Re: [time-nuts] Leakage, tinySA

[Hal Murray]

Dana Whitlow said:
> Hal, my 10 MHz birdie is at a level of about -95 dBm, which puts it a little
> more than 10 db above the noise floor in 3 kHz BW. 

My noise floor is fuzzy.  The bottom is -110, even when the display goes down 
to -120.  The fuzz is ~3 dB.

My 10 MHz birdie looks like it is below the -100 dB line, but the text for the 
marker often prints out something in the high 90s.  I think that's a narrow 
spike that is hard to see sneaking over the line.  So I'd call the height of 
my birdie to be a bit below 10 dB.


-- 
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Re: [time-nuts] Leakage, tinySA

[Dana Whitlow]

Hal, my 10 MHz birdie is at a level of about -95 dBm, which puts it a
little more than
10 db above the noise floor in 3 kHz BW.

I've found that the "spur removal" function sometimes works, but not
always, if I
change the IF frequency setting to 433.9 MHz.  It's mostly bimodal behavior-
sometimes the spur remover kills it entirely, but on some sweeps it only
reduces
the spur level by about 10 dB.  And on occasional sweeps the improvement is
by some other amount.

Dana


On Mon, Jan 18, 2021 at 2:47 PM Hal Murray  wrote:

>
> notfad...@gmail.com said:
> > FWIW I don't have spurs at 10MHz.
>
> Have you looked carefully?  I have to zoom in on the bandwidth in order to
> see
> it.  Somebody else called it a birdie.
>
> My unit came from R  I'm reasonably sure it's genuine.
>
> If I look at 10 MHz center and 25 or 100 k span, there is a faint
> something
> down in the noise.  Most of the time, the marker that automagically ends
> up on
> top of the highest peak is in the middle.  At a quick glance, there is
> nothing
> there.  If I look carefully, there is usually a small bump about 3 kHz
> wide.
>  It's easier to see at 25 kHz since it's wider.  It's faintly visible on a
> waterfall.
>
> That's with the antenna terminated or when I wander down the street.
> There is
> a similar thing at 50 MHz.
>
>
> --
> These are my opinions.  I hate spam.
>
>
>
>
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Re: [time-nuts] Leakage, tinySA

[Hal Murray]

notfad...@gmail.com said:
> FWIW I don't have spurs at 10MHz.

Have you looked carefully?  I have to zoom in on the bandwidth in order to see 
it.  Somebody else called it a birdie.

My unit came from R  I'm reasonably sure it's genuine.

If I look at 10 MHz center and 25 or 100 k span, there is a faint something 
down in the noise.  Most of the time, the marker that automagically ends up on 
top of the highest peak is in the middle.  At a quick glance, there is nothing 
there.  If I look carefully, there is usually a small bump about 3 kHz wide.   
 It's easier to see at 25 kHz since it's wider.  It's faintly visible on a 
waterfall.

That's with the antenna terminated or when I wander down the street.  There is 
a similar thing at 50 MHz.


-- 
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Re: [time-nuts] Leakage, tinySA

[Dana Whitlow]

BTW, I did purchase my 10MHz-"leaky" TinySA through R & L.  Had I not had
the clue that R & L was a reliable source, I would never have ordered one ot
these things at all.

Tom, I don't walk around- I pedal around on a recumbent trike.

Dana


On Mon, Jan 18, 2021 at 5:20 AM Bill Notfaded  wrote:

