SO I have searched and searched, what is the adjustment for RV1 please.
--
Frank, KG9H
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Re: Can¡¯t shit off emails from group
Okay.? Hold on for a few minutes and I will log in as administrator and see if I can? change this for you.
Arv? K7HKL _._
I accidentally deleted my post about this.
Arv suggested to log in and change from ¡°view all¡± to ¡°view digest¡± Thanks Arv for the help :-)
I have selected ¡°No emails¡± ?and am still receiving them. Why does this function not work?
?Can include a picture of the setting options if that allowable.
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Re: Follow-up Antuino question
Tom
That sounds like an excellent idea.? Should be able to hold the CPU clock to within 1 Hz of? desired frequency.??
You might also change the ceramic resonator to a real crystal in your Arduino NANO boards for? added stability so the H&P does not have to work so hard.
? ??
Arv _._
??
On Sun, Nov 15, 2020 at 4:09 PM Tom, wb6b < wb6b@...> wrote: On Sun, Nov 15, 2020 at 01:54 PM, Tom, wb6b wrote:
This is an clever way to use an AVR chip to stabilize a 10mhz oscillator without a pre-scalier. Just use the 10 mhz oscillator as the main CPU clock.
Just a though. If I was willing to allow relaxed expectations for jitter and short term accuracy, I wonder if I could put a varactor diode in the xtal circuit already on an Arduino Nano and then adjust the 16mhz Nano clock to be very accurate; based on the 1 PPS signal from a GPS module?
Tom, wb6b
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Re: Follow-up Antuino question
On Sun, Nov 15, 2020 at 03:57 PM, Arv Evans wrote:
It tries to hover around one particular frequency.?
So in following the part of this thread that is strictly related to Huff and Puff, was the original reason for the Huff and Puff circuit to create a manual VFO that would jump and hold in accurate increments rather than be free to drift around uniformly. A way to allow operators to dial up drift-free discrete frequencies before digital frequency synthesizers became the primary way to set the frequency of a radio? The non-drifting VFO settings were more the goal than the actual circuit details of Huff and Puff, itself. Huff and Puff was likely chosen because it was easily implemented with a simple type-d flip-flop, in the pre microprocessors everywhere days? Tom, wb6b
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Re: Follow-up Antuino question
Jerry?
I think we are still talking about two different animals.? H&P does not normally flip back and forth? between two different frequencies.? It tries to hover around one particular frequency.? If the VFO? drifts too much between the LF rate of sampling it may flip to the next frequency above or the next? frequency below, but that would be a very poorly designed H&P and/or VFO.??
This same argument about whether H&P is?a PLL, or FLL, or something entirely different was? carried on ad-nauseum several years ago and apparently is still not resolved.? It does not? work to think of H&P as a phase based PLL.? Using PLL terms to describe H&P really doesn't? seem to work because it leads newbies astray.
Slowing (delaying) the steering voltage between edge-comparisons just does exactly?that...delays? application of the steering voltage and delays correction of frequency.? Since a PLL works on? phase, or position of a cycle, while H&P works on only one specific part of a cycle (edge detection). PLL correction may be averaged and delayed, but not H&P because that would just make its? compensating action less related to the actual edge-detection sampling event.
Some early descriptions and builds of H&P just pushed the VFO in one direction only.? These? required one to determine the direction of VFO drift and only compensated in the opposite direction. These can usually be noticed because they typically had a switch to reset the steering voltage? if it accidentally drifted out of correction range.??
Modern H&P design usually does not have a "conditioner" stage between the VFO (analog signal)? and the D-FF,?like is?described in EMRFD.? This can insert some small jitter because an analog? signal driving an input of the D-FF may not always trigger at exactly the same voltage point, but I? have never observed this in my own builds.
The EMRFD writeup on H&P seems overy? complex, and whoever wrote it seems a bit confused? regarding how all the proposed pieces really work in their circuit.? I doubt if the authors ever built? their design?
