Re: Inductor Q Measurement
How did you get it loaded and working?
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On Oct 12, 2021, at 3:09 PM, John Baines via groups.io <jbaines@...> wrote:
Andrew,
NanoVNA-saver works fine on my Mac.
73
John
M0JBA
On 12 Oct 2021, at 19:56, Andrew Kurtz via groups.io <adkurtz@...> wrote:
That program sounds wonderful! The only problem is that my computer is a Mac, and I bet it won¡¯t handle it. I know someone might say ¡°O just get Python and change XYZ while uploading ABC from Github¡.¡± and I might as well be listening to Greek. I have not yet succeeded in getting my nanoVNA data other than by hand-typing it into Excel because I can¡¯t get nanoVNAsaver to run. Any way to get your Coil program working on a Mac?
Andy
On Oct 11, 2021, at 7:00 PM, Brian Beezley <k6sti@...> wrote:
Andrew, my coil program might interest you. It calculates inductance and Q for solenoids made of solid or Litz wire. It models a number of wire alloys and form dielectrics, dielectric ribs or ridges, coil leads, and polygonal coil shapes. The program can automatically maximize coil Q while keeping inductance constant.
To validate accuracy, the documentation compares calculated values with hundreds of inductance and Q measurements made with an HP 4342A Q meter on dozens of coils of widely varying size and shape. For the coils from my own junk box, average error magnitude is 2% for inductance and 5% for Q.
The program runs in Windows and is free.
Brian
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Re: Inductor Q Measurement
Andrew,
NanoVNA-saver works fine on my Mac.
73
John
M0JBA
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On 12 Oct 2021, at 19:56, Andrew Kurtz via groups.io <adkurtz@...> wrote:
That program sounds wonderful! The only problem is that my computer is a Mac, and I bet it won¡¯t handle it. I know someone might say ¡°O just get Python and change XYZ while uploading ABC from Github¡.¡± and I might as well be listening to Greek. I have not yet succeeded in getting my nanoVNA data other than by hand-typing it into Excel because I can¡¯t get nanoVNAsaver to run. Any way to get your Coil program working on a Mac?
Andy
On Oct 11, 2021, at 7:00 PM, Brian Beezley <k6sti@...> wrote:
Andrew, my coil program might interest you. It calculates inductance and Q for solenoids made of solid or Litz wire. It models a number of wire alloys and form dielectrics, dielectric ribs or ridges, coil leads, and polygonal coil shapes. The program can automatically maximize coil Q while keeping inductance constant.
To validate accuracy, the documentation compares calculated values with hundreds of inductance and Q measurements made with an HP 4342A Q meter on dozens of coils of widely varying size and shape. For the coils from my own junk box, average error magnitude is 2% for inductance and 5% for Q.
The program runs in Windows and is free.
Brian
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Re: Inductor Q Measurement
Correct. Dave - W?LEV On Tue, Oct 12, 2021 at 7:00 PM Andrew Kurtz via groups.io <adkurtz= [email protected]> wrote: Sounds intriguing! I routinely find self-resonance and calculate
parasitic C from that. I see that I could take that R and calculate Q, but
the Q would be for a frequency far from a practical one, and thus that Q
would not relate to my coil when in use¡ Agree?
Andy
On Oct 12, 2021, at 11:15 AM, Gary Rondeau <grondeau@...> wrote:
Quick and dirty method... Just measure the self resonance of your coil. If you calibrate the nVNA to your fixture and then just run the S11
sweep up high enough on the coil, you will undoubtedly see a resonant
peak. At low frequency you can determine the inductor, L. (the nVNA saver
software will do this for you) The frequency of the peak tells you the self
resonant parasitic capacitance, C. From the magnitude of the the
resistance, R, measured at self resonance, and the calculated self resonant
impedance, Z=sqrt(L/C), then Q will be R/Z.
This procedure also shows you explicitly when parasitic capacitance becomes important -- which it often does!