> Knock offs is part of the reason I posted the main US distributer earlier.
> The software is basically open source so anyone could theoretically make
> one.  There's only one original manufacturer though.  R Electronics is
> the only sanctioned US distributer I'm aware of.  Also they have the best
> price in US you can find for obvious reasons.  FWIW I don't have spurs at
> 10MHz.
>
> Bill in AZ
>
> On Sun, Jan 17, 2021, 5:35 PM Dana Whitlow  wrote:
>
> > Hi Dan,
> >
> > I remember seeing the list of checks to make regarding knockoff clones,
> > and even remember a few of them: to wit:
> >
> > 1. Comes in molded packaging, not poly foam.  Check!
> > 2. Has the internal shielding.  Check!
> > 3. Passes all the self tests, including 7 & 8.  Check!
> >
> > I had high hopes of moving the birdie off 10 MHz by changing the IF
> > frequency
> > setting, but this did no good.  I'd sure like to see a detailed block
> > diagram, but
> > do not know where to look.
> >
> > I also tried turning on the "spur eliminator", which did help by several
> > dB, but
> > my birdie still sits a few dB able the displayed noise floor in the
> > narrowest
> > available resolution BW of ~ 3 kHz.
> >
> > So, for the moment, I'm out of ideas.
> >
> > Thanks,
> >
> > Dana
> >
> >
> > On Sun, Jan 17, 2021 at 5:21 PM Dan Kemppainen 
> > wrote:
> >
> > > Dana,
> > >
> > > Just an FYI. Apparently, there are knockoff clone copies of the TinySA
> > > out there. (Yes, making a knockoff clone of a $50 spectrum analyzer is
> a
> > > thing, go figure!)
> > >
> > > Apparently, these have substandard performance, and a host of
> > > issues/concerns. I ran into this on the TinySA web site. They have some
> > > hints on how to detect if you have a clone or not. Might be worth
> > > looking into to see if you have a sub-par copy.
> > >
> > > Dan
> > >
> > >
> > >
> > >
> > > On 1/16/2021 12:00 PM, time-nuts-requ...@lists.febo.com wrote:
> > > > Date: Sat, 16 Jan 2021 05:45:19 -0600
> > > > From: Dana Whitlow
> > > > To: Discussion of precise time and frequency measurement
> > > >   
> > > > Subject: Re: [time-nuts] Leakage, tinySA
> > > > Message-ID:
> > > >> > qrjlg-bw68wgdahmlhe9qulpupijuqedapz...@mail.gmail.com>
> > > > Content-Type: text/plain; charset="UTF-8"
> > > >
> > > > Another data point:  My newly-received TinySA has a big birdie at 10
> > MHz,
> > > > which is a
> > > > disappointment since I had hoped to use the unit as a sniffer to
> track
> > > down
> > > > leaks in my
> > > > 10 MHz distribution system.  This birdie in the TinySA persists even
> > when
> > > > nothing is
> > > > connected to the input and does not vary in amplitude when I move
> > around
> > > > the house,
> > > > or with time while I'm sitting still with the unit.
> > > >
> > > > I, too, received no manual.
> > > >
> > > > Dana
> > >
> > > ___
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> > > To unsubscribe, go to
> > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> > > and follow the instructions there.
> > >
> > ___
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> > To unsubscribe, go to
> > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> > and follow the instructions there.
> >
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Re: [time-nuts] Leakage, tinySA

[Bill Notfaded]

Knock offs is part of the reason I posted the main US distributer earlier.
The software is basically open source so anyone could theoretically make
one.  There's only one original manufacturer though.  R Electronics is
the only sanctioned US distributer I'm aware of.  Also they have the best
price in US you can find for obvious reasons.  FWIW I don't have spurs at
10MHz.

Bill in AZ

On Sun, Jan 17, 2021, 5:35 PM Dana Whitlow  wrote:

> Hi Dan,
>
> I remember seeing the list of checks to make regarding knockoff clones,
> and even remember a few of them: to wit:
>
> 1. Comes in molded packaging, not poly foam.  Check!
> 2. Has the internal shielding.  Check!
> 3. Passes all the self tests, including 7 & 8.  Check!
>
> I had high hopes of moving the birdie off 10 MHz by changing the IF
> frequency
> setting, but this did no good.  I'd sure like to see a detailed block
> diagram, but
> do not know where to look.
>
> I also tried turning on the "spur eliminator", which did help by several
> dB, but
> my birdie still sits a few dB able the displayed noise floor in the
> narrowest
> available resolution BW of ~ 3 kHz.
>
> So, for the moment, I'm out of ideas.
>
> Thanks,
>
> Dana
>
>
> On Sun, Jan 17, 2021 at 5:21 PM Dan Kemppainen 
> wrote:
>
> > Dana,
> >
> > Just an FYI. Apparently, there are knockoff clone copies of the TinySA
> > out there. (Yes, making a knockoff clone of a $50 spectrum analyzer is a
> > thing, go figure!)
> >
> > Apparently, these have substandard performance, and a host of
> > issues/concerns. I ran into this on the TinySA web site. They have some
> > hints on how to detect if you have a clone or not. Might be worth
> > looking into to see if you have a sub-par copy.
> >
> > Dan
> >
> >
> >
> >
> > On 1/16/2021 12:00 PM, time-nuts-requ...@lists.febo.com wrote:
> > > Date: Sat, 16 Jan 2021 05:45:19 -0600
> > > From: Dana Whitlow
> > > To: Discussion of precise time and frequency measurement
> > >   
> > > Subject: Re: [time-nuts] Leakage, tinySA
> > > Message-ID:
> > >> qrjlg-bw68wgdahmlhe9qulpupijuqedapz...@mail.gmail.com>
> > > Content-Type: text/plain; charset="UTF-8"
> > >
> > > Another data point:  My newly-received TinySA has a big birdie at 10
> MHz,
> > > which is a
> > > disappointment since I had hoped to use the unit as a sniffer to track
> > down
> > > leaks in my
> > > 10 MHz distribution system.  This birdie in the TinySA persists even
> when
> > > nothing is
> > > connected to the input and does not vary in amplitude when I move
> around
> > > the house,
> > > or with time while I'm sitting still with the unit.
> > >
> > > I, too, received no manual.
> > >
> > > Dana
> >
> > ___
> > time-nuts mailing list -- time-nuts@lists.febo.com
> > To unsubscribe, go to
> > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> > and follow the instructions there.
> >
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Re: [time-nuts] Leakage, tinySA

