Пікірлер
@paps.bricole
@paps.bricole 5 күн бұрын
Merci pour ce comparatif, hyper intéressant ! ;)
@yTb2801082331
@yTb2801082331 Ай бұрын
Very interesting and clear! Thank you very much (for the utility gnuplot too !!! )
@electronics.unmessed
@electronics.unmessed Ай бұрын
Very comprehensive and interesting. Thx for sharing!
@stevenwilliams6258
@stevenwilliams6258 3 ай бұрын
Interesting and informative review! I don't do RF work but find this equipment interesting. I studied books in the 70's to get a first class FCC license but haven't ever used that in work. This review and that on the TinySA show that this technology can be obtained for a reasonable cost for schools and hobbyists. I got the TinySA just for kicks but not sure what I would do with the VNA. Thanks for two well done videos. I know it takes lots of time and effort.
@showmytime9177
@showmytime9177 3 ай бұрын
one of the "pussyble" ... LMAO =)
@ruwan23boy
@ruwan23boy 4 ай бұрын
What type of oil should I use?
@the_bootloader
@the_bootloader 4 ай бұрын
It really depends what's available to you. Regular 3-in-1 motor oil is fine. Or light machine oil (same as in sewing machines). 20w or 30w oil can work too. It's not really critical as long as it's oil and that it's low viscosity.
@ruwan23boy
@ruwan23boy 4 ай бұрын
@@the_bootloader thank you so much
@Wil_Bloodworth
@Wil_Bloodworth 4 ай бұрын
This is a great tip! It does not work for measuring DC and AC at the same time though... as far as I can tell.
@deanriver9388
@deanriver9388 5 ай бұрын
Just put a new motor in.
@sankarmajhi8276
@sankarmajhi8276 5 ай бұрын
Can I measure temperature and dc voltage at the same time ?
@KonstantinosKalleris
@KonstantinosKalleris 5 ай бұрын
Thank you for the range tip. I hadn't realized that. A tip from me is that you can meassure the current on the low side of the load. By this way you will able to measure the voltage correctly on the high side. Thank you for the video. Kostas
@FinepixF30
@FinepixF30 5 ай бұрын
8:01 As far as i know induction motors speed can change based on the alternating current frequency or the number of poles, with the windings you might be changing the number of poles, the draw back is it lowers the torque and cause over heating of the motor. is better to leave the wiring to what the manufacturers set it to.
@nancyzehr3679
@nancyzehr3679 5 ай бұрын
you didnt turn the gas back on!
@rilosvideos877
@rilosvideos877 6 ай бұрын
Good review and very important points! The problem is you never know what you get when you buy cheap of of china/ebay/aliexpress... Even when one version was tested good, they build new fakes and it gets worse - but you don't know unless you have the capability to really test your device properly. Thanks a lot!
@sidlinger
@sidlinger 6 ай бұрын
Very helpful! Thank you!
@SQ5DBF
@SQ5DBF 7 ай бұрын
Hello. I'v also designed time base for counter JDS6600.
@ernestb.2377
@ernestb.2377 7 ай бұрын
Nice to see the comparison. I have nanoVNA-H4 from a reputable seller in The Netherlands and i suppose it is not a clone. The enclosure is a 'snap-on' type, so not easy to open up and look inside and say something about the shielding. I also don't have another instrument at home to compare, but could ask my colleague at work to do a quick compare. I have done some basic measurement filter measurements and on my EFHW 10m long antenna and could fine tune it with this nanoVNA. It all seems right, but once again not much to compare yet. About the port 21 isolation graph, that could be calibrated away? Or not?
@ernestb.2377
@ernestb.2377 4 ай бұрын
Edit: nonsense what I said about the enclosure 🙈 it has 4 screws.
@michaelmdy
@michaelmdy 7 ай бұрын
Have you or anyone else taken the next step to hack and integrate with an ESP8266 to allow for Alexa control?