-- *Dave - W?LEV* *Just Let Darwin Work*
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Re: Inductor Q Measurement
Sounds intriguing! I routinely find self-resonance and calculate parasitic C from that. I see that I could take that R and calculate Q, but the Q would be for a frequency far from a practical one, and thus that Q would not relate to my coil when in use¡ Agree?
Andy
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On Oct 12, 2021, at 11:15 AM, Gary Rondeau <grondeau@...> wrote:
Quick and dirty method... Just measure the self resonance of your coil. If you calibrate the nVNA to your fixture and then just run the S11 sweep up high enough on the coil, you will undoubtedly see a resonant peak. At low frequency you can determine the inductor, L. (the nVNA saver software will do this for you) The frequency of the peak tells you the self resonant parasitic capacitance, C. From the magnitude of the the resistance, R, measured at self resonance, and the calculated self resonant impedance, Z=sqrt(L/C), then Q will be R/Z.
This procedure also shows you explicitly when parasitic capacitance becomes important -- which it often does!
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Re: Inductor Q Measurement
You're fine with alligator clips at HF frequencies - especially the BC band for the crystal radio. Don't sweat it !! If your crystal radio operated much above 100 MHz, yes, the alligator or crocodile clips would be an issue. And if the Rs is not measured at the operating frequency it does not reflect skin effect. In your case, the top of the BC band is 1.7 MHz. Rs consists of both the purely resistive component of the conductors and, in addition, the increase in effective Rs due to skin effect which is a function of frequency. Bottom line: you're fine at BC band frequencies. Dave - W?LEV On Tue, Oct 12, 2021 at 6:20 PM Andrew Kurtz via groups.io <adkurtz= [email protected]> wrote: Yes, R cannot be < 0, but my interpretation is simply that the -2 is error
in some small number like, say 1 or 2 ohms. I will admit that many of you
experts talk about how you attach your DUT very carefully, solder it,
sometimes have to throw it away when done testing, and all this sounds
bizarre to a non-EE who is simply playing with crystal radio. My nanoVNA
attaches to my DUT via 2 alligator clips which are on little connectors
(BNC maybe?) which screw into the VNA. I recognize that I am accepting
error, even though I do my calibration at the same alligator clips, but
except for R, I am convinced that the error I am accepting is negligible
when my interest is 0.5 to 25 MHz, picking up AM signals. (I welcome any
insights if you think I am wrong.)
Andy
On Oct 12, 2021, at 10:05 AM, Jim Lux <jim@...> wrote:
On 10/12/21 6:05 AM, DougVL wrote:
On Mon, Oct 11, 2021 at 09:21 AM, Andrew Kurtz wrote:
R is quite low and may vary between -2 and 5 ohms.
That "-2" suggests to me that you're not actually reading 'Resistance' there. Resistance should be positive, but Reactance can be in negative
ohms.
Depending on how the conversion from reflection or transmission
coefficient (gamma) to R+jX is done, a coefficient with magnitude >1 will
result in negative R.
If you're measuring low impedances (so |gamma| is close to 1) then noise
or roundoff errors in a measurement can wind up with gamma>1
-- *Dave - W?LEV* *Just Let Darwin Work*
|
Re: Inductor Q Measurement
That program sounds wonderful! The only problem is that my computer is a Mac, and I bet it won¡¯t handle it. I know someone might say ¡°O just get Python and change XYZ while uploading ABC from Github¡.¡± and I might as well be listening to Greek. I have not yet succeeded in getting my nanoVNA data other than by hand-typing it into Excel because I can¡¯t get nanoVNAsaver to run. Any way to get your Coil program working on a Mac?
Andy
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Show quoted text
On Oct 11, 2021, at 7:00 PM, Brian Beezley <k6sti@...> wrote:
Andrew, my coil program might interest you. It calculates inductance and Q for solenoids made of solid or Litz wire. It models a number of wire alloys and form dielectrics, dielectric ribs or ridges, coil leads, and polygonal coil shapes. The program can automatically maximize coil Q while keeping inductance constant.
