[time-nuts] Teardown of Chinese made eBay GPS antenna.

[Mark Sims]

I can confirm that they work well on Glonass and Beidou.   I have not tried 
them on my Z12 with L2 signals.

Last night a big lightning strike across the street took out a tree.   Antenna 
survived without damage, but my antenna is on a 3 foot tripod on the ground...  
it was quite a brown-trousers producing, ear-ringing strike.  

BTW,  the HP/Symmeticom 58517A antenna splitter/amplifier seems to work well 
with Glonass/Beidou.  I don't think it does L2, etc.
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Gary E. Miller]

Yo Bob!

On Wed, 28 Mar 2018 16:37:07 -0400
Bob kb8tq  wrote:

> So, after only two months in transit my examples of the “Chinese GPS
> Antenna” are here to poke at.

Cool.  I just ordered one.  I'm finding some GPS need the 40dB LNA
this claims, as opposed to the usual 23dB or so.  Then I can stop
swapping L1/L2 and L1/GLONASS antennas.

RGDS
GARY
---
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
g...@rellim.com  Tel:+1 541 382 8588

Veritas liberabit vos. -- Quid est veritas?
"If you can’t measure it, you can’t improve it." - Lord Kelvin


pgpOHrl8RWkxw.pgp
Description: OpenPGP digital signature
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Bob kb8tq]

Hi

So, after only two months in transit my examples of the “Chinese GPS Antenna” 
are
here to poke at. They are from www.stotoncn.com  and 
are labeled as being their
part number GN-GGB0710. They clearly show 3.3V to 18V as the operating voltage
on the  box they came in and on the antennas. All labeling is in English. It 
appears 
they will happily sell you as many as you want on AliExpress for ~$67. All data 
indicates
they will run L1/L2 GPS, Glonass, and Beidu. That is what the labeling on the 
parts
indicates. There is some conflicting data on the web about L5 operation …. 
we’lll see 
how that part goes. All packaging, labeling, and QA stickers match what show up 
in 
pictures on the web site. As best I can tell from Mr Google , they are indeed  
legit 3.3V 
to 18V devices.

Bob

> On Feb 22, 2018, at 2:48 PM, John Green  wrote:
> 
> For those who have been following the saga of the Chinese made, eBay
> purchased antenna that failed, I may have an answer as to why it failed.
> I had to destructively disassemble it. I just could not get it apart any
> other way. I used a Chinese version of a Dremel tool with a metal saw
> blade. After making a huge mess with plastic particles everywhere, it
> revealed a circular FR4 board with two patch antennas mounted, one atop the
> other. I assume the smaller one to be the L1, and the larger to be L2. This
> part looks almost identical to the Trimble Microcentered antenna I worked
> on recently. On the back side of this is a metal shield  about 3 by 3
> inches soldered to the circular FR4 board. I switched to a abrasive wheel
> and took off some of the solder holding the shield to the board. Then,
> using a small screw driver, I went around the shield breaking the solder
> loose. The shield off revealed that the coax goes to some capacitors that
> couple RF out and through an inductor with some capacitors to ground and
> finally to a SOT23-5 package labelled LK33. This appears to be a Micrel
> MIC5203 3.3 volt regulator. It is shorted on the input side. I believe that
> putting anything over 7.5 volts on the input exceeded the power dissipation
> rating and caused it to fail. I plan on wiring up a more robust 3.3 volt
> regulator in its place and trying again. It looks like I will be able to re
> solder the shield back. The watertight integrity is gone for good. I think
> I can find a plastic box I can mount it in so I can at least experiment
> with it. I have sent a message to the seller detailing my findings. The
> Micrel part lists a 20 volt maximum input voltage, so in theory at least,
> this might have worked, and there might be some of these out there that
> don't fail.
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Graham / KE9H]

 > The Chinese have no concept of, or ignore, intellectual property rights.

