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Hi,
which firmware have you used? I found out that the newest cloned firmwares for the SAA2 has a worse quality than older. The firmwares until Sept. 2020 are OK. Later versions are not usable. I posted it but no of the developers are interested in it. Unfortunately only one user has answered.

--
Klaus, DL5KV

load measured 50.1 on my VOM as soon as I say DONE it starts is there a repair facility anywhere? Silly thing, I really liked using it for antenna analysis. sigh..

Yes. 5W is +37 dBm. This attenuator can handle 5W continuously, and its 41 dB attenuation will reduce the transmitter signal to -4 dBm. The TinySA max input power is +10 dBm with its internal attenuator set to 0 dB, so you are ok. Using more attenuation in the TinySA might be prudent. Note the qrpkit attenuator upper frequency limit is 200 MHz. Its attenuation will probably be reduced at higher frequencies.
Dave

Cierra <dubosec@...> wrote:

So, in theory an attenuator like this connected between a 5W
transmitter and TinySA would work?

Sent with mySecureMail.

So, in theory an attenuator like this connected between a 5W transmitter and TinySA would work?

Need check calibration kit/RF connectors/cable

If before calibration all look good, i think problem in 50 Om calibration, check it

This is what it does immediately after I save the cal data to 0 slot. Wow

ok it accepted
config and all data cleared... yea So far so good..
73 Paul

HI Roger
got it into terminal mode and ran Clearconfig but its not happy w the "1234" Then what ???

Drake TR7/TR4310.

73

-Jim
NU0C

On Mon, 15 Feb 2021 03:31:07 +0100
"Dragan Milivojevic" <d.milivojevic@...> wrote:

Forgot to ask, what's this legendary piece of equipment,
it has transistors so it can't be that good ?

On Mon, 15 Feb 2021 at 03:27, Jim Shorney <jshorney@...> wrote:

Yeah, I remembered that about the one on the left after I sent the pic.
The one on the right he called a "buzz kill".

73

-Jim
NU0C

On Mon, 15 Feb 2021 02:07:44 +0000 (UTC)
"Bob Albert via groups.io" <bob91343@...> wrote:

The left hand one is bypassed with a .01 so that doesn't count. I am

puzzled by the other one; what's it supposed to do?

The file you want is NanoVNA-App.rar. It is a rar archive, which is similar to a ZIP.

73

-Jim
NU0C


On Sun, 14 Feb 2021 16:49:46 -0800
"paul kobetz" <pkobetz@...> wrote:

Roger TU for the reply I wish i understood what you are referring to? I went to the OneofEleven site and it is in GitHub I dont see an executable file which I could run.

Forgot to ask, what's this legendary piece of equipment,
it has transistors so it can't be that good ?

Not the one on the right. See my previous post.

73

-Jim
NU0C

On Mon, 15 Feb 2021 03:14:37 +0100
"Dragan Milivojevic" <d.milivojevic@...> wrote:

In parallel with a 10nF cap ...

On Mon, 15 Feb 2021 at 03:02, Jim Shorney <jshorney@...> wrote:

And yet here we have two electrolytics in an RF circuit in a legendary
piece of ham gear. I asked an actual rocket scientist about it and he
didn't think it was anything unusual.

73

-Jim
NU0C

On Mon, 15 Feb 2021 00:55:06 +0100
"Dragan Milivojevic" <d.milivojevic@...> wrote:

That makes no sense whatsoever.

On Sun, 14 Feb 2021 at 23:14, Manfred Mornhinweg <manfred@...>

wrote:

And what's the best bypass cap? Well, a single, plain, cheap aluminium
electrolytic!

Attached is the impedance plot for a 47?F, 25V electrolytic cap,

measured

with lead lengths compatible with mounting it snugly on a PCB. Their

narrow

pin spacing helps a lot in keeping their ESL low. I kept the same

scale to

make comparison easy.

YES, a single 47?F electrolytic is a much better bypass cap than a
parallel combination of two ceramic caps of different values! Even in

the

low VHF range!