To validate accuracy, the documentation compares calculated values with hundreds of inductance and Q measurements made with an HP 4342A Q meter on dozens of coils of widely varying size and shape. For the coils from my own junk box, average error magnitude is 2% for inductance and 5% for Q.
The program runs in Windows and is free.
Brian
|
Re: suitable software to control full funcion NanoVNA
There are several programs - please browse the forum Wiki for information.
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On Tuesday, October 12, 2021, 02:17:10 p.m. EDT, Francesco <realfran@...> wrote:
Hello, there is one suitable PC software to control the full function of NanoVNA for windows?
73/Francesco
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Re: Inductor Q Measurement
Yes, that article and Alan¡¯s explanation were very helpful. I realize that I had a misunderstanding of where a ¡°parallel¡± resistor would be, and how a resonant circuit can be tested via shunt reflection versus transmission shunt through versus transmission series through. I had even gotten the impression that nanoVNAs really work best in reflection on CH0 only, not so much transmission from CH0 to CH1 even though that is available. For the record, I have been able to calculate that X / Rs = Rp / X exactly!
Andy
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On Oct 11, 2021, at 6:51 PM, Kerry <planningpower@...> wrote:
A useful article;
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Re: Inductor Q Measurement
On 10/12/21 11:20 AM, Andrew Kurtz via groups.io wrote: Yes, R cannot be < 0, but my interpretation is simply that the -2 is error in some small number like, say 1 or 2 ohms. exactly. Let's say the gamma measurement is +/- 5%.? If you convert gamma = 1.05 (angle = 0) you get -2050 ohms and Mag S11 = 0.4238 dB If you convert gamma=0.95, you get 1950 ohms and mag S11 = -.4455 dB Here's some examples (excel attached if you want to fool with it yourself).? For any coil with a reasonably high Q (>100), your DC resistance might be pretty low, especially if the reactance is something like 100 ohms.? In such a case, gamma is VERY close to 1, so small uncertainty in the measurement will result in negative resistance Z = Z0*(1+gamma)/(1-gamma) Z0 50 gamma mag gamma ang complex Z Zreal Zimag 0.5 0 0.5 150 150.0 0.0 0.5 90 3.06287113727155E-17+0.5i 30+40i 30.0 40.0 0.95 0 0.95 1950 1950.0 0.0 0.99 0 0.99 9950 9950.0 0.0 1 0 1 #NUM! #NUM! #NUM! 1.01 0 1.01 -10050 -10050.0 0.0 1.05 0 1.05 -2050 -2050.0 0.0 0.95 90 5.81945516081595E-17+0.95i 2.56241787122207+49.9342969776609i 2.6 49.9 0.99 90 6.06448485179767E-17+0.99i 0.50249987374375+49.9974748750063i 0.5 50.0 1 90 6.1257422745431E-17+i 50i 0.0 50.0 1.01 90 6.18699969728853E-17+1.01i -0.49750012375625+49.9975248750062i -0.5 50.0 1.05 90 6.43202938827026E-17+1.05i -2.43757431629014+49.9405469678954i -2.4 49.9 gamma = (Z-Z0)/(Z+Z0) R X Z Q gamma gamma mag gamma angle 0 500 500i #DIV/0! 0.98019801980198+0.198019801980198i 1.000 11.42 1 500 1+500i 500 0.97981005617555+0.197940625729906i 1.000 11.42 2 500 2+500i 250 0.979422565531214+0.197859946815246i 0.999 11.42 -1 500 -1+500i -500 0.980586447755754+0.198097471880064i 1.000 11.42 -2 500 -2+500i -250 0.980975331346312+0.198173631809246i 1.001 11.42 0 100 100i #DIV/0! 0.6+0.8i 1.000 53.13 1 100 1+100i 100 0.595270216649472+0.793587810491231i 0.992 53.13 2 100 2+100i 50 0.590680100755667+0.787153652392947i 0.984 53.12 -1 100 -1+100i -100 0.604870574953633+0.80638658172728i 1.008 53.13 -2 100 -2+100i -50 0.609882964889467+0.812743823146944i 1.016 53.12 I will admit that many of you experts talk about how you attach your DUT very carefully, solder it, sometimes have to throw it away when done testing, and all this sounds bizarre to a non-EE who is simply playing with crystal radio. My nanoVNA attaches to my DUT via 2 alligator clips which are on little connectors (BNC maybe?) which screw into the VNA. I recognize that I am accepting error, even though I do my calibration at the same alligator clips, but except for R, I am convinced that the error I am accepting is negligible when my interest is 0.5 to 25 MHz, picking up AM signals. (I welcome any insights if you think I am wrong.)