Do not forget that China is a communist government and culture..
And has been since about 1948.
So no one left who was raised under a different system of government.
Under communism, every thing is owned by "the people."
If people can't individually own land or property, how could they possibly
own something like an idea?
It is a fundamentally incomprehensible concept.
So they don't think they are doing something wrong when use someone else's
idea, or software, or design.

But they have figured out that their foreign customers get all upset when
they do re-use their ideas and designs.

So the government is making "adjustments" so that they can fit in with the
rest of the world, but only recently.

Enough off-topic, sorry.

--- Graham

==

On Thu, Feb 22, 2018 at 9:42 PM, Ruslan Nabioullin 
wrote:

> On Thu, Feb 22, 2018 at 5:48 PM, djl  wrote:
> > Fine. The Chinese have no concept of, or ignore, intellectual property
> > rights.
>
> Which is not necessarily perverse---there exist people (most notably
> those of the so-called Pirate Party movements worldwide) who deem the
> legal theories of the copyright and the patent to be absurd.  That is
> all that I will say, for I do not wish to excessively deviate from the
> topic of discourse.
>
> -Ruslan
>
> --
> Ruslan Nabioullin
> Wittgenstein Laboratories
> rnabioul...@gmail.com
> (508) 523-8535
> 50 Louise Dr.
> Hollis, NH 03049
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Ruslan Nabioullin]

On Thu, Feb 22, 2018 at 5:48 PM, djl  wrote:
> Fine. The Chinese have no concept of, or ignore, intellectual property
> rights.

Which is not necessarily perverse---there exist people (most notably
those of the so-called Pirate Party movements worldwide) who deem the
legal theories of the copyright and the patent to be absurd.  That is
all that I will say, for I do not wish to excessively deviate from the
topic of discourse.

-Ruslan

-- 
Ruslan Nabioullin
Wittgenstein Laboratories
rnabioul...@gmail.com
(508) 523-8535
50 Louise Dr.
Hollis, NH 03049
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[William H. Fite]

With respect, Tom, discussion of quality issues is scarcely "social media."

But...it is your list so that's the last you'll hear from me on the topic.



On Thursday, February 22, 2018, Tom Van Baak  wrote:

> Let's keep this thread on topic and highly informative.
>
> Please treat time nuts as a technical mailing list, not social media.
>
> Thanks,
> /tvb
> Moderator, www.leapsecond.com/time-nuts.htm
>
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-- 
Patriotism is supporting your country all the time, and your government
when it deserves it.
--Mark Twain

We may be surprised at the people we find in heaven. God has a soft spot
for sinners. His standards are quite low.
--Desmond Tutu
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[time-nuts] Teardown of Chinese made eBay GPS antenna.

[William H. Fite]

Ignore intellectual property rights - yes
Abusive labor practices - yes (I'm a radlib, this bothers me enormously)
Counterfeit parts - sometimes

But...

Little or no quality control - not necessarily
Drive out better goods - only if buyers allow to happen

Because...

The reason that Chinese manufacturers make and sell cheap crap is because
resellers (I'm looking at you, Americans and Europeans) specify the lowest
possible prices so they can make the highest possible profits.

The Chinese economy is strongly supply-side oriented. Simply put, they
build to the market, with little government regulation. If you go to China
and negotiate for top quality designs, parts, manufacturing processes, and
quality controls, they will happily build you products that match similar
items that come from Rohde & Schwarz or other top-notch manufacturers. That
said, if you want cheap, they'll certainly give you cheap.

When we want someone to blame for garbage in the marketplace, a good place
to look is in the mirror. China is not in the charity business; they build
what people want to buy.