@tcarney57
@tcarney57 7 ай бұрын
Many thanks. This was a very interesting set of tests. Based on my own needs, my take away is that all three VNAs are very close to each other up to 400 or 500MHz and then they diverge, the "H" clone sharply so. Everything I do, though, is below 148MHz, and within that larger range usually test in much smaller spans of 10KHz or so and once in a while 200 or 300KHz. All below 148MHz. Any of these--the two nanoVNAs or the Siglent--would be adequate for my purposes. The 10 and 20dB offsets produced by the H-clone is weird. I wonder if the very-wide bandwidth scanned in these tests has anything to do with that
@JohnUsp
@JohnUsp 8 ай бұрын
Not ceramic fuse?! argh...
@firasgh871
@firasgh871 8 ай бұрын
شكرا على الفيديو.سؤالي ما مدى اختلاف القياسات أن وضعنا أكثر من مقياس من نفس النوع بقراءة الجهد والتيار !
@robertmckay8467
@robertmckay8467 8 ай бұрын
I wonder if the low battery alarm also goes out over the network?
@dalesmith8666
@dalesmith8666 9 ай бұрын
The best is...., a HP8753E, ya it cost money, then again, if you want to go down the 1/4 mile track in 7 seconds, your not going to do it with a 4 banger, Datsun! LOL!@
@davidmotley4207
@davidmotley4207 10 ай бұрын
You mentioned bearing. Your motor is not a bearing type, it is a bushing and it needs oiling.
@the_bootloader
@the_bootloader 10 ай бұрын
This is correct - oiling this bushing is what this video is all about. English not being my native language, I may very well have used the wrong word. I hope that you have still found the video helpful.
@firasgh871
@firasgh871 10 ай бұрын
اتمنى الحصول ببلدي على اجهزة قياس حديثة سوأ حظي بلدنا انهكته الحروب بسوريا . لكن بما انه مضى 2 سنة على نشرك الفيديو هل مازلت تستخدمه بشكل جيد
@tommoran2113
@tommoran2113 11 ай бұрын
Thank You, I had a noisy motor, it got hot and I followed your instructions and reoiled!!! Back up and running, smooth and quiet now.
@WillBeHere2013
@WillBeHere2013 11 ай бұрын
I too am in the middle of my replacement cycle. Thanks for making the video. Great use for your old detectors.
@danielrioux54
@danielrioux54 11 ай бұрын
Why not try the LibreVNA ?
@uni-byte
@uni-byte 11 ай бұрын
Nice upgrade!
@aymanjundi7540
@aymanjundi7540 11 ай бұрын
Hi there, i discovered your channel by mere coincidence, great content...keep up the good work👍 but i was wondering about your shielding, the 1st one in particular, aren't you changing the microstrip impedance by adding an extra layer of ground above it? try to change the height of the shield to see if it affects the readings to confirm this theory, maybe you can try not to ground the shields 😶‍🌫? i also suspect that the usb connection might affect things here( grounding issues?) i would really like to see the results, it would be fun and educational to find the culprit or to confirm that it's a bad PCB layout issue. Merci beaucoup et bon courage pour la suite😉
@JAKOB1977
@JAKOB1977 Жыл бұрын
stay under 300MHz, its a 30 buck clone product, tripping on harmonics in the GHz range, and expecting reference values. use it in its range to a frew hundred MHz and here it would have been relevant to see how it performed vs its price.
@the_bootloader
@the_bootloader Жыл бұрын
When evaluating a product, it is always useful to evaluate it beyond its capabilities, to know up to where they may extend. There are many products that can do better than they should - and as a matter of fact, it is still a useful product beyond 300MHz. We just have to manage expectations. I hope that this video helped do that. Thank you for watching and commenting!
