Re: Follow-up Antuino question
The H and P works only with an already stable vfo that has a long term drift under the locking range. It cant fix a badly made VFO. That said, I should repeat that a stable VFO is so not merely by design but construction and choice of components.? For instance, if you use the standard disc ceramic caps, it is bound to drift. If you keep it open without a shield it will drift too. At times, the heat from a regulator can move the frequency. A stable vfo is made with a few rules of thumb: 1. Build the entire VFO circuit using point to point wiring directly soldering component leads to each other. Keep the leads short but dont stuff them very close together. 2. Use polystyrene capacitors if you can. These are transparent capactors with silver colored body cylindrical bodies. They are available from mouser. You will need high value (about 100pf caps paralled up) for resonating at the design frequency and low value (2.2pf) for coupling to the JFET. 3. Use either a T50-6 toroid or an air core inductor wound on a relatively stable thermal expansion. A teflon rod is a good alternative..so is a test tube. A drinking straw is not! Even free standing copper inductors change their shape as copper expands the wiring. It has to be held in place with clear nail polish lacquer. 4. Avoid the polyvaricons, they are noisy, rough tuning and drifty. Hunt around for the old, all metal broadcast tuning capacitors. Mount the VFO board on the tuning capacitor or mount the tuning capacitor on the VFO board. No loose wires! 5. Mount the regulator at least 2 inches away from the VFO's capacitors and the inductor. 6. For low noise operation, a JFET is the best choice. You have to bypass the voltage regulator at the input too, as well as the output. Mosfets make noise VFOs due to their increasing flicker noise at lower frequencies. 7. Avoid using varactor diodes, they are meant for PLLs where drift of the VCO is a given. A varactor that is used as fine tuning over a few khz is acceptable in parallel to a tuning capacitors. The drift will be proportionally less. A combination of a variable tuning capacitor and a varactor over a small range is a good, backlash free alternative to a good slow motion drive. With these guidelines, it is possible to consistently produce VFOs that are stable enough for CW and SSB work. Even PSK31 and FT8 are possible with effort. An interesting idea is to cancel the thermal drift by using a diode like the 1N914 to sense the increased ambient temperature and provide correction offset DC to the varactor. I am worried that we are losing the skill to produce VFOs. It is fundamental to our persuasion. Generating stable and clean RF is the start of any radio project.
Tom
You got it!? analog VFOs used to drift all over the band.? Then came the Vackar design? which was very stable.? Next seems to have been H&P which made even a? Vackar design? better (cheaper components and less stringent builds) stabilized by H&P).? With PIC? and AVR/Arduino?came really good and inexpensive FLL designs.? PLLs were always? available, but seen by many as too complex and expensive (not really true but still hard? to dispel?the myth, mystique, hype, and traditions).
H&P was seen as an easy and quick fix for old equipment with drifty VFOs.
Arv _._
On Sun, Nov 15, 2020 at 5:24 PM Tom, wb6b < wb6b@...> wrote: 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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Patrick,
If you cannot work out the Xloader issues, then you can download the source code from the same link as the hex files.? It is a different zip file.
If you go that route, then you will need to go into the ubitx.h tab and be sure to set the?
#define UBITX_BOARD_VERSION 5? ? ? ? ? ?//v1 ~ v4 : 4, v5:?
to a 4, and select the correct display in the following lines.? Then compile and load.?
Since you have loaded a program to the Nano before, I assume that what you have works with the Raduino Nano.
I believe that the Xloader download has security issues in that it is not registered.? That means you need to allow it to download and then run.? I kind of remember the concern I had with bypassing the Windows security feature.
Feel free to post with specifics of your error messages if you need more help.? It is always best to do so in this same thread so that others can follow and learn.? If you would rather do so out of the groups.io then private message me if you wish.
73
Evan
AC9TU
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Re: Can¡¯t shut off emails from this group
Thanks Arv, will let you know.?
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Frank,
As far as I know, there is not an official way to adjust RV1.? It is a drive setting that I have used to set the output of the PA to a value that is about 12 Watts on 80 meters in CW mode with 13.8 volts supplied.? I have not tried to push the finals beyond that point with 13.8 volts.? Even so, RV1 tends to be close to the maximum level (fully counter-clockwise) to get that value. It seems that it was more a way to reduce power than adjusting to a point where later stages are overdriven.?
One of these days I will get around to measuring the effect on output purity.? So far have not had any issues with the above setting process.? I have tested my rigs for harmonic and spurious.? I have not tested for linearity other than from signal reports and monitoring with my other rigs.
73
Evan
AC9TU
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Hi Evan , Thanks for Your Reply .? Yes , I seem to have uploaded the? wrong? firmware onto the Arduino Nano . I did origionally try the KD8CEC Software but the links?
? ? ? ? ? ? ? ?on his site didnt work for me . Spent a lot of time today and? ran into computer problems . Discovered that XLoader downloads? wont open on 1 Laptop?
Downloaded it onto a different laptop and cant put files onto the XLoader Box .... My Head was wrecked with all these problems? but I am 80% there tonight !
May even go back to the origional v4.3 firmware !??
Thanks Again for replying to my query and for sending me the links to the various bits of software ....all very helpful , Evan ..
Know a lot more tonight than I did last night !?
Thanks Again , Evan?
Kind Regards?
Patrick?
Ei2if?
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Re: Follow-up Antuino question
Tom
You got it!? analog VFOs used to drift all over the band.? Then came the Vackar design? which was very stable.? Next seems to have been H&P which made even a? Vackar design? better (cheaper components and less stringent builds) stabilized by H&P).? With PIC? and AVR/Arduino?came really good and inexpensive FLL designs.? PLLs were always? available, but seen by many as too complex and expensive (not really true but still hard? to dispel?the myth, mystique, hype, and traditions).
H&P was seen as an easy and quick fix for old equipment with drifty VFOs.
Arv _._
On Sun, Nov 15, 2020 at 5:24 PM Tom, wb6b < wb6b@...> wrote: 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
On Sun, Nov 15, 2020 at 04:28 PM, Arv Evans wrote:
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.
It is amazing how inexpensive standard frequency crystals are nowadays. No need to scrimp there. Maybe, for prototyping, just wire the components together with a brand new crystal, unsolder the old resonator and solder the new little assembly in its place. Rather than cutting and jumpering on the board. Tom, wb6b
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OK Jerry , Thanks for your reply . I think my problem is the wrong software / firmware is on the Chip and it isnt compatible with the Version 4.3 Board .
Have learned a lot in the last 24 hours ....but it sure is a lot od trial and error !
Thanks?
Patrick?
Ei 2if?
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Re: Can¡¯t shut off emails from this group
I think it is fixed, but let me know if the problem persists.
Arv _._
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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Re: Can¡¯t shit off emails from group
Jaytee1
I just now logged in as administrator and found that you have successfully changed your? email handling to "no email".? Just to be sure I also set it to "no email".? That should fix? things but if not please let me know so I can take a longer look at what might be happening.
Please take a look at message headers to be sure that the offending messages are from? the [email protected] group.? It might be possible that those?unwanted emails are from? some other similar?group.
Thanks
Arv _._
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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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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Patrick Peter Rosney
Bob Lunsford