On Thursday, February 22, 2018, djl  wrote:

> Fine. The Chinese have no concept of, or ignore, intellectual property
> rights. They will cheerfully use 13 year old girls to put together stuff
> using counterfeit parts and ripped circuits. There is little or no quality
> control. The problem is that these goods drive better goods out of the
> market.
>
>
> On 2018-02-22 14:39, William H. Fite wrote:
>
>> I wish people would lighten up on Chinese goods. Perhaps you are not aware
>> that China builds for and sells to both the DOD and NASA. Chinese
>> manufacturers build to the specs they are given. You want cheap crap,
>> they'll build cheap crap. You want top quality, they'll build top quality.
>>
>>
>> On Thursday, February 22, 2018, Van Horn, David <
>> david.vanh...@backcountryaccess.com> wrote:
>>
>> According to the data sheet, it looks pretty well in spec, and the part
>>> has thermal shutdown.
>>> http://ww1.microchip.com/downloads/en/DeviceDoc/mic5203.pdf
>>>
>>> ESD hit maybe?
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>>>
> --
> Dr. Don Latham
> PO Box 404, Frenchtown, MT, 59834
> VOX: 406-626-4304
>
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-- 
Patriotism is supporting your country all the time, and your government
when it deserves it.
--Mark Twain

We may be surprised at the people we find in heaven. God has a soft spot
for sinners. His standards are quite low.
--Desmond Tutu
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Tom Van Baak]

Let's keep this thread on topic and highly informative.

Please treat time nuts as a technical mailing list, not social media.

Thanks,
/tvb
Moderator, www.leapsecond.com/time-nuts.htm

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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[djl]

Fine. The Chinese have no concept of, or ignore, intellectual property 
rights. They will cheerfully use 13 year old girls to put together stuff 
using counterfeit parts and ripped circuits. There is little or no 
quality control. The problem is that these goods drive better goods out 
of the market.



On 2018-02-22 14:39, William H. Fite wrote:
I wish people would lighten up on Chinese goods. Perhaps you are not 
aware

that China builds for and sells to both the DOD and NASA. Chinese
manufacturers build to the specs they are given. You want cheap crap,
they'll build cheap crap. You want top quality, they'll build top 
quality.



On Thursday, February 22, 2018, Van Horn, David <
david.vanh...@backcountryaccess.com> wrote:

According to the data sheet, it looks pretty well in spec, and the 
part

has thermal shutdown.
http://ww1.microchip.com/downloads/en/DeviceDoc/mic5203.pdf

ESD hit maybe?
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--
Dr. Don Latham
PO Box 404, Frenchtown, MT, 59834
VOX: 406-626-4304

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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Clint Jay]

Then Africa.

On 22 Feb 2018 22:42, "Bob kb8tq"  wrote:

> India
>
> > On Feb 22, 2018, at 5:37 PM, Van Horn, David  backcountryaccess.com> wrote:
> >
> >
> > "Some  of you are to young to remember when Javanese products were
> considered junk same storyBert Kehren"
> >
> > I've lived through Japan, Taiwan, and now China.  Who's next?  😊
> >
> >
> >
> >
> > ___
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Bob kb8tq]

India

> On Feb 22, 2018, at 5:37 PM, Van Horn, David 
>  wrote:
> 
> 
> "Some  of you are to young to remember when Javanese products were considered 
> junk same storyBert Kehren"
> 
> I've lived through Japan, Taiwan, and now China.  Who's next?  😊
> 
> 
> 
> 
> ___
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Van Horn, David]

"Some  of you are to young to remember when Javanese products were considered 
junk same storyBert Kehren"

I've lived through Japan, Taiwan, and now China.  Who's next?  😊




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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[ewkehren via time-nuts]

Some  of you are to young to remember when Javanese products were considered 
junk same storyBert Kehren


Sent from my Galaxy Tab® A
 Original message From: "Van Horn, David" 
 Date: 2/22/18  4:44 PM  (GMT-05:00) To: 
Discussion of precise time and frequency measurement  
Subject: Re: [time-nuts] Teardown of Chinese made eBay GPS antenna. 
I wasn't making any comment about Chinese goods, just the component in question.