The problems with electrolytic caps is that their ESR rises with age,

and

rises much faster if they run hot, or if they have to carry large

ripple

current. So they can't be applied in every situation. But in situations
that are kind to them, they are the cheapest and easiest way to get an
excellent wideband bypass.

Yeah, I remembered that about the one on the left after I sent the pic. The one on the right he called a "buzz kill".

73

-Jim
NU0C

On Mon, 15 Feb 2021 02:07:44 +0000 (UTC)
"Bob Albert via groups.io" <bob91343@...> wrote:

The left hand one is bypassed with a .01 so that doesn't count.? I am puzzled by the other one; what's it supposed to do?

In parallel with a 10nF cap ...

Can you connect to the NanoVNA-H with the NanoVNA Sharp program? Do a calibration and remember to press Reset before you start and Done when you are finished. Save to a slot like 4. Then see if you can get the short, open and load on the left, middle and right of the Smith chart in the Sharp program. This will at least let you know if the NanoVNA can work in PC mode. If that works see if you can measure something in the sharp program.

The NanoVNA can be sent commands over the USB connection if you have a terminal program like Teraterm or Putty installed on your computer. This is called console mode. You just install TeraTerm which is free and then connect to the NanoVNA over the COM port. You can then send it commands like Clearconfig 1234. Search the Wiki for this group, previous messages and the files section of this group for further discussion of console mode.

Roger

The left hand one is bypassed with a .01 so that doesn't count.? I am puzzled by the other one; what's it supposed to do?

And yet here we have two electrolytics in an RF circuit in a legendary piece of ham gear. I asked an actual rocket scientist about it and he didn't think it was anything unusual.

73

-Jim
NU0C

On Mon, 15 Feb 2021 00:55:06 +0100
"Dragan Milivojevic" <d.milivojevic@...> wrote:

That makes no sense whatsoever.

On Sun, 14 Feb 2021 at 23:14, Manfred Mornhinweg <manfred@...> wrote:

And what's the best bypass cap? Well, a single, plain, cheap aluminium
electrolytic!

Attached is the impedance plot for a 47?F, 25V electrolytic cap, measured
with lead lengths compatible with mounting it snugly on a PCB. Their narrow
pin spacing helps a lot in keeping their ESL low. I kept the same scale to
make comparison easy.

YES, a single 47?F electrolytic is a much better bypass cap than a
parallel combination of two ceramic caps of different values! Even in the
low VHF range!

The problems with electrolytic caps is that their ESR rises with age, and
rises much faster if they run hot, or if they have to carry large ripple
current. So they can't be applied in every situation. But in situations
that are kind to them, they are the cheapest and easiest way to get an
excellent wideband bypass.

Paul,
Make sure you didn't turn OFF the calibration on the unit. In the calibration menu there is an Apply checkbox...make sure it's checked. However, with that said, sometimes it flips a bit and if you uncheck the box, calibration turns back on.?
Have a look.?


On Sun., 14 Feb. 2021 at 7:05 p.m., paul kobetz<pkobetz@...> wrote: My beautiful unit suddenly started to just start drawing lines all over the screen? I hv recalibrated it several times.. Something is wrong as it was working fine. Question is there a reset ?? Is there a repair facility or is it just disposable ??
Thank You Paul Kobetz K2HZO? Rubicon Observatory, Ukiah, Ca

Found a better YouTube video that describes the limits as a spectrum analyzer:


73
Evan
AC9TU

On Sun, Feb 14, 2021 at 03:59 PM, Bob Albert wrote:

I have measured electrolytic capacitors with my nano and they are woefully
bad at high frequencies.? Now that I have acquired a nanoVNA that can go down
to 10 kHz I plan to do some testing to see if they are just as bad at that
frequency.
Bob

Bob,

I thought you might find this interesting. I took a small Siemens 10 uF 40V electrolytic and made some measurements on a DE-5000 RLC meter and compared them with the NanoVNA. At 10 kHz. and 100 kHz. The results were very close. Most manufacturers rate their electrolytics at 100 or 120 Hz. so these measurements are in the table below.

You can see on the plots that this one went into self resonance at 420 kHz which is low and probably due to the fact that I left the leads at 1 inch long.

Roger