Using the "138MHz-4.4GHz USB SMA Source/Signal Generator/Simple Spectrum Analyzer" for TV/CATV/SAT

frankviana

frankviana

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Satellites/tv
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Brazil
jeallen01

jeallen01

Specialist Contributor
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Somewhere in England (possibly?)!
Este é o tipo de dc bloqueador?


Not those splitters!

VMA is referring to a DC blocker like this (I have one, and it works with SDRs when configured as he outlined) Axing SZU 14-00 DC blocker for Sat with F-connector: Amazon.co.uk: Electronics

PS: ignore the statement "This product cannot be configured to work in the UK. The Channel pre-selection and automatic channel programming features may not work." = totally irrelevant to use with a device like an SDR module.
 
Channel Hopper

Channel Hopper

Suffering fools, so you don't have to.
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29,969
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A little less analogue, and a lot more crap.
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UK
I use a two way splitter with DC block on one side. Despite the change in balancing components, the actual signals on both ports are so close at all frequencies the difference is not worth calculating. I wouldn't want to look up a compensation chart each time for corrections on a standalone DC blocker (with unknown characteristics) plus two more inline - F connections.
 
vma

vma

Regular Member
Messages
289
Location
Portugal
My Satellite Setup
RX: 3 motorized DiSEqC-1.2 dishes (100cm, 110cm, 120cm) + 7 regular dishes.
Main receiver: Vu+ Duo + many others & IRD
TX: Modulators for DVB-S/C/T + Dektec Modulators
Field Meter: Emitor, KWS, Kathrein, Unaohm, Promax, Spaun, Rover Instruments, ...
My Location
Portugal
Just to let you guys know I have been working on my software and introduced error map compensation/calibration. This enhances the precision and measurement possibilities. Please look at the latest posts in VMA's Satellite Blog .

It requires a device with TWO synthesizers (ADF4350/ADF4351), so the cheaper SMA device cannot be used.

The cheap SMA device is nice as a spectrum analyzer attached at the LOOP THROUGH output of a satellite receiver (you MUST use a DC blocker!) and my software adds some interesting features like automatic transponder recognition & export, as well as, instant satellite recognition.

Regards,
Vitor
 
M

moonbase

Small Dish Man
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2.0m Precision
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UK
How is a negative L.O. entered into a preset for a C-Band LNB, for example -5150 or -5950

Thank You


Sorted.
 
Last edited:
M

moonbase

Small Dish Man
Messages
2,561
My Satellite Setup
2.0m Precision
My Location
UK
Vitor,

I have a question about satellite recognition if you can please help?

I created a new 10.0 East transponder ini file from a full Ku-Band scan of 10.0 East using EBS Pro and saved it in the "transponder_lists" folder in the root VMA folder. When I run the VMA SSA tool with the relevant check boxes selected it does not recognise 10.0 East as one of the options for the satellite.

In the VMA SSA tool I was using a Ku LOW Band scan on H polarity via the loop out from a satellite receiver. The spectrum is showing frequencies from 10.0E but the satellite itself is not getting recognised. I would have thought that as the 10.0 East transponder ini file had been created fresh, just before the spectrum scan the satellite would have been recognised?

Or, have I updated the wrong file re satellite recognition?


I have pasted a picture of the spectrum below.

VMA_SSA_Satellite_Recognition.jpg
 
vma

vma

Regular Member
Messages
289
Location
Portugal
My Satellite Setup
RX: 3 motorized DiSEqC-1.2 dishes (100cm, 110cm, 120cm) + 7 regular dishes.
Main receiver: Vu+ Duo + many others & IRD
TX: Modulators for DVB-S/C/T + Dektec Modulators
Field Meter: Emitor, KWS, Kathrein, Unaohm, Promax, Spaun, Rover Instruments, ...
My Location
Portugal
Hi,

Sorry for the late response - I have been otherwise busy and somehow overlooked your question.

Can you please send me your *.ini file for 10.0E? I want to try it and check what is wrong.

Meanwhile, please rise the horizontal orange line that crosses the transponder by means of the Threshold setting. Also, increase the sensitivity by 1 or 2: this is the frequency search range and "1" means that the algorithm is allowed to consider transponders that are +/-1MHz off the ideal value.

Finally, verify that the decimal point used in the *.ini file is the same as in the other files: I think it must be a "." and not a ",". Also, check if the formatting is similar.

Regards,
Vitor
 
M

moonbase

Small Dish Man
Messages
2,561
My Satellite Setup
2.0m Precision
My Location
UK
Can you please send me your *.ini file for 10.0E? I want to try it and check what is wrong.

Vitor,

I have attached the 0100.ini file in text format and also the latest Ku-Low-H scan on 10.0E using the changes you advised.

.
 

Attachments

vma

vma

Regular Member
Messages
289
Location
Portugal
My Satellite Setup
RX: 3 motorized DiSEqC-1.2 dishes (100cm, 110cm, 120cm) + 7 regular dishes.
Main receiver: Vu+ Duo + many others & IRD
TX: Modulators for DVB-S/C/T + Dektec Modulators
Field Meter: Emitor, KWS, Kathrein, Unaohm, Promax, Spaun, Rover Instruments, ...
My Location
Portugal
@moonbase: Due to the fact that I am currently away from home quite frequently and because 10.0E is not a satellite I use often on the current setup, I have had no time to review this issue.

Please apologize and allow some more time!

Regards,
Vitor
 
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