-Original Message-
From: time-nuts 
[mailto:time-nuts-bounces+david.vanhorn=backcountryaccess@febo.com] On 
Behalf Of William H. Fite
Sent: Thursday, February 22, 2018 2:40 PM
To: Discussion of precise time and frequency measurement 
Subject: Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

I wish people would lighten up on Chinese goods. Perhaps you are not aware that 
China builds for and sells to both the DOD and NASA. Chinese manufacturers 
build to the specs they are given. You want cheap crap, they'll build cheap 
crap. You want top quality, they'll build top quality.


On Thursday, February 22, 2018, Van Horn, David < 
david.vanh...@backcountryaccess.com> wrote:

> According to the data sheet, it looks pretty well in spec, and the 
> part has thermal shutdown.
> http://ww1.microchip.com/downloads/en/DeviceDoc/mic5203.pdf
>
> ESD hit maybe?
> ___
> time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to 
> https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow 
> the instructions there.
>


--
Patriotism is supporting your country all the time, and your government when it 
deserves it.
--Mark Twain

We may be surprised at the people we find in heaven. God has a soft spot for 
sinners. His standards are quite low.
--Desmond Tutu
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Bob kb8tq]

Hi

As mentioned in another post, the part does claim to have thermal limit
built in. They appear to pulse test them at 150 ma and 16V so there is
indeed *something* that would suggest operation at 12V would be ok. 
I’d guess that the thermal regulation spec applies up to 16V and past that
you are on your own…..

I’d take a look at the bypass caps on the regulator. Looking back at the 
original test data, it may have simply gone unstable at the higher voltage.
A 0.1 uf on the input and 0.47 uf on the output seem to be the minimums. 

Bob

> On Feb 22, 2018, at 2:48 PM, John Green  wrote:
> 
> For those who have been following the saga of the Chinese made, eBay
> purchased antenna that failed, I may have an answer as to why it failed.
> I had to destructively disassemble it. I just could not get it apart any
> other way. I used a Chinese version of a Dremel tool with a metal saw
> blade. After making a huge mess with plastic particles everywhere, it
> revealed a circular FR4 board with two patch antennas mounted, one atop the
> other. I assume the smaller one to be the L1, and the larger to be L2. This
> part looks almost identical to the Trimble Microcentered antenna I worked
> on recently. On the back side of this is a metal shield  about 3 by 3
> inches soldered to the circular FR4 board. I switched to a abrasive wheel
> and took off some of the solder holding the shield to the board. Then,
> using a small screw driver, I went around the shield breaking the solder
> loose. The shield off revealed that the coax goes to some capacitors that
> couple RF out and through an inductor with some capacitors to ground and
> finally to a SOT23-5 package labelled LK33. This appears to be a Micrel
> MIC5203 3.3 volt regulator. It is shorted on the input side. I believe that
> putting anything over 7.5 volts on the input exceeded the power dissipation
> rating and caused it to fail. I plan on wiring up a more robust 3.3 volt
> regulator in its place and trying again. It looks like I will be able to re
> solder the shield back. The watertight integrity is gone for good. I think
> I can find a plastic box I can mount it in so I can at least experiment
> with it. I have sent a message to the seller detailing my findings. The
> Micrel part lists a 20 volt maximum input voltage, so in theory at least,
> this might have worked, and there might be some of these out there that
> don't fail.
> ___
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Van Horn, David]

I wasn't making any comment about Chinese goods, just the component in question.

-Original Message-
From: time-nuts 
[mailto:time-nuts-bounces+david.vanhorn=backcountryaccess@febo.com] On 
Behalf Of William H. Fite
Sent: Thursday, February 22, 2018 2:40 PM
To: Discussion of precise time and frequency measurement 
Subject: Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

I wish people would lighten up on Chinese goods. Perhaps you are not aware that 
China builds for and sells to both the DOD and NASA. Chinese manufacturers 
build to the specs they are given. You want cheap crap, they'll build cheap 
crap. You want top quality, they'll build top quality.


