WOW!??
Go to your local mobile phone shop/kiosk and just buy a thin/low-profile replacement battery and use that - like I did with my first Gecko Nanovna.
I used a small nut as a spacer under each screw to move the rear panel enough for the 800mAH phone battery to fit.
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On Wednesday, November 20, 2019, 2:47:08 p.m. GMT-5, erik@... <erik@...> wrote: The battery was already swollen when I got the nanoVNA. It is now even more swollen. Only used computer USB2.0 ports to charge, not even USB3.0. Never a separate charger Will contact hugen as I bought from his shop and the battery is glued to the PCB and I do not want to destroy my nanoVNA -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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Only if you fear fire and explosions.
Glenn
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On 11/20/2019 2:14 PM, erik@... wrote: On Wed, Nov 20, 2019 at 08:11 AM, Larry Rothman wrote:
Please DO NOT USE any LiIon battery that is beginning to swell !!!
Should I be worried?
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Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"
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On Mon, 18 Nov 2019 at 13:58, RFy <gpdxdveil@...> wrote: 450mAh is... Not suitable for NanoVNA
1. Stand-by draw
2. Charge circuit pushes over 1A( over 2C rate )
My battery already swelled( PCB/LCD curved slightly ) There are some high specification batteries for sale on eBay, at quite a reasonable cost. Dave. -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom
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The battery was already swollen when I got the nanoVNA. It is now even more swollen. Only used computer USB2.0 ports to charge, not even USB3.0. Never a separate charger Will contact hugen as I bought from his shop and the battery is glued to the PCB and I do not want to destroy my nanoVNA -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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For the forum members that are unsure of the safety when charging their Nanos, try to obtain a low-current PolyFuse and place it in series with the positive lead on the battery.
You can find info on Polyfuses here:?
I was looking up specs and found this part series that 'should' probably be OK to use as protection.
I attached the datasheet.
NOTE - these devices are used in most modern battery-powered electroinc devices so go through your junk box to see if there might be anything similar you can use.
On the other hand, stick a 22 to 27 ohm resistor in series with the battery to limit the current.
Cheers,??
Larry
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On Wednesday, November 20, 2019, 1:37:42 p.m. GMT-5, Andy via Groups.Io <punkbiscuit@...> wrote:
OK I started testing the charging current on my NVNA.
Typically 650ma on an empty 400ma supplied cell, oh dear !!!
I wasn't expecting that to be honest, I really did assume that there would be some controller regulating the current.
I consider that the IP5303 datasheet to be a bit misleading in my opinion.
Before I did the test, I also measure the current on a supposedly charged cell, and it wasn't actually any different.
Guess I'll be modding mine for an 18650 cell shortly.
Has anyone got a fire extinguisher that they can lend me ;)
73 de Andy
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Erik,
You really do not want to screw around with a swollen LiIon or generally any Lithium type battery that is beginning to swell.
All they are good for is taking them outside in a wide open area, banging a nail through and running up-wind of the smoke and fumes! ;-)
But seriously, working in a two-way radio service shop, I come across all shapes and sizes of batteries and we have to bag each Lithium unit that is recycled in order to prevent shorts to other devices.
Why take a chance on a fire. Lithium reacts to air AND water.
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On Wednesday, November 20, 2019, 2:14:13 p.m. GMT-5, <erik@...> wrote: On Wed, Nov 20, 2019 at 08:11 AM, Larry Rothman wrote:
Please DO NOT USE any LiIon battery that is beginning to swell !!!
Should I be worried? -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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Should I be worried? Not seen a swollen cell catch fie ...yet, but it is rumoured. More likely to cause physical damage to the VNA, or leak nasty stuff that yu might not want to get on your skin or inhale. It should should really be removed asap. 73 de Andy
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Re: errors of "error" models
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OK I started testing the charging current on my NVNA.
Typically 650ma on an empty 400ma supplied cell, oh dear !!!
I wasn't expecting that to be honest, I really did assume that there would be some controller regulating the current.
I consider that the IP5303 datasheet to be a bit misleading in my opinion.
Before I did the test, I also measure the current on a supposedly charged cell, and it wasn't actually any different.
Guess I'll be modding mine for an 18650 cell shortly.
Has anyone got a fire extinguisher that they can lend me ;)
73 de Andy
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Re: sensitivity (instability)
Tnx Alan
This morning I made new cables with rg142 and I think the double sheild helped a lot...
once again tnx and I am getting happier more I discover those little wonders!
Richard
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Well, no surprise. It was a scammer. Got Ebay refund yesterday.
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Please DO NOT USE any LiIon battery that is beginning to swell !!!? Recycle it.Once a LiIon battery is starting to swell, its internal chemistry is unstable.
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On Wednesday, November 20, 2019, 10:27:54 a.m. GMT-5, KV5R <kv5r@...> wrote:
I figured it out! After earlier posting, I remembered I have a wall charger for those Galaxy S3 batteries; it uses contacts 1 & 3.
And then reading the label on one of them, remembered the NFC antenna. Verified with the bench DMM.
With the battery oriented contacts up and left, and calling leftmost contact #1:
1. DC +
2. NFC loop antenna (2.4k-ohms to #3, either polarity)
3. DC - , and other end of NFC loop antenna
4. n/c (resistance infinite, either polarity)
So I'll take the oldest one (just beginning to swell) and try to solder #30 wires, hopefully without melting the plastic case too much...
Gotta order some 2.5mm standoffs first.
Thanks Guys,
73, --kv5r
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Re: sensitivity (instability)
I assume the YES is the answer to an antenna is under test. if the antenna physical dimension is not much larger than the vna and not current de coupled from the port, than the vna is part of the measurement system under test. The port Z will change as a consequence.
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I figured it out! After earlier posting, I remembered I have a wall charger for those Galaxy S3 batteries; it uses contacts 1 & 3.
And then reading the label on one of them, remembered the NFC antenna. Verified with the bench DMM.
With the battery oriented contacts up and left, and calling leftmost contact #1:
1. DC +
2. NFC loop antenna (2.4k-ohms to #3, either polarity)
3. DC - , and other end of NFC loop antenna
4. n/c (resistance infinite, either polarity)
So I'll take the oldest one (just beginning to swell) and try to solder #30 wires, hopefully without melting the plastic case too much...
Gotta order some 2.5mm standoffs first.
Thanks Guys,
73, --kv5r
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Sorry if this has been asked before but I mistakenly posted this in the NanoVNA-F group instead of this one.
Has anyone thought of implementing port extension functionality with on the fly adjustability like "real" network analyzers while on the instrument as well as the nanovna saver software?
The HP ones that I have used have an adjustment where you can simply increment the delay +/- with the 'wheelie" knob rather than input a discrete number (although you can if you want).
This makes it really simple to compensate for a fixture or a cable to quickly and easily move the reference plane.
Sam
W3OHM
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I suppose one way of seeing how the charging system works is to use an inline
USB meter like this
I don't mind sacrificing my own cell for this test,so when it's empty I'll do a test
and see what happens ;-)
73 de Andy
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Re: sensitivity (instability)
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Re: sensitivity (instability)
So did you ever notice that the reading of S11 is pertubated if you touch or
not the nanovna. even if the nanovna is on the table
and my hand get close to the vna there is fluctuation in the reading My unshielded "worse" clone is quite immune to proximity effects. In fact, the only time it became a problem was an SMA cable gone defective, presumably a poor crimp between connector and cable braid
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Dr. David Kirkby, Kirkby Microwave Ltd
gin&pez@arg
Sam Reaves
Oristo