[Dana Whitlow]

Hi Dan,

I remember seeing the list of checks to make regarding knockoff clones,
and even remember a few of them: to wit:

1. Comes in molded packaging, not poly foam.  Check!
2. Has the internal shielding.  Check!
3. Passes all the self tests, including 7 & 8.  Check!

I had high hopes of moving the birdie off 10 MHz by changing the IF
frequency
setting, but this did no good.  I'd sure like to see a detailed block
diagram, but
do not know where to look.

I also tried turning on the "spur eliminator", which did help by several
dB, but
my birdie still sits a few dB able the displayed noise floor in the
narrowest
available resolution BW of ~ 3 kHz.

So, for the moment, I'm out of ideas.

Thanks,

Dana


On Sun, Jan 17, 2021 at 5:21 PM Dan Kemppainen 
wrote:

> Dana,
>
> Just an FYI. Apparently, there are knockoff clone copies of the TinySA
> out there. (Yes, making a knockoff clone of a $50 spectrum analyzer is a
> thing, go figure!)
>
> Apparently, these have substandard performance, and a host of
> issues/concerns. I ran into this on the TinySA web site. They have some
> hints on how to detect if you have a clone or not. Might be worth
> looking into to see if you have a sub-par copy.
>
> Dan
>
>
>
>
> On 1/16/2021 12:00 PM, time-nuts-requ...@lists.febo.com wrote:
> > Date: Sat, 16 Jan 2021 05:45:19 -0600
> > From: Dana Whitlow
> > To: Discussion of precise time and frequency measurement
> >   
> > Subject: Re: [time-nuts] Leakage, tinySA
> > Message-ID:
> >qrjlg-bw68wgdahmlhe9qulpupijuqedapz...@mail.gmail.com>
> > Content-Type: text/plain; charset="UTF-8"
> >
> > Another data point:  My newly-received TinySA has a big birdie at 10 MHz,
> > which is a
> > disappointment since I had hoped to use the unit as a sniffer to track
> down
> > leaks in my
> > 10 MHz distribution system.  This birdie in the TinySA persists even when
> > nothing is
> > connected to the input and does not vary in amplitude when I move around
> > the house,
> > or with time while I'm sitting still with the unit.
> >
> > I, too, received no manual.
> >
> > Dana
>
> ___
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>
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Re: [time-nuts] Leakage, tinySA

[Dan Kemppainen]

Dana,

Just an FYI. Apparently, there are knockoff clone copies of the TinySA 
out there. (Yes, making a knockoff clone of a $50 spectrum analyzer is a 
thing, go figure!)


Apparently, these have substandard performance, and a host of 
issues/concerns. I ran into this on the TinySA web site. They have some 
hints on how to detect if you have a clone or not. Might be worth 
looking into to see if you have a sub-par copy.


