sat receiver with signal strength output

[dreambox1959]

does anyone have a sat receiver that has an AGC or signal strength output?
I'm not talking about our old Echostar models from the analog era.

 

[suedschwede]

There will no longer be a receiver with a signal output, perhaps the Gold Master 525 combo could be evaluated using software.
Enigma2 would also work, there are also tools (dvb-fe-tool, dvb-femon, dvbsnoop) to output the received values.

 

[Channel Hopper]

All DVB tuner chips have a pin which can be tapped for an output.

 

[dreambox1959]

I will try but it is very difficult to weld at this place !!!!

 

[Channel Hopper]

I will try but it is very difficult to weld at this place !!!!

View attachment 151001

The track looks large enough to scrape away the coating.

 

[dreambox1959]

I soldered a wire to the point between the AGC loop resistors.
I get a voltage between 0V and 2V max.
But rather between 1.2v and 1.9V.
The value reflects the power value received but not the SNR but it is still very related.

%	v
34	1,2
58	1,53
61	1,56
63	1,58
66	1,63
74	1,73
85	1,9

I will try to use this value to do an autofocus......

 

[dreambox1959]

I tested a small interface to amplify the AGC signal and adapt the impedance.
I will try a display with a galvanometer (like before!!) then with an AD converter I would manage that with the positioner.
this schematic comes from an RC2K positionner.

 

[dreambox1959]

I received my circuit boards. I built the map, adjusted the values and tested!!! very useful on KU band (less effective on C band?).
I set the starting offset P3 to detect at a useful level then the gain P2 to have a maximum amplitude.
in the following examples there is astra19.2 with an offset of 73% then an adjustment and 99%. the dial displays the AGC level but it is instantaneous, not like through the screen display, moreover you can adjust the position by viewing the channel.
it is very reactive, it becomes easier to find the maximum position.

 

[Channel Hopper]

I received my circuit boards. I built the map, adjusted the values and tested!!! very useful on KU band (less effective on C band?).
I set the starting offset P3 to detect at a useful level then the gain P2 to have a maximum amplitude.
in the following examples there is astra19.2 with an offset of 73% then an adjustment and 99%. the dial displays the AGC level but it is instantaneous, not like through the screen display, moreover you can adjust the position by viewing the channel.
it is very reactive, it becomes easier to find the maximum position.
View attachment 151326

View attachment 151327

Well there you are.

 

[dreambox1959]

to connect an agc meter , you have to solder a wire in a hard-to-reach place
it s better to remove the card reader .


find resistor R285


use a very small wire and a small solder iron.



add two RCA jack




for diseqc output put an 100R resistor and on AGC output an 10K resistor

 

[dreambox1959]

here is the sf8008 from UDO (Aal41) I added the signal strength buffer card!

 

[dreambox1959]

I'd like to give you an update on the positioner autofocus project:
The printed circuit boards are ready, and the wiring is almost complete.

The operation (for now) is as follows: I measure the AGC level at the starting point, then take 5 measurements moving eastwards, then another 5 westwards, and I detect the highest value to return to this position at the end of the cycle (this is the same process as in the receiver-positioners of yesteryear like the echostar).

 

[moonbase]

I'd like to give you an update on the positioner autofocus project:
The printed circuit boards are ready, and the wiring is almost complete.

The operation (for now) is as follows: I measure the AGC level at the starting point, then take 5 measurements moving eastwards, then another 5 westwards, and I detect the highest value to return to this position at the end of the cycle (this is the same process as in the receiver-positioners of yesteryear like the echostar).

The old Echostar receivers used to ony work on Analogue as far as I am aware?
This is really nice work to get it operational for digital.

 

[moonbase]

I'd like to give you an update on the positioner autofocus project:
The printed circuit boards are ready, and the wiring is almost complete.

The operation (for now) is as follows: I measure the AGC level at the starting point, then take 5 measurements moving eastwards, then another 5 westwards, and I detect the highest value to return to this position at the end of the cycle (this is the same process as in the receiver-positioners of yesteryear like the echostar).

Do you have plans to sell an SF8008 and a positioner as a complete kit?
Or, if members were to send you an SF8008 could it be modified to work with one of your positioners?

 

[dreambox1959]

Do you have plans to sell an SF8008 and a positioner as a complete kit?
Or, if members were to send you an SF8008 could it be modified to work with one of your positioners?

1st question : no
2nd question : yes !!

i pick AGC signal from rda5815m (1v = no signal 2v full agc = 99% on screen)
i read with an a/d converter fom 1.5v to 2V

certainly it needs to be fixed in future !!!

 

[dreambox1959]

i build 3 sf8008 with AGC add-on card .

 

[dreambox1959]

The AGC signal is taken from the connection between pin 5 of the RDA5815M and SI2166D pin 1.
The signal is a PWM filtered by a 4.7K resistor and a capacitor. The amplitude after the resistor is between 0V and 2V.
The useful part is between 1.4v (50%) and 2v (100%), the interface stage adapts the impedance then amplifies the voltage variation between 1.4v and 2V (threshold at 1.45v gain between 5 and 10).
At the output the signal varies between 0V and 3.5V, this signal, through a resistor, activates the galvanometer.
The same signal is sent to the positioner or an A/D converter (TLC548) gives the information to the microprocessor and makes it possible to adjust the position where the signal is maximum.
The program takes several steps forward and backward comparing the AGC power to find the best result and returns the dish to that point.

youtube:

the starting value is 2212, the program tests the AGC from 2212 to 2220 then 2212 to 2204, the best result is found at 2214

 

[dreambox1959]

I designed this system to have an auto-focus function with my positioner and my sf8008. but the system is surely adaptable to other receivers than the sf8008.
but also we can appreciate having only a galvanometer which displays the power received without having my positioner.
If you are interested contact me

 

[pipino]

TOP JOB !! ..Well done

 

[dreambox1959]

Does anyone have a source to find a magnetic wheel like that of the actuator reed sensor? I have a 6 pole wheel, I am looking for an 8 or 10 pole version.

8 Poles Magnetized Synchronous Motor Magnet China Manufacturer

China 8 Poles Magnetized Synchronous Motor Magnet with High-Quality, Leading 8 Poles Magnetized Synchronous Motor Magnet Manufacturers & Suppliers, find 8 Poles Magnetized Synchronous Motor Magnet Factory & Exporters.

www.ybmagnet.com