Present day H&P has evolved quite a lot since it was popularized by the?PA0KSB? article from April 1973 Electron magazine.? Hans G0UPL picked up on the? PA0KSB design and several of us played with the idea and arrived at different ways? to accomplish the same end result.
There are also other methods of frequency stabilization, such as the Wadley Loop system.
? ??
Arv _._
There are lots of variants to doing a Huff and Puff.
EMRFD shows a very basic example on pages 4.5 and 4.7.
In this design, the frequency is constantly bouncing somewhere
between two frequencies that are 40hz apart.?
If the VFO is stable enough, one could slow down the loop filter between
the Huff and Puff detector and the varactor diode in the VFO, such that it
takes a minute or two (instead of under a second) before a change in
VFO frequency causes a significant change to the varactor correction voltage.
This would make the output frequency much more stable, but would take some time
to settle in after you manually tune the VFO.
The advantage of Huff and Puff is that you can make the VFO lock to
discrete steps without having to reprogram the dividers with each frequency change
as you would on a standard PLL.? Where a standard PLL will lock only to one specific?
frequency, a Huff and Puff might lock to any frequency that is an even multiple?
of 100 Hz. I doubt you could borrow a phase-frequency-detector directly
from a PLL design and have it work in a Huff and Puff.
Tom would almost certainly be better off with a standard PLL design
for his GPS stabilized crystal reference oscillator.
Huff and Puff isn't used a lot these days.? If you have a microcontroller in
the rig (such as the Nano on the Raduino), it's fairly easy to program the dividers
on a PLL device.? This will generally give a more stable output.? A PLL can allow
more resolution (much smaller steps) when choosing the output frequency.
Take the above with a large grain of salt.
I am no expert on either Huff and Puff or PLL's.
Jerry, KE7ER
On Sat, Nov 14, 2020 at 08:33 PM, Jerry Gaffke wrote:
It's been lots of years since I have looked at huff-and-puff oscillator stabilization.
What I wrote in that last post is incorrect, there's more going on here.
Jerry, KE7ER
Hide quoted text
?
On Sat, Nov 14, 2020 at 06:08 PM, Jerry Gaffke wrote:
This may be an alternate way of looking at what you are proposing.
I suspect you are describing a phase-locked-loop.
And that yes, you have tried it.
There's a phase-frequency-detector inside the Si5351.
The VCO in the Si5351 can be pulled anywhere between 600 and 900 mhz
(and quite a bit beyond, actually).
But if instead of that VCO we have a VFO that is first manually tuned very near the
target frequency, the error detection will have far less work to do.?
And the output will have far less jitter.
Jerry, KE7ER
?
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Can¡¯t shut off emails from this group
I accidentally deleted my previous email on this, reposted havre reposted again.
Arv suggested to change from ¡° View all¡± to View Digest.¡±. I have selected ¡°No emails¡± and am still getting every post. Does this function not work?
Thanks Arv BTW for the quick response earlier.
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After thinking I needed to get an SWR meter for checking my 2M Larson antenna, I suddenly realized I'd be miles ahead and better off with the Antuino. I ornded one on Saturday and hope to get it soon. I anticipate it is much better than an SWR meter and does not need to transmit a signal to check the SWR and, also, I can see which way the antenna is off frequency and make adjustments without even taking the 2M rig to the car. I still wonder how it is used to measure power, as I understand it does, and what power limits it will need to keep in mind. The idea it will measure QRP power and do it within 10% (plenty good enough1) is where I'll use it mostly but also may want to measure up to 100W. I expect more detailed instructions will come with the Antuino...
I believe I'll find the Antuino a bargain when added to the home equipment. I also anticipate doing a better job of alignment, possibly, by listening to WWV on 10MHz while listening to it on my HF rig. When I "swish" to the same frequency, I can then zero-beat the WWV and Antuino frequencies and see how far off the WWV signal is. Ha
I can also verify the frequency counter by reading the zerobeated signal and check what the frequency counter readout says. Another bonus feature. The WWV transmitted signal is not easily read with a frequency counter without some means of producing a usable related signal for the counter.