Dan




On 1/16/2021 12:00 PM, time-nuts-requ...@lists.febo.com wrote:

Date: Sat, 16 Jan 2021 05:45:19 -0600
From: Dana Whitlow
To: Discussion of precise time and frequency measurement

Subject: Re: [time-nuts] Leakage, tinySA
Message-ID:

Content-Type: text/plain; charset="UTF-8"

Another data point:  My newly-received TinySA has a big birdie at 10 MHz,
which is a
disappointment since I had hoped to use the unit as a sniffer to track down
leaks in my
10 MHz distribution system.  This birdie in the TinySA persists even when
nothing is
connected to the input and does not vary in amplitude when I move around
the house,
or with time while I'm sitting still with the unit.

I, too, received no manual.

Dana


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Re: [time-nuts] Leakage, tinySA

[Mark Spencer]

I use RG400 for most of my time nuts activities.   When I switched from cheap 
RG58 style coax to RG400 a number of strange issues seemed to go away for me.   

Your mileage may vary (:



Mark Spencer
m...@alignedsolutions.com
604 762 4099

> On Jan 16, 2021, at 9:40 AM, Brian Lloyd  wrote:
> 
>> On 1/16/21 04:32, Hal Murray wrote:
>> 
>> The 10 MHz is stronger near coax carrying 10 MHz and next to a Z3801A.  I'll
>> have to try some good cables.  Anybody have a favorite source?  Is there a
>> magic word?  Do I have to specify the type of coax?
> 
> Yes. RG400 or RG316. Do NOT use RG58 or RG174. Both RG400 and RG316 are 
> double-shielded to reduce leakage. The choice is dictated by length of run 
> and physical flexibility required. Mostly I use RG316 cables on the bench. 
> For more than a meter or so I go with RG400. You can get either type of cable 
> terminated with N, BNC, TNC, or SMA connectors.
> 
> All kinds of pre-made cable assemblies using RG316 are available from Amazon 
> for surprisingly-low prices. I can't buy the coax and connectors for what I 
> end up paying Amazon for completed cables. For RG400 I end up making my own 
> cable assemblies.
> 
> The LMR cables (Times Microwave and knock-offs) are pretty good too. LMR195 
> is pretty good but not nearly as flexible as the aforementioned cables. 
> LMR400 is just too big and inflexible for easy use on the bench.
> 
> -- 
> 
> 
>  
> 
> Brian Lloyd
> 706 Flightline
> Spring Branch, TX 78070
> br...@lloyd.aero 
> +1.210.802.8359
> 
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Re: [time-nuts] Leakage, tinySA

[John Ackermann N8UR]

You can get custom-made decent quality cables with double shielded coax 
(either RG-316D or RG-142) from China (where else?) for pretty low 
prices.  I am sure the cable isn't mil-spec but I cut a piece open and 
the shield coverage, which is the main thing I worry about at HF 
frequencies, is pretty good.  The connector finish is sometimes a bit 
rough (particularly the BNC bayonet part) but they hold up pretty well 
and I haven't seen any damage from mating them.


The place I mainly work with is "RF Bat" or "SuperBat" at rfbat.com. 
Ask for Amy and tell her I sent you. :-) (no commercial relationship, etc.)


John


On 1/16/21 12:40 PM, Brian Lloyd wrote:

On 1/16/21 04:32, Hal Murray wrote:

The 10 MHz is stronger near coax carrying 10 MHz and next to a 
Z3801A.  I'll
have to try some good cables.  Anybody have a favorite source?  Is 
there a

magic word?  Do I have to specify the type of coax?


Yes. RG400 or RG316. Do NOT use RG58 or RG174. Both RG400 and RG316 are 
double-shielded to reduce leakage. The choice is dictated by length of 
run and physical flexibility required. Mostly I use RG316 cables on the 
bench. For more than a meter or so I go with RG400. You can get either 
type of cable terminated with N, BNC, TNC, or SMA connectors.


All kinds of pre-made cable assemblies using RG316 are available from 
Amazon for surprisingly-low prices. I can't buy the coax and connectors 
for what I end up paying Amazon for completed cables. For RG400 I end up 
making my own cable assemblies.


The LMR cables (Times Microwave and knock-offs) are pretty good too. 
LMR195 is pretty good but not nearly as flexible as the aforementioned 
cables. LMR400 is just too big and inflexible for easy use on the bench.




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Re: [time-nuts] Leakage, tinySA

[Brian Lloyd]

On 1/16/21 04:32, Hal Murray wrote:


The 10 MHz is stronger near coax carrying 10 MHz and next to a Z3801A.  I'll
have to try some good cables.  Anybody have a favorite source?  Is there a
magic word?  Do I have to specify the type of coax?


