Author Topic: bg7tbl gpsdo master reference  (Read 186868 times)

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Offline n3mmr

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Re: bg7tbl gpsdo master reference
« Reply #775 on: September 18, 2019, 09:25:05 am »
I sent BG7TBL an email regarding the accuracy of the 2019-03-25 unit referencing my eevblog post. Here is his response:

"hello this normal.there is deviation with this type gpsdo.you can see other friend test result.this version is peak to peak is small value. lcd-gpsdo not this problem. thanks bg7tbl"

When queried as to which models do not have the problem the response was:

"this version" with the image included below:

[Note image appears not to be posting. The image is of a unit with a 2017-12-16 date code with the one line display on the side opposing the connectors.]

I find BG7TBL's reply difficult to understand, me not being a native english speaker and not familiar with chinese either.

Can someone clarify?

Also, a single unit of a specific date code is not statistically significant.
Have you tested any other identical units?
 

Offline kj7e

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Re: bg7tbl gpsdo master reference
« Reply #776 on: September 22, 2019, 01:24:09 am »
I sent BG7TBL an email regarding the accuracy of the 2019-03-25 unit referencing my eevblog post. Here is his response:

"hello this normal.there is deviation with this type gpsdo.you can see other friend test result.this version is peak to peak is small value. lcd-gpsdo not this problem. thanks bg7tbl"

When queried as to which models do not have the problem the response was:

"this version" with the image included below:

[Note image appears not to be posting. The image is of a unit with a 2017-12-16 date code with the one line display on the side opposing the connectors.]

I find BG7TBL's reply difficult to understand, me not being a native english speaker and not familiar with chinese either.

Can someone clarify?

Also, a single unit of a specific date code is not statistically significant.
Have you tested any other identical units?

I believe he means the frequency offset is typical on the version in your thread.  The 2017-12 LCD versions do not seem to have this offset.
 

Offline kj7e

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Re: bg7tbl gpsdo master reference
« Reply #777 on: September 22, 2019, 01:34:58 am »
Comparing the Trimble vs my NEO-M8T modified BG7TBL GPSDO.  HP 53132A, 100 sec count, 100 count statistical mean average.  They tend to agree quite well, within 5uHz from 10MHz or <5x10^14
« Last Edit: September 22, 2019, 02:05:55 am by kj7e »
 
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Offline haydenph

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Re: bg7tbl gpsdo master reference
« Reply #778 on: October 09, 2019, 10:05:13 pm »
I've had my BG7TBL GPSDO for a while, bought the distribution amp the other day and very happy with it.
Does anyone know if the issue with the frequency not being exactly on 10 MHz has been resolved in the later revisions?


 


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