@Erik.Henneberg
@Erik.Henneberg Жыл бұрын
I like the design for the PM6666 ocxo and would like to ask if you have a PCB leftover ( if gerber files are available I would very much appreciate it !) ? br Erik from Denmark
@hugopristauz3620
@hugopristauz3620 Жыл бұрын
very helpful 🙂
@brucetouzel6484
@brucetouzel6484 Жыл бұрын
can you mirror the DMM6500 display onto a monitor by simply using a USB to HDMI adaptor ?
@ЖивойАнеСуществующий
@ЖивойАнеСуществующий Жыл бұрын
Does this multimeter reset calibration if the battery runs out? (CR 2032?) Is this really true??? And will it need to be carried to a special laboratory for accurate calibration? Is it somehow possible to calibrate this device without a lab? Is it possible to somehow enter data (calibrate) the wires (probes)? (Let's say I bought other wires and want to account for the capacitance/resistance etc of the new wires)
@whatthe2458
@whatthe2458 Жыл бұрын
Is there such a thing as a 5V transformer? In other words, can you downgrade the transformer you have to something smaller like a 5v ?
@the_bootloader
@the_bootloader Жыл бұрын
Yes, you need a DC/DC converter (or AC/DC if you have alternative current, such as in my case in this video) of the suitable specifications (input voltage range, desired output voltage, and with sufficient of output current capability)
@superalpha
@superalpha Жыл бұрын
Although it is doubtful that shielding is the solution for the problem, you should try with a shield tape that has high permeability. I used to have an RF shielding tape kit that had all kinds of options, but you can't get that kit anymore.
@digitalradiohacker
@digitalradiohacker Жыл бұрын
When you take measurements from duplexers, put a dummy load on the unused port. Leaving the unused port floating ussually results in phantom troughs all over the place.
@the_bootloader
@the_bootloader Жыл бұрын
I had to recheck the video and you're right, I totally forgot to do it. I believe the impact shouldn't be very significant due to the attenuation between the channels, but you're absolutely correct, this is an oversight on my part during this test. Thanks for pointing it out!
@digitalradiohacker
@digitalradiohacker Жыл бұрын
@@the_bootloader For what you were doing, I guess you could choose to deliberately ignore wierd responses outside of the band of interest. The only reason I noticed was because I have to tune commercial duplexers at work, and the phantom troughs can cause serious issues with figuring out what is going on.
@the_bootloader
@the_bootloader Жыл бұрын
@@digitalradiohacker yes you're absolutely right. As you point out, for my purpose it didn't really matter but generally it's good practice and the way to do it. Thanks again for participating and sharing your knowledge, it's great that we can all learn together from our respective experiences
@digitalradiohacker
@digitalradiohacker Жыл бұрын
@@the_bootloader Absolutely. I bought one of these as a potential alternative to the 10KG Aeroflex 3500 that I have in my van. I know that a new instrument of this class costs the same as a house, so they're not the same, but there is also 20 years of development between them as well. In reality, I'm finding the noise floor on mine to be quite pathetic (around 50dB?). This is no good for tuning commercial duplexers which are capable of -80dB rejection. Mine is marked as NanoVNA-H The search for firmware that won't make a brick is ongoing.....
@ezyjack826
@ezyjack826 Жыл бұрын
replacing blower motor on my furnace. problem is it's an old unit (pre 1988) and they have updated the motor. the new motor has 4 wires plus the 2 capacitor wires and the original motor had 5 wires plus the 2 capacitor wires. the difference according to the motor tag is the original motor had two med speeds and the new motor only has one med speed. can I wire it up with one med speed? do I use med lo wire, med hi wire or both med to the new motor? ty for any assistance you can provide. 🙂
@the_bootloader
@the_bootloader Жыл бұрын
Hi! Unfortunately it is very hard for me to give you a precise answer without seeing the motor and the furnace. That said, I can give general tips. First, you need to go not by the name of the speed (lo/med/high) but by the actual RPM speed written on the motor. For instance if you were using the med low speed before, and that speed was 1500 RPM, you need to check which speed on the new motor is 1500 RPM. It could be the med speed but could also be the low or high speed. You also need to understand what triggered the speed change on the previous motor, if anything. Sometimes, furnaces use different speeds. Sometimes they use just one. You need to restore this behavior. For many single-stage and heat-only furnaces, only one speed is used. If you have both cooling and heating, different speeds may be used. If unsure, you should call a pro because you risk burning your motor or causing other dangerous conditions. Stay safe and I hope this is helpful!