I see using the Antuino in ways I never used before. One or two uses I can use right away but the possibilities are many.
Bob ¡ª KK5R
On Sunday, November 15, 2020, 6:23:27 PM EST, iz oos <and2oosiz2@...> wrote:
Mine came too with the enclosure and perfectly aligned. The Output Port in SNA mode delivered in my unit more than -20dbm so for accurate measurements I use attenuators. Mine was one of the first produced by hfsignals and later production might be slightly different (i.e. even better).
Il sab 14 nov 2020 04:15 AM Bob Lunsford via <nocrud222= [email protected]> ha scritto:
Good news. Thanks. That's a clincher for me.
Bob ¡ª KK5R
On Friday, November 13, 2020, 10:10:57 PM EST, Evan Hand < elhandjr@...> wrote:
My Antuino came fully assembled in the enclosure shown.? The screen may be different depending on the version of software that is now being supplied by HF Signals
73
Evan
AC9TU
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Mine came too with the enclosure and perfectly aligned. The Output Port in SNA mode delivered in my unit more than -20dbm so for accurate measurements I use attenuators. Mine was one of the first produced by hfsignals and later production might be slightly different (i.e. even better).
Il sab 14 nov 2020 04:15 AM Bob Lunsford via <nocrud222= [email protected]> ha scritto:
Good news. Thanks. That's a clincher for me.
Bob ¡ª KK5R
On Friday, November 13, 2020, 10:10:57 PM EST, Evan Hand < elhandjr@...> wrote:
My Antuino came fully assembled in the enclosure shown.? The screen may be different depending on the version of software that is now being supplied by HF Signals
73
Evan
AC9TU
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Re: Follow-up Antuino question
On Sun, Nov 15, 2020 at 01:54 PM, Tom, wb6b wrote:
This is an clever way to use an AVR chip to stabilize a 10mhz oscillator without a pre-scalier. Just use the 10 mhz oscillator as the main CPU clock.
Just a though. If I was willing to allow relaxed expectations for jitter and short term accuracy, I wonder if I could put a varactor diode in the xtal circuit already on an Arduino Nano and then adjust the 16mhz Nano clock to be very accurate; based on the 1 PPS signal from a GPS module? Tom, wb6b
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Re: S-Meter Pin A7 Location V6
Another possible way to remove pins inserted in a nylon connector block is to use a common butt splice. After removing the insulation, cram the sleeve over the pin, into the nylon block, and this will force the retaining locks to disengage. It works for pins in some computer connectors, anyway. However, for pins smaller connector blocks, this scheme may not work unless a proper sized sleeve is found.
I have used the jeweler's screwdriver method also but one must be careful to avoid having the screwdriver get plunged into one's hand if not controlled properly OR if the screwdriver breaks off due not being all that strong.
I only bring this up because it may be something new to a few members here. I once had to go to the VA hospital to repair my hand after a screwdriver slipped and got plunged under the skin in the palm of my hand. Oops...!
Bob ¡ª KK5R
On Sunday, November 15, 2020, 4:41:52 PM EST, AndyH <awhecker@...> wrote:
Hi Mick,
? ?I received a V6.2 ?BITX about 6 weeks ago and confirm that my 'digital' connector looks like yours with the wires cut.
? ?You can use a small probe or small straight/minus screwdriver to push the tab on the side of the connector to remove/replace the cut wire on your existing connector.
? ? On the V6 radios, A7 from the Arduino comes out on pin 8 of the connector, same as my V3 and Evan's photo.? Here's the Raduino schematic for reference.? You're working on the 'mate' for the 'Controls1' connector:??
? ?Cheers and 73, Andy
On Sun, Nov 15, 2020 at 03:23 PM, Mick wrote:
Hello Evan
You're becoming my mentor - very much appreciated.
I assume then that the numbering of that plug starts at A-Zero one end (Black) though to A7 Purple at the other end.
