although maybe not much more because I need some NVIS); The more wire, especially if it is wisely placed! ; and “anything beats nothing”

We have had a ton of fun building homemade to meter SlimJim antennas on one by two pressure treated lumber, in technician license classes, they are all over town up in Pinetree’s, providing packet node networks. They even have some EMP rejection. And I guess you could say somewhat nearby lightning protection, what with that low frequency dead short they have;

I’ve done a tiny bit of work with Them, and I am thoroughly convinced that a 50 foot high antenna with crappy coax will magnificently beat the same antenna at 15 foot high with wonderful coax on 2 meters ; because attenuation through houses and cars is way higher than attenuation through RG8X

On Jul 26, 2018, at 13:33, Jerry Gaffke via Groups.Io <jgaffke=yahoo.com@groups.io> wrote:

Jack,

Allison's an engineer.
When somebody talks about "performance", she wants numbers, not just anecdotal evidence.
Like radiation efficiency.
Otherwise it's just talk.


Re: 2 uBitx available for donation to club

Truffies
 

My name is Alan Kessler WB2BQK

I am writing on behave of Royal Palm Beach Amateur Radio Club in Florida a very strong club in community service.

WE are a club with 60 members, I have been trying to get this as a project to cover the age and knowledge spend of the club (82 to 16 age and newbies to over 70 years in radio)

This would get the idea rolling to keep a old club going and not dying out.

I would be willing to pay myself all shipping to save the club and set a great teaching and learning project with in.

73's

Alan Kessler

-----Original Message-----
From: Tim Young
Sent: Jul 26, 2018 12:44 PM
To: BITX20@groups.io
Subject: [BITX20] 2 uBitx available for donation to club

I would like to donate two uBitX to a group or club that could benefit from it. One is assembled with the VE1BWV audio pop mod in the W5BEK enclosure. The other is un-assembled and includes the inkits enclosure. I will cover shipping in the US.

Tim
WB7UVH