@stargazer7644
@stargazer7644 Жыл бұрын
Just plug a GPSDO into the external ref jack. Far easier and more accurate.
@the_bootloader
@the_bootloader Жыл бұрын
Depends of the situation. Right now, in my lab, I can't have satellite reception, and I can't install an antenna on the roof either. Having the capability to have an OCXO in my instruments, that I can calibrate once a year or so, is perfect. It gives me more precision than I realistically need. Of course, everyone's situation and needs are different. Thanks for watching!
@stargazer7644
@stargazer7644 Жыл бұрын
@@the_bootloader While an outside antenna is always best, once a GPSDO's location is set, it only needs one satellite to stay phase locked. GPS receivers are very sensitive now, and some will track multiple GNSS constellations. Mine works just fine inside the house through the floor above and the roof. It looks like your lab has a window. As long as there isn't metal film on the glass, a GPS receiver will usually work fine looking out the window. If you're in a multi-story concrete building with tinted windows and no balcony, you may have a problem. Good luck!
@the_bootloader
@the_bootloader Жыл бұрын
@@stargazer7644 Thanks! All good points. Unfortunately I am in a multistory townhome, and the lab is on the ground floor
@blueduck9409
@blueduck9409 Жыл бұрын
Thank you for sharing this video.
@the_bootloader
@the_bootloader Жыл бұрын
You're welcome, happy it helped
@DarkoObretan
@DarkoObretan Жыл бұрын
As Andy mentioned DDS are different in you VNAs. That is very important, because RF generator output power is much lower when using 2nd harmonic and even lower when using 3rd harmonic, and if we say RX sensitivity and noise stays the same, you get much worse S/N ratio (you get more noise compared to the signal) on higher frequencies. Shielding would help, but just to a point. When you calibrate VNA it offsets that very low (2nd or up to 5th harmonic) signal level with big gain to get 0dB trace at all frequencies, so it is mostly RF generator output level problem. RX sensitivity is also getting worse at higher frequencies, because of higher mixer conversion losses, which is another 'RF signal level' problem. Inconsistencies between measurements are also due to cable bending (since those cables are not phase stable), SMA tightening and some common mode current outside the coax. It would be interesting to take one measurement with Siglent, then disconnect cable, connect it again to Siglent and taking second measurement. I suspect you would get almost the same difference as you did with comparison to SAA2. That would show cable bending and SMA tightening contributions plus other measurement uncertainties.
@davidaz4933
@davidaz4933 Жыл бұрын
good job . I recommend you add to the v reg circuit add a bypass diode between the VIN and VOUT terminals of the reg (reverse-current bypass diode) This is standard in Liner Voltage Regulators design
@the_bootloader
@the_bootloader Жыл бұрын
Thanks for the suggestion. The main power supply uses a switching regulator module. The other "power supply" is a voltage reference, and as such it should not see any reverse current. Which regulator were you thinking about? But you are right, when dealing with LDOs, adding a reverse-current bypass diode is good practice!
@davidaz4933
@davidaz4933 Жыл бұрын
@@the_bootloader I usually use LDO of Linar Technology current source based example LT3083 LT3042 But this method is most useful for Basic V REG 78XX I use low noise LDOs Because I build a lot of V REF circuits Linar Technology makes the best regulator there is
@AKkarol7
@AKkarol7 Жыл бұрын
Great video. Can you make a video on upgrading the SSA3021x to SVA1032x ?