My encoder arrived pre-wired with the purple, blue, green and orange wires cut off - please see photo.
The kit arrived with spare wired plugs though, so it's easier if I use the spare 8-way plug and just re-wire the encoder.
That leaves me with the other wires including the purple A7 wire to use as I wish.
If there is someone with a Version 6 ubitx I would appreciate confirmation, though it looks spot on Evan.
Thanks Evan, all the best? 73? Mick M0GWD
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Ditto, Evan. I'm constantly learning related and unrelated info here and hope no one is discouraged in posting their thoughts and results from their experiments. Personal gain from this is one of the major reasons I entered the forum.
Bob ¡ª KK5R
On Sunday, November 15, 2020, 10:19:11 AM EST, Evan Hand <elhandjr@...> wrote:
Richard,
The name of the group is BITX20, not uBITX.? It is really for homebrewing as well as the kits that came out of that effort.? Feel free to continue to post if you so choose.? We are all interested in the type of experimentation that you are doing.? I can speak for myself that I learn with all of the questions and answers on bidirectional transceiver work that is being done.
Have fun with the build!
73
Evan
AC9TU
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After watching the video in the first link below, I think this is a primo way to go. The video is excellent, in fact, at least in my opinion. However, this generates another question: If I install the AGC board from kit-projects, does it need to be place in the input path to help the AGC board work better or as designed? If it can go on the output path, the added filter board can be placed just to the left of the AGC board but it in the input path, then it has to be inserted some other way such as mounted vertically in the diagonal land going between the mounted AGC board and the relay just to the upper right of the AGC board.
Any thoughts on this? Two of the AGC boards are due in here on Tuesday, one for me and one for my son in Sacramento. The video at nearly the end shows a small, doable board that could be mounted vertically with one lead directly to the board and the other from the filter board down to the signal path (assuming the land is cut between the two connections). I hope I have created an easy-to-understand visual image from my mind to your.
Bob ¡ª KK5R
On Sunday, November 15, 2020, 7:45:25 AM EST, Gary Rindfuss <rindfussg@...> wrote:
Kit-projects sells a uBitx broadcast filter kit on the web page where they sell their agc board. It requires you to wind 3 tiny torroids but it works well.? There is another design you can build yourself that uses axial inductors it works well too. I have used one of each. The info on that is here:
On Sun, Nov 15, 2020, 5:28 AM Gerard < kabupos@...> wrote: Hello,
The other time when I did a search on E.. Y, with the keyword Ubitx, I came across this.
A filter, but I don¡¯t know any more...
cdt
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Good suggestion, Evan. I just called my son and he said he's too busy at the moment to go back and check but I forwarded your message to him to check this. I have heard that some super-duper toasters can also generate RF signals. The FCC apparently hasn't addressed this kind of unwanted signal generation ¡ª yet!
I also suggested to him that when he hears such signals to disconnect the antenna to at least get an idea if it's coming in as a transmitted signal but if a super-strong carrier is being generated at some unknown frequency, it could be some non-linear element in the signal path that is generating the harmonics (assuming they are harmonics) but this just helps isolate the signal/s from being generated in the V6 itself.
Let's hope that disconnecting the antenna is a useful part of the diagnosis. However, this still does not eliminate the possibility of it coming in over the power lines, either generated in the grid or more locally.
Mysteries have so many possibilities.
I'll let the forum know whatever my son may find out. He's a good ham with years of experience as a ham (since the mid-70's) but works as a contractor supervisor in Sacramento, CA and does not have all that much time for hobbying these days.
Bob ¡ª KK5R
On Sunday, November 15, 2020, 4:26:26 AM EST, Evan Hand <elhandjr@...> wrote:
Bob,
I would agree with Gary's suggestion to add the Broadcast Band high pass filter.??
I had a similar experience to your son's one afternoon.? All of a sudden I had birdies all over the band.? Turned out that my wife had started our new high-efficiency washer at that time.? When the washer stopped (30+ minutes later), the noise went away.? It could be that there is an appliance being run in the area that is generating a lot of noise.? Switching to battery power did not eliminate the problem so it was not just power line related.