Yes. RG400 or RG316. Do NOT use RG58 or RG174. Both RG400 and RG316 are 
double-shielded to reduce leakage. The choice is dictated by length of 
run and physical flexibility required. Mostly I use RG316 cables on the 
bench. For more than a meter or so I go with RG400. You can get either 
type of cable terminated with N, BNC, TNC, or SMA connectors.


All kinds of pre-made cable assemblies using RG316 are available from 
Amazon for surprisingly-low prices. I can't buy the coax and connectors 
for what I end up paying Amazon for completed cables. For RG400 I end up 
making my own cable assemblies.


The LMR cables (Times Microwave and knock-offs) are pretty good too. 
LMR195 is pretty good but not nearly as flexible as the aforementioned 
cables. LMR400 is just too big and inflexible for easy use on the bench.


--


 

Brian Lloyd
706 Flightline
Spring Branch, TX 78070
br...@lloyd.aero 
+1.210.802.8359

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Re: [time-nuts] Leakage, tinySA

[Mike Feher]

Sorry for the poor grammar on my post below. 

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
848-245-9115

-Original Message-
From: time-nuts  On Behalf Of Mike Feher
Sent: Saturday, January 16, 2021 11:10 AM
To: 'Discussion of precise time and frequency measurement'

Subject: Re: [time-nuts] Leakage, tinySA

There is no birdies on mine that I can see, even as I decrease the RBW. -
Mike 

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
848-245-9115

-Original Message-
From: time-nuts  On Behalf Of Dana Whitlow
Sent: Saturday, January 16, 2021 6:45 AM
To: Discussion of precise time and frequency measurement

Subject: Re: [time-nuts] Leakage, tinySA

Another data point:  My newly-received TinySA has a big birdie at 10 MHz,
which is a disappointment since I had hoped to use the unit as a sniffer to
track down leaks in my
10 MHz distribution system.  This birdie in the TinySA persists even when
nothing is connected to the input and does not vary in amplitude when I move
around the house, or with time while I'm sitting still with the unit.

I, too, received no manual.

Dana




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Re: [time-nuts] Leakage, tinySA

[Mike Feher]

There is no birdies on mine that I can see, even as I decrease the RBW. -
Mike 

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell NJ 07731
848-245-9115

-Original Message-
From: time-nuts  On Behalf Of Dana Whitlow
Sent: Saturday, January 16, 2021 6:45 AM
To: Discussion of precise time and frequency measurement

Subject: Re: [time-nuts] Leakage, tinySA

Another data point:  My newly-received TinySA has a big birdie at 10 MHz,
which is a disappointment since I had hoped to use the unit as a sniffer to
track down leaks in my
10 MHz distribution system.  This birdie in the TinySA persists even when
nothing is connected to the input and does not vary in amplitude when I move
around the house, or with time while I'm sitting still with the unit.

I, too, received no manual.

Dana




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Re: [time-nuts] Leakage, tinySA

[Bob kb8tq]

Hi

> On Jan 16, 2021, at 5:32 AM, Hal Murray  wrote:
> 
> 
> My tinySA arrived a  few days ago.  I'm happy.
> 
> It comes in a nice box with an antenna that extends to a foot, a USB charging 
> cable (mini, not micro) and a couple of cables.
> 
> It doesn't come with a manual.  I haven't found a manual online.  Their web 
> site is pretty good, but sometimes I like a document organized to be read by 
> turning pages rather than following links.
> 
> The minimum receive bandwidth is 3.1 kHz.
> 
> The specs say the lower frequency limit is 100 kHz but the UI doesn't enforce 
> that.
> 
> My strongest signal is at 30 MHz.  It's -60 to -80 dBm as I wave it around.  
> At 100 kHz bandwidth, the noise floor is -110 dBm.  The 30 MHz blip is clean 
> enough to see the shape of the receive bandwidth filter.  (I'm assuming  the 
> raw signal is much narrower than 3 kHz.)
> 
> I haven't figured out where it is coming from.  At first, I thought it was 
> coming from low power do-it-yourself PCs.
>  https://www.mini-box.com/
> If I get near them, lots of spurs near 30 MHz come up out of the noise.  But 
> powering them off doesn't change the 30 MHz.
> 
> The 30 MHz is clean.  I'm guessing it's the 3rd harmonic of 10 MHz.  I only 
> have a few of them, but I don't like turning them off.  Or maybe the 2nd 
> harmonic from the Lucent boxes.  ??
> 
> The 10 MHz is stronger near coax carrying 10 MHz and next to a Z3801A.