Andy
On Oct 12, 2021, at 10:05 AM, Jim Lux <jim@...> wrote:
On 10/12/21 6:05 AM, DougVL wrote:
On Mon, Oct 11, 2021 at 09:21 AM, Andrew Kurtz wrote:
R is quite low and may vary between -2 and 5 ohms.
That "-2" suggests to me that you're not actually reading 'Resistance' there. Resistance should be positive, but Reactance can be in negative ohms. Depending on how the conversion from reflection or transmission coefficient (gamma) to R+jX is done, a coefficient with magnitude >1 will result in negative R.
If you're measuring low impedances (so |gamma| is close to 1) then noise or roundoff errors in a measurement can wind up with gamma>1
|
Re: Inductor Q Measurement
Yes, R cannot be < 0, but my interpretation is simply that the -2 is error in some small number like, say 1 or 2 ohms. I will admit that many of you experts talk about how you attach your DUT very carefully, solder it, sometimes have to throw it away when done testing, and all this sounds bizarre to a non-EE who is simply playing with crystal radio. My nanoVNA attaches to my DUT via 2 alligator clips which are on little connectors (BNC maybe?) which screw into the VNA. I recognize that I am accepting error, even though I do my calibration at the same alligator clips, but except for R, I am convinced that the error I am accepting is negligible when my interest is 0.5 to 25 MHz, picking up AM signals. (I welcome any insights if you think I am wrong.)
Andy
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On Oct 12, 2021, at 10:05 AM, Jim Lux <jim@...> wrote:
On 10/12/21 6:05 AM, DougVL wrote:
On Mon, Oct 11, 2021 at 09:21 AM, Andrew Kurtz wrote:
R is quite low and may vary between -2 and 5 ohms.
That "-2" suggests to me that you're not actually reading 'Resistance' there. Resistance should be positive, but Reactance can be in negative ohms. Depending on how the conversion from reflection or transmission coefficient (gamma) to R+jX is done, a coefficient with magnitude >1 will result in negative R.
If you're measuring low impedances (so |gamma| is close to 1) then noise or roundoff errors in a measurement can wind up with gamma>1
|
suitable software to control full funcion NanoVNA
Hello, there is one suitable PC software to control the full function of NanoVNA for windows?
73/Francesco
|
Re: Inductor Q Measurement
Bill, I'm not sure this does what you want, but try it: Set frequency, coil diameter, and wire gauge. Click on Turns for turns/inch and set the value you have in mind. Then vary coil length with the mouse wheel until you get the desired inductance. It's really fast if it's what you need. The only thing I truly automated was Q optimization.
Brian
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Re: Inductor Q Measurement
Gary,
Have you evaluated the Q at OR near the SRF and then the Q significantly below SRF?
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It's not the backlight current as it runs off the 5v line, not the 5V-RF or the 3V sources.
Since the unit is new, it's most likely infant-mortality on the part or a counterfeit part was used that was mislabelled as a higher current device when in fact it wasn't. Lots of that in China, unfortunately.
Yes - claim a replacement. If they tell you to keep the old one, you can source 3V LDO devices from old scrap home wifi routers and access points as they all use 3v parts.
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On Tuesday, October 12, 2021, 12:43:55 p.m. EDT, cube1us <cube1@...> wrote: As a guess, a thermal issue? 73 JRJ? WIYN On 10/12/2021 7:33 AM, Jens M?ller wrote: Hello Larry,
Thank you for your reply.