I would have him try again and see if the problem persists.
73
Evan
AC9TU
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Re: Follow-up Antuino question
On Sun, Nov 15, 2020 at 01:43 PM, Arv Evans wrote:
Since H&P only corrects HF frequency during each cycle of the LF clock
there is a possibility of overshoot if the delta-C is too large.?
Hi Arv, This is good information you supplied while I was slowly working on my last message. So, the Huff and Puff method may introduce a constantly varying low frequency phase shift. That makes sense. In Hans' design he refers to using Huff and Puff in his xtal oven frequency adjustment method. But, because it uses a full microprocessor to generate the up and down voltage pulses, it may really be more of a sample and hold arrangement as a DAC. Not limited to correcting only when the phase delta reaches a certain point. I'll need to see what he did in his software. Tom, wb6b
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Re: Follow-up Antuino question
toggle quoted message
Show quoted text
On Sun, Nov 15, 2020 at 4:13 AM Gareth Evans via <headstone255= [email protected]> wrote: Bore da, Arv!
Sut dych chi?
(Dw i'n dysgu siarad Cymraeg!)
Related? There are teeming millions of we of the Evans clan!
On Sat, Nov 14, 2020 at 09:56 PM, Arv Evans wrote:
> Gareth Evans
>
> We have the same last name...are we related?? ?8-)
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Re: Follow-up Antuino question
This is an clever way to use an AVR chip to stabilize a 10mhz oscillator without a pre-scalier. Just use the 10mhz oscillator as the main CPU clock.
Here is a GPS stabilized frequency reference by Hans doing that.
Faster AVR chips above 20mhz could also work, but this simpler and provides the microprocessor with a very accurate clock, to boot.
If I use a similar design to making a GPS disciplined frequency standard, I might use a processor chip that has a digital to analog converter to do the crystal oscillator fine tuning. But the huff and puff is a DAC (a slow one) and may be as good as a "real" DAC for this application. Probably would not try to use PWM as a DAC in this case, as there may be a residual ripple at the PWM frequency.?
Somewhere I have an old crystal oven similar to what Hans used in his project. I'll need to see if it has a voltage input to adjust the frequency. Bought the xtal oven 20 years ago for a frequency counter project. So, after only 20 years the oven may finally end up in a project.?
If the oven is fixed frequency, but has a hole that can be uncovered to re-calibrate the frequency, maybe I'll move it so it is at the correct frequency is at a lower temperature than the thermostat setting in the oven and vary the temperature of the oven by controlling the heater voltage to keep it on track this the GPS 1 PPS reference. But, otherwise use Hans' design.?
Off to the garage to rummage through the many old boxes of junk (fine scientific radio apparatus) that has somehow resisted the sands of time.
Tom, wb6b
?
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Re: Follow-up Antuino question
Jerry
I suppose that in a very broad description one could say that H&P is a PLL. Just depends on how deep one wants to go into what the tiny gears are? doing deep inside.??
Arv ?
It's been lots of years since I have looked at huff-and-puff oscillator stabilization.
What I wrote in that last post is incorrect, there's more going on here.
Jerry, KE7ER
On Sat, Nov 14, 2020 at 06:08 PM, Jerry Gaffke wrote:
This may be an alternate way of looking at what you are proposing.
I suspect you are describing a phase-locked-loop.
And that yes, you have tried it.
There's a phase-frequency-detector inside the Si5351.
The VCO in the Si5351 can be pulled anywhere between 600 and 900 mhz
(and quite a bit beyond, actually).
But if instead of that VCO we have a VFO that is first manually tuned very near the
target frequency, the error detection will have far less work to do.?
And the output will have far less jitter.
Jerry, KE7ER
?