@blackarrow8683
@blackarrow8683 Жыл бұрын
Thank you for uploading more often! Really loving your videos. Maybe a suggestion for the future: The graph colors in the legends looks all black. It is impossible to read which graph should be which color in the legend. Maybe make the legend graph lines a bit bigger, so you can see which color is which. Thanks 🥰
@the_bootloader
@the_bootloader Жыл бұрын
Thanks! I apologize for that, I noticed it too. They were fine in the video before I uploaded it, I guess the colors went *poof* when KZbin recompressed the video.
@andymouse
@andymouse Жыл бұрын
Fascinating...cheers.
@rjordans
@rjordans Жыл бұрын
For the data processing I found exporting the s1p or s2p files and using Python with scikit-rf a nice tool too
@the_bootloader
@the_bootloader Жыл бұрын
Good suggestion, thanks for sharing! I may give it a try
@andylawton2638
@andylawton2638 Жыл бұрын
The SAA2 VNA uses a different DDS to the NanoVNA. The NanoVNA uses a SI5351 which can only generate frequencies up to 300MHz and uses harmonics to get above it. This reduced dynamic range significantly. The SAA2 uses an ADF4351 which can generate RF up to 4.4GHz without resorting to using harmonics, resulting in a better dynamic range across the board. Newer SAA2 revisions use the MAX2871 which is very similar to the ADF4351 but can sweep up to 6GHz. As you say, the shielding will also help with the SAA2. I also own a NanoVNA, one of the original SAA2 VNAs and a Siglent VNA :-)
@galileo_rs
@galileo_rs Жыл бұрын
The white Nano is a clone and the results you are getting are probably due to that fact. I have a modified clone H and an original H4 and those do not exhibit that kind of behaviour. Try NanoVNA Saver software and do not calibrate on device. Saver will offer much higher number of calibration points and a correction for the trough measurement. Makes sure that you get the latest firmware. DisLord firmware is recommended.
@hinz1
@hinz1 Жыл бұрын
NanoVNA-H is the old V1 version, Si5335 based, that works on harmonics above something like 300MHz, so no wonder it has much worse specs. Si5335 synthesizer chip official spec: fmax 200MHz NanoVNA V2 is new version based on 2x ADF4350 with official fmax of 4400Mhz, so no harmonics needed. NanoVNA-F V2 clone version with somewhat better/nicer mechanical design, aluminum case instead of plastics, for a bit more money
@germanjohn5626
@germanjohn5626 Жыл бұрын
I wonder why people always insist to compare a basic toy like tool to a semi professional one. It is like comparing a Cozy Coupe to a mid size Chevy or Volkswagen.
@the_bootloader
@the_bootloader Жыл бұрын
The SAA2 performing on par with the Siglent, at least on a noise level perspective up to 1.5GHz, was unexpected. There are other valuable pieces of information shared, such as a methodology to graph data from multiple brands of VNAs. Thank you for watching and for your feedback
@galileo_rs
@galileo_rs Жыл бұрын
Nano is not (especialy the official versions) a toy up to 250MHz.
@solarflare4259
@solarflare4259 Жыл бұрын
Most of the people will use the nanoVNA way below GHz frequency so it performs great!My '97 Golf still runs like a swiss watch and takes me to places while seeing many luxury cars biting the dust...:) It gets the job done...:)
@galileo_rs
@galileo_rs Жыл бұрын
@@solarflare4259 True. There are other version of Nano that are fine in the GHz range, LiteVNA for example (same manufacturer as for H4), and pretty affordable. Golf bit reminds me of the Balkans 😁
@solarflare4259
@solarflare4259 Жыл бұрын
@@galileo_rs Indeed. I've got a H4 and it works great. I find myself using it up to 60 MHz, mostly for HAM shortwave...Currently waiting to receive the 4401 ... Just wanted a larger display. As for the Golf, I grabbed it back in '99 and I've taken good care of it.It comes really handy now with rising of fuel prices (2L) engine MT... I barely see some like these on the road; even hard to find parts at salvage yards...:)