No that doesn't help.
Am 12.10.2021 um 13:47 schrieb Larry Rothman:
? If you immediately cycle the power off then on, does the unit start
running ok again?
???? On Tuesday, October 12, 2021, 04:57:52 a.m. EDT, <df9hj@...>
wrote:
? Hi All,
While running NanoVNA H4 with Nano saver via USB abt? 1 hour the
NanoVNA H4 screen gets blank.
The NanoVNA H4 desn't reboot, USB connection is also lost, only blue
LED beside the mini USB is blinking whlie charging and steady when
fully chared.
Any hints?
Thanks folks
vy 73 Jens DF9HJ
|
Re: Inductor Q Measurement
Hi Brian,
Thanks for reminding all about COIL. It takes a little getting familiar with it since you use an interesting GUI interface, but I got the handle on it.?
Is there a way to input the coil inductance, fix the physical parameters and come up with the required turns. It didn't seem like it. It's still very useful - thanks again.
Regards...Bill - N6GHz
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On 10/12/2021 05:47:39, Brian Beezley <k6sti@...> wrote:
Thanks for the feedback, Dave. I didn't mention that COIL is a Windows console program. I gather that wineconsole is necessary. I forgot to mention that a user should first read README.TXT. COIL evolved from a DOS program I wrote 25 years ago. It does not have the usual Windows user interface. Many features are inscrutable, but they are explained in the documentation.
Brian
|
As a guess, a thermal issue?
73 JRJ WIYN
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On 10/12/2021 7:33 AM, Jens M?ller wrote: Hello Larry,
Thank you for your reply.
No that doesn't help.
Am 12.10.2021 um 13:47 schrieb Larry Rothman:
? If you immediately cycle the power off then on, does the unit start running ok again?
???? On Tuesday, October 12, 2021, 04:57:52 a.m. EDT, <df9hj@...> wrote:
? Hi All,
While running NanoVNA H4 with Nano saver via USB abt? 1 hour the NanoVNA H4 screen gets blank.
The NanoVNA H4 desn't reboot, USB connection is also lost, only blue LED beside the mini USB is blinking whlie charging and steady when fully chared.
Any hints?
Thanks folks
vy 73 Jens DF9HJ
|
Thanks,
It looks like the LD01 is defective as only 1V is coming out instead of 3V.
I didn't expect to have a defective unit as I posses it only 2 weeks.
I'll claim for a replacement rather than chaning the regulator.
Anyhow thanks for help.
Am 12.10.2021 um 16:10 schrieb Larry Rothman:
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Well, it appears you have some type of hardware failure..
if you reconnect the battery, measure the voltage at the power SW with the USB cable disconnected - it should be 5V.
Turn ON and? measure the voltage at the 3V LDO1 regulator in and out (see schematic image). In=5V, VDD out =3V (at edge of PCB beside the Boot-0 pin)
Measure 5V out of IC 3
Refer to the photo of the H4 board here:
/g/nanovna-users/photo/0/34671.24755.1?p=Created%2C%2C%2C20%2C2%2C20%2C0
It's really just standard troubleshooting at this point, unfortunately.
BTW - when you turn the unit ON and it is disconnected from USB, is the LED flashing?
On Tuesday, October 12, 2021, 09:48:42 a.m. EDT, Jens M?ller <df9hj@...> wrote:
Disconnected battery still doesn't power up at usb only.
Am 12.10.2021 um 15:11 schrieb Larry Rothman:
? So, your nano is now no longer working at all even after letting it stay off for a while?If you open the housing and remove the battery, see if you can power the unit only from USB. If yes, then the charging/inverter IC may have failed.
? ? ? On Tuesday, October 12, 2021, 08:34:00 a.m. EDT, Jens M?ller <df9hj@...> wrote:
? Hello Larry,
Thank you for your reply.
No that doesn't help.