First step is to pull the cable and put a 50 ohm load on the device ( 3801
in this case ). The radiation may not go down …. If it does go down, next
step is a clamp on ferrite on the coax. “Anything that will fit” is the first 
choice there ….

>  I'll 
> have to try some good cables.  Anybody have a favorite source?  Is there a 
> magic word?  Do I have to specify the type of coax?

If you don’t mind spending “many tens of dollars a foot” there are lots of 
choices 
out there. They often come with strange mating connectors so the cable
is only the start of the cash outlay.   

I would draw the line at LMR-400.

https://www.pasternack.com/50-ohm-low-loss-flexible-lmr400-pe-jacket-double-shielded-black-lmr-400-P.aspx
 


Note that the term “flexible” is more in comparison to “rigid metal jacket” 
than 
what you would normally expect on a test cable. 

If you do want to go a bit more fancy than LMR400, stick with eBay and ten 
cents on 
the dollar pricing… Connectors may be a bit worn, but the price is right. 

https://www.ebay.com/itm/Megaphase-SF4-S1S5-96T-DC-to-4-GHz-50-96-SMA-to-SMA-R-Angle-RF-Test-Cable/231773017446?hash=item35f6bf9566:g:GU0AAOSwv-NWYJ3S
 


This is simply what is out there and seems to work pretty well. It is not the 
best of the
best by any means. It *is* something you *can* find on eBay. 

If your application is one that rigid cable ( = solid metal jacket) will work, 
that 
probably is a better bet. A thicker metal jacket is often a better jacket at 10 
MHz. 

> 
> I have lots of Gigabit Ethernet.  I have a blob at 125 MHz, and spurs at 120 
> MHz and 130 MHz.  120 has a little brother 18 kHz higher.

Same trick with snap on ferrite cores applies here as well.  If the core is big
enough, putting one or more turns through the core may help. Core size
vs cable size is what will limit you there …

Fun !!!

Bob

> 
> The normal power up mode scans 0 to 350 MHz with enough attenuation so that 
> most of my signals are lost in the noise.  Sometimes it comes up without the 
> attenuation.  Then I can see all sorts of stuff.  The biggest ones are at 240 
> and 288 MHz.
> 
> I think there is a mode for overlaying displays.  I haven't investigated.
> 
> 
> Their web page has links to software to talk to it over the USB cable.  I 
> haven't investigated.  Plugging in the USB cable adds lots of cruft.  The 
> software would be unusable unless you are looking at a strong signal or at 
> something in a hole that the cruft misses.  It might work if you can freeze 
> the display, then plug in the USB cable to capture it.
> 
> 
> 
> -- 
> These are my opinions.  I hate spam.
> 
> 
> 
> 
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Re: [time-nuts] Leakage, tinySA

[Dana Whitlow]

Another data point:  My newly-received TinySA has a big birdie at 10 MHz,
which is a
disappointment since I had hoped to use the unit as a sniffer to track down
leaks in my
10 MHz distribution system.  This birdie in the TinySA persists even when
nothing is
connected to the input and does not vary in amplitude when I move around
the house,
or with time while I'm sitting still with the unit.

I, too, received no manual.

Dana


On Sat, Jan 16, 2021 at 5:28 AM Hal Murray  wrote:

>
> My tinySA arrived a  few days ago.  I'm happy.
>
> It comes in a nice box with an antenna that extends to a foot, a USB
> charging
> cable (mini, not micro) and a couple of cables.
>
> It doesn't come with a manual.  I haven't found a manual online.  Their
> web
> site is pretty good, but sometimes I like a document organized to be read
> by
> turning pages rather than following links.
>
> The minimum receive bandwidth is 3.1 kHz.
>
> The specs say the lower frequency limit is 100 kHz but the UI doesn't
> enforce
> that.
>
> My strongest signal is at 30 MHz.  It's -60 to -80 dBm as I wave it
> around.
> At 100 kHz bandwidth, the noise floor is -110 dBm.  The 30 MHz blip is
> clean
> enough to see the shape of the receive bandwidth filter.  (I'm assuming
> the
> raw signal is much narrower than 3 kHz.)
>
> I haven't figured out where it is coming from.  At first, I thought it was
> coming from low power do-it-yourself PCs.
>   https://www.mini-box.com/
> If I get near them, lots of spurs near 30 MHz come up out of the noise.
> But
> powering them off doesn't change the 30 MHz.
>
> The 30 MHz is clean.  I'm guessing it's the 3rd harmonic of 10 MHz.  I
> only
> have a few of them, but I don't like turning them off.  Or maybe the 2nd
> harmonic from the Lucent boxes.  ??
>
> The 10 MHz is stronger near coax carrying 10 MHz and next to a Z3801A.
> I'll
> have to try some good cables.  Anybody have a favorite source?  Is there a
> magic word?  Do I have to specify the type of coax?
>
> I have lots of Gigabit Ethernet.  I have a blob at 125 MHz, and spurs at
> 120
> MHz and 130 MHz.  120 has a little brother 18 kHz higher.
>
> The normal power up mode scans 0 to 350 MHz with enough attenuation so
> that
> most of my signals are lost in the noise.  Sometimes it comes up without
> the
> attenuation.  Then I can see all sorts of stuff.  The biggest ones are at
> 240
> and 288 MHz.
>
> I think there is a mode for overlaying displays.  I haven't investigated.
>
>
> Their web page has links to software to talk to it over the USB cable.  I
> haven't investigated.  Plugging in the USB cable adds lots of cruft.  The
> software would be unusable unless you are looking at a strong signal or at
> something in a hole that the cruft misses.  It might work if you can
> freeze
> the display, then plug in the USB cable to capture it.
>
>
>
> --
> These are my opinions.  I hate spam.
>
>
>
>
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> time-nuts mailing list -- time-nuts@lists.febo.com
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> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
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>
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[time-nuts] Leakage, tinySA

[Hal Murray]

My tinySA arrived a  few days ago.  I'm happy.

It comes in a nice box with an antenna that extends to a foot, a USB charging 
cable (mini, not micro) and a couple of cables.

It doesn't come with a manual.  I haven't found a manual online.  Their web 
site is pretty good, but sometimes I like a document organized to be read by 
turning pages rather than following links.

The minimum receive bandwidth is 3.1 kHz.

The specs say the lower frequency limit is 100 kHz but the UI doesn't enforce 
that.

My strongest signal is at 30 MHz.  It's -60 to -80 dBm as I wave it around.  
At 100 kHz bandwidth, the noise floor is -110 dBm.  The 30 MHz blip is clean 
enough to see the shape of the receive bandwidth filter.  (I'm assuming  the 
raw signal is much narrower than 3 kHz.)

I haven't figured out where it is coming from.  At first, I thought it was 
coming from low power do-it-yourself PCs.
  https://www.mini-box.com/
If I get near them, lots of spurs near 30 MHz come up out of the noise.  But 
powering them off doesn't change the 30 MHz.

The 30 MHz is clean.  I'm guessing it's the 3rd harmonic of 10 MHz.  I only 
have a few of them, but I don't like turning them off.  Or maybe the 2nd 
harmonic from the Lucent boxes.  ??

The 10 MHz is stronger near coax carrying 10 MHz and next to a Z3801A.  I'll 
have to try some good cables.  Anybody have a favorite source?  Is there a 
magic word?  Do I have to specify the type of coax?

I have lots of Gigabit Ethernet.  I have a blob at 125 MHz, and spurs at 120 
MHz and 130 MHz.  120 has a little brother 18 kHz higher.

The normal power up mode scans 0 to 350 MHz with enough attenuation so that 
most of my signals are lost in the noise.  Sometimes it comes up without the 
attenuation.  Then I can see all sorts of stuff.  The biggest ones are at 240 
and 288 MHz.

I think there is a mode for overlaying displays.  I haven't investigated.


Their web page has links to software to talk to it over the USB cable.  I 
haven't investigated.  Plugging in the USB cable adds lots of cruft.  The 
software would be unusable unless you are looking at a strong signal or at 
something in a hole that the cruft misses.  It might work if you can freeze 
the display, then plug in the USB cable to capture it.



-- 
These are my opinions.  I hate spam.




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