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Re: Follow-up Antuino question
Tom, wb6b
Using H&P to "stabilize"? a 10 MHz VFO or crystal oscillator with a low? frequency clock derived for GPS or WWV sounds interesting.? Way back? when we were playing with H&P, I did something similar but used the 60 Hz? mains as a reference clock.? That proved that using the mains as a? reference is not really a good idea.? Large current loads going?on and off? cause significant frequency shifts in mains.? I even visited a local mains power? hydro-electric generating station to see how mains frequency is controlled. They have a flow control system that uses a GPS clock for a frequency? reference.? This allows the mains frequency to move up or down by several? Hz but still maintains an average 60 Hz so our clocks are usually accurate.
Since H&P only corrects HF frequency during each cycle of the LF clock there is a possibility of overshoot if the delta-C is too large.? This stabilizes? for average frequency but at the same time it can introduce phase and? frequency jitter at the LF rate.
Very?low LF clock frequencies are interesting because the sampling rate can? become so slow that it actually allows frequency drift to occur, between? phase comparison samples.
It is possible to run the LF clock much faster. There are some examples of? this FAST H&P on Hans web site.
Your idea of H&P stabilization with an LF clock derived from GPS or WWV? is intriguing, but remember that H&P is never really stable.? It just holds? the HF part very close to some multiple of the LF clock.? Think of H&P as a? frequency multiplier that holds an HF signal close to some multiple of the LF? reference frequency.? It has jitter (frequency shift) but that is very slow and? is based on the LF reference frequency.
Arv _._
On Sat, Nov 14, 2020 at 8:27 PM Tom, wb6b < wb6b@...> wrote: On Sat, Nov 14, 2020 at 06:08 PM, Jerry Gaffke wrote:
But if instead of that VCO we have a VFO that is first manually tuned very near the
target frequency,
So it seems the Huff and Puff method is for providing the final little bit of frequency stabilization to a VFO that is already adjusted to oscillate very close to the desired frequency. Would the Huff and Puff method be one of the preferred ways to fine adjust the frequency of a 10mhz crystal oscillator to make a DIY GPS disciplined frequency reference?
Tom, wb6b
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Re: S-Meter Pin A7 Location V6
Hi Mick,
? ?I received a V6.2 ?BITX about 6 weeks ago and confirm that my 'digital' connector looks like yours with the wires cut.
? ?You can use a small probe or small straight/minus screwdriver to push the tab on the side of the connector to remove/replace the cut wire on your existing connector.
? ? On the V6 radios, A7 from the Arduino comes out on pin 8 of the connector, same as my V3 and Evan's photo.? Here's the Raduino schematic for reference.? You're working on the 'mate' for the 'Controls1' connector:??
? ?Cheers and 73, Andy
toggle quoted message
Show quoted text
On Sun, Nov 15, 2020 at 03:23 PM, Mick wrote:
Hello Evan
You're becoming my mentor - very much appreciated.
I assume then that the numbering of that plug starts at A-Zero one end (Black) though to A7 Purple at the other end.
My encoder arrived pre-wired with the purple, blue, green and orange wires cut off - please see photo.
The kit arrived with spare wired plugs though, so it's easier if I use the spare 8-way plug and just re-wire the encoder.
That leaves me with the other wires including the purple A7 wire to use as I wish.
If there is someone with a Version 6 ubitx I would appreciate confirmation, though it looks spot on Evan.
Thanks Evan, all the best? 73? Mick M0GWD
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Re: S-Meter Pin A7 Location V6
Hello Evan You're becoming my mentor - very much appreciated. I assume then that the numbering of that plug starts at A-Zero one end (Black) though to A7 Purple at the other end. My encoder arrived pre-wired with the purple, blue, green and orange wires cut off - please see photo. The kit arrived with spare wired plugs though, so it's easier if I use the spare 8-way plug and just re-wire the encoder. That leaves me with the other wires including the purple A7 wire to use as I wish. If there is someone with a Version 6 ubitx I would appreciate confirmation, though it looks spot on Evan. Thanks Evan, all the best? 73? Mick M0GWD 
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Bob Lunsford