Am 12.10.2021 um 13:47 schrieb Larry Rothman:
? ? If you immediately cycle the power off then on, does the unit start running ok again?
? ? ? ? On Tuesday, October 12, 2021, 04:57:52 a.m. EDT, <df9hj@...> wrote:
? ? Hi All,
While running NanoVNA H4 with Nano saver via USB abt? 1 hour the NanoVNA H4 screen gets blank.
The NanoVNA H4 desn't reboot, USB connection is also lost, only blue LED beside the mini USB is blinking whlie charging and steady when fully chared.
Any hints?
Thanks folks
vy 73 Jens DF9HJ
|
Re: Inductor Q Measurement
Quick and dirty method... Just measure the self resonance of your coil. If you calibrate the nVNA to your fixture and then just run the S11 sweep up high enough on the coil, you will undoubtedly see a resonant peak. At low frequency you can determine the inductor, L. (the nVNA saver software will do this for you) The frequency of the peak tells you the self resonant parasitic capacitance, C. From the magnitude of the the resistance, R, measured at self resonance, and the calculated self resonant impedance, Z=sqrt(L/C), then Q will be R/Z.
This procedure also shows you explicitly when parasitic capacitance becomes important -- which it often does!
|
Re: Inductor Q Measurement
Brian, thanks for the background information on COIL I have gotten many
features to work under Wine in Linux and it is very useful. I may have
spoken a bit too soon in implying everything would work with Wine. However,
I need to brush up on Wine and to try COILS on a Windows machine to see
what I may be missing. Thanks again!
Dave
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On Tue, Oct 12, 2021 at 8:47 AM Brian Beezley <k6sti@...> wrote: Thanks for the feedback, Dave. I didn't mention that COIL is a Windows
console program. I gather that wineconsole is necessary. I forgot to
mention that a user should first read README.TXT. COIL evolved from a DOS
program I wrote 25 years ago. It does not have the usual Windows user
interface. Many features are inscrutable, but they are explained in the
documentation.
Brian
|
Well, it appears you have some type of hardware failure.. if you reconnect the battery, measure the voltage at the power SW with the USB cable disconnected - it should be 5V. Turn ON and? measure the voltage at the 3V LDO1 regulator in and out (see schematic image). In=5V, VDD out =3V (at edge of PCB beside the Boot-0 pin) Measure 5V out of IC 3 Refer to the photo of the H4 board here: /g/nanovna-users/photo/0/34671.24755.1?p=Created%2C%2C%2C20%2C2%2C20%2C0It's really just standard troubleshooting at this point, unfortunately. BTW - when you turn the unit ON and it is disconnected from USB, is the LED flashing?
On Tuesday, October 12, 2021, 09:48:42 a.m. EDT, Jens M?ller <df9hj@...> wrote: Disconnected battery still doesn't power up at usb only. Am 12.10.2021 um 15:11 schrieb Larry Rothman: ? So, your nano is now no longer working at all even after letting it stay off for a while?If you open the housing and remove the battery, see if you can power the unit only from USB. If yes, then the charging/inverter IC may have failed.
? ? ? On Tuesday, October 12, 2021, 08:34:00 a.m. EDT, Jens M?ller <df9hj@...> wrote:
?
? Hello Larry,
Thank you for your reply.
No that doesn't help.
Am 12.10.2021 um 13:47 schrieb Larry Rothman:
? ? If you immediately cycle the power off then on, does the unit start running ok again?
? ? ? ? On Tuesday, October 12, 2021, 04:57:52 a.m. EDT, <df9hj@...> wrote:
? ?
? ? Hi All,
? ?
While running NanoVNA H4 with Nano saver via USB abt? 1 hour the NanoVNA H4 screen gets blank.
The NanoVNA H4 desn't reboot, USB connection is also lost, only blue LED beside the mini USB is blinking whlie charging and steady when fully chared.
Any hints?
Thanks folks
vy 73 Jens DF9HJ
? ? ?
? ?
|
Francesco
cube1us