On Thursday, February 22, 2018, Van Horn, David < 
david.vanh...@backcountryaccess.com> wrote:

> According to the data sheet, it looks pretty well in spec, and the 
> part has thermal shutdown.
> http://ww1.microchip.com/downloads/en/DeviceDoc/mic5203.pdf
>
> ESD hit maybe?
> ___
> time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to 
> https://www.febo.com/cgi-bin/ mailman/listinfo/time-nuts and follow 
> the instructions there.
>


--
Patriotism is supporting your country all the time, and your government when it 
deserves it.
--Mark Twain

We may be surprised at the people we find in heaven. God has a soft spot for 
sinners. His standards are quite low.
--Desmond Tutu
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[William H. Fite]

I wish people would lighten up on Chinese goods. Perhaps you are not aware
that China builds for and sells to both the DOD and NASA. Chinese
manufacturers build to the specs they are given. You want cheap crap,
they'll build cheap crap. You want top quality, they'll build top quality.


On Thursday, February 22, 2018, Van Horn, David <
david.vanh...@backcountryaccess.com> wrote:

> According to the data sheet, it looks pretty well in spec, and the part
> has thermal shutdown.
> http://ww1.microchip.com/downloads/en/DeviceDoc/mic5203.pdf
>
> ESD hit maybe?
> ___
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/
> mailman/listinfo/time-nuts
> and follow the instructions there.
>


-- 
Patriotism is supporting your country all the time, and your government
when it deserves it.
--Mark Twain

We may be surprised at the people we find in heaven. God has a soft spot
for sinners. His standards are quite low.
--Desmond Tutu
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[Van Horn, David]

According to the data sheet, it looks pretty well in spec, and the part has 
thermal shutdown.
http://ww1.microchip.com/downloads/en/DeviceDoc/mic5203.pdf

ESD hit maybe?
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Re: [time-nuts] Teardown of Chinese made eBay GPS antenna.

[djl]

 Chinese made, ... This
part looks almost identical to the Trimble Microcentered antenna I 
worked

on recently.


Right. It's Chinese made. 'nuff said.

Don

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--
Dr. Don Latham
PO Box 404, Frenchtown, MT, 59834
VOX: 406-626-4304

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[time-nuts] Teardown of Chinese made eBay GPS antenna.

[John Green]

For those who have been following the saga of the Chinese made, eBay
purchased antenna that failed, I may have an answer as to why it failed.
I had to destructively disassemble it. I just could not get it apart any
other way. I used a Chinese version of a Dremel tool with a metal saw
blade. After making a huge mess with plastic particles everywhere, it
revealed a circular FR4 board with two patch antennas mounted, one atop the
other. I assume the smaller one to be the L1, and the larger to be L2. This
part looks almost identical to the Trimble Microcentered antenna I worked
on recently. On the back side of this is a metal shield  about 3 by 3
inches soldered to the circular FR4 board. I switched to a abrasive wheel
and took off some of the solder holding the shield to the board. Then,
using a small screw driver, I went around the shield breaking the solder
loose. The shield off revealed that the coax goes to some capacitors that
couple RF out and through an inductor with some capacitors to ground and
finally to a SOT23-5 package labelled LK33. This appears to be a Micrel
MIC5203 3.3 volt regulator. It is shorted on the input side. I believe that
putting anything over 7.5 volts on the input exceeded the power dissipation
rating and caused it to fail. I plan on wiring up a more robust 3.3 volt
regulator in its place and trying again. It looks like I will be able to re
solder the shield back. The watertight integrity is gone for good. I think
I can find a plastic box I can mount it in so I can at least experiment
with it. I have sent a message to the seller detailing my findings. The
Micrel part lists a 20 volt maximum input voltage, so in theory at least,
this might have worked, and there might be some of these out there that
don't fail.
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