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coda2a
21-07-20, 07:59
I have bought a new dish identical to the old Sky installed dish and re-positioned the new dish on the same house wall. Reason for this is a) old install position made it difficult for me to maintain a bedroom window and b) I wanted to have the option to install more satellite users. Given that the old dish and LNB had been installed a number of years ago I replaced all the "dish hardware" and upgraded the LNB from Quad to an Octo LNB. Both old and new LNB's by Sky - Octo LNB model J8LS.
Sky Box and subscription long gone so my ET8000 is purely Freesat via Astra 28.2E.

As expected struggled with dish alignment so purchased a TV and Sat signal finder.
The signal finder when connected between the ET8000 and the LNB (at the dish) by default on a non-aligned dish, should emit an audible tone a light 3 to 5 LED's - no tone and no LED's.
My assumption is that the receiver generates a voltage?

ET8000 tuner A and B configuration unchanged from old to new install.
Tuner A and B = AVL6211 (DVB-S2)
Config Mode - Simple, Mode - Single, Satellite - 28.2E Astra 2E/2F/2G,Send DiSEqc - No

My suspicion is that the Sat signal finder is faulty - any help and advice appreciated.

adm
21-07-20, 09:32
What model of tv and Sat signal finder?

You may just be so far off azimuth and elevation for the meter not to start registering.

Go to https://www.dishpointer.com/

Enter your postcode and select the satellite as 28.2E Astra 2E/ ASTRA 2F/ Astra 2G

On pressing search you should get an aerial photo of your district showing a green line to the satellite.

Zoom in on the image and click on the green blob at the end of line to pick it up and drag it to the exact position on your house where you have installed the dish.

Identify an object along this line that you can see from where you have installed the dish – the further this object is away from your house the better. Point the arm holding the LNB towards this object. This will start you off in the right ballpark direction

On a sky type dish and in many parts of the UK the arm holding the LNB is very close to being horizontal. A common mistake is that people think the arm should pointing upwards toward the satellite whereas in reality it just need to be moved upwards from the horizontal by a few degrees.
So start at the horizontal and gently and slowly move the arm upwards to see if your meter starts registering.

Once you start getting a response from your meter you have to determine the optimum position remembering that actually tightening the bolts can move the dish slightly.

Edit:
Are you using the existing cable or have you also replaced that and fitted new F plugs? If new check that you having accidentally got a bit of the braid touching the inner connector causing a short, and hence zero power supply voltage.

BrianTheTechieSnail
21-07-20, 16:28
I got the impression that my Zgemma H7 would cut the power to the dish of no signal appeared within a second or two.
Am I wrong?

adm
21-07-20, 16:44
I got the impression that my Zgemma H7 would cut the power to the dish of no signal appeared within a second or two.
Am I wrong?

I've just checked on my Zgemma H9s, tuned into BBC1 then removed cable from the wall socket. 19V on first measurement and 19V after 5 minutes. 19V may appear high but it wasn't feeding into 75 ohm load. My Zgemma H9s has only one satellite tuner.


Same check on my Xtrend 10000 with two satellite tuners.

Only voltage on the connector for tuner being used BUT no voltage from any tuner connector very shortly afterwards so for the original poster his assumption that the box provides the power for his meter may/is wrong.

The original poster could probably power his meter by making up a short lead and connecting a PP3 9V battery. My sat finder meter has a internal 9V battery to provide power to the LNB and to power its own electronics.

BrianTheTechieSnail
21-07-20, 16:47
I guess I'm wrong then.
Please ignore my post.

Sent from my SM-N9005 using Tapatalk

adm
21-07-20, 17:07
I guess I'm wrong then.
Please ignore my post.


No :)
see my edit about my Xtrend box.

slacker17
22-07-20, 21:26
Have you tried using an apps signal meter such as within dreamDroid or tiMote?

Joe_90
23-07-20, 00:46
It would seem odd to me if the box (any box) powered off the LNB voltage in the event of no signal. Now, it might power off in the event of a shorted cable (protection for the electronics), or possibly if no load was present (no current draw from the LNB). My Mutant HD51 will power off the LNB when I switch to the terrestrial tuner and I have nothing tuned/recording on the sat tuner, but if I have . The cable itself wouldn't present any significant DC resistance - the 75ohm refers to its RF impedance. I'm assuming the OP had the meter connected correctly to the LNB and to the box. Usually you can test that it is powered by turning the sensitivity knob on the meter and the needle will show a full deflection, then you turn it back until the meter needle (or LEDs) show no signal. Then you adjust the dish azimuth and elevation to get the best signal and lastly rotate the LNB in its holder for maximum SNR, though SKY dishes usually have the skew pre-set.

adm
23-07-20, 08:37
It would seem odd to me if the box (any box) powered off the LNB voltage in the event of no signal. Now, it might power off in the event of a shorted cable (protection for the electronics), or possibly if no load was present (no current draw from the LNB). .

In retrospect I did test my Xtrend 10K without a terminating load on the cable. I just carefully unscrewed the cable from the wall plate to check the voltages - definitely no short circuits and the exercise was repeated a couple of times with the box just used for one live TV channel then live TV plus multiple recordings. The box may have sensed no 75 ohm termination.

Unfortunately it’s not to easy to repeat the test
i) no breakout cable
ii) I’ve since taken the opportunity to clean up the spaghetti behind the TV and the cables to the wall plate are now very short and difficult to access.

Some cheap TV sat meters don’t have a sensitivity control just LEDs to indicate strength. My more expensive TV Sat meter is the same but the LED bar consists of around 15 discrete LEDs rather than the limited number on the OPs meter.

coda2a
27-07-20, 14:05
Update - Many Thanks to all who have contributed to assist.
I paid for a satellite installer to attend - he had a professional meter and aligned the dish for me within 10-15 minutes.

Admin - My satellite cabling was unchanged to and from the XTrend receiver to the new dish position, albeit cables shortened with F connectors installed correctly no shorts with braiding etc.
Signal finder meter purchased by me was faulty and was confirmed as faulty by a) the manufacturer Fringe Electronics and b) connecting the meter to the dish once aligned - I think this is called Sod's Law.

Once again thanks for your help!