Variable Signal Quality and No Lock

[Hungry Hedgehog]

I have an Amstrad digibox and started getting poor quality (blockiness) pictures. Eventually, the picture stopped completely and I bought a 60cm oval dish and Thomson quad LNB from ebay.

I've installed it and aligned it using the old dish as an approximate directional reference.

I found two signals. The first locked on but was not Sky (too far east). Now I can see a very strong signal but the quality indicator is swinging from nothing to very good every few seconds and it won't lock so I can't positively identify it but I think it's the right one.

I've visually checked the cable and it looks good as do the terminations.

Has anyone any experience of this? Not sure if I need to go back to eBay for a new box.

Thanks!

 

[fernandez]

You may find this useful

http://www.sam-radford.me.uk/install.htm

Take note of the section dealing with the 'skew' of the dish and LNB as this, by the sounds of things, may be where the problem is

 

[SamRadford]

Sounds to me like the Amstrad receiver has a faulty capacitor problem. Not necessarily the power supply.

 

[Hungry Hedgehog]

Sounds to me like the Amstrad receiver has a faulty capacitor problem. Not necessarily the power supply.

Thanks for the suggestion. I've just been in to see my neighbours and connect my box to their system and it works fine. Therefore, it seems that there are only three possibilities:

1. The cable is damaged and needs replacing
2. The dish is not correctly aligned
3. I've been really unlucky and got a duff LNB

3 seems unlikely. I've spent ages playing with the alignment of the dish and can't seem to get any better strength so doubt it's 2. Therefore, I'm going to assume the cable has been damaged (where it's tight through the window frame) and replace it.

Or can anyone suggest a fourth?

Thanks to those that have offered assistance.

Cheers!

 

[SamRadford]

What you describe is typical of an intermittent Amstrad DRX100 tuner module fault. Sometimes it works and sometimes it doesn't. If it's not a DRX100 then kindly tell us what it is.

 

[Cupart]

I would also check that none of the outer-threaded cable is touching the main copper thread in the middle (unscrew the f-connector) as this could have something to do with it.

Also, if the f-connectors have been subjected to rain (or other moisture) it could have "corroded" meaning that it has turned green and won't conduct the signal very well...

Check all connectors and "re-fresh" if needed (meaning cut the old tip off and re-do)!

 

[Hungry Hedgehog]

I would also check that none of the outer-threaded cable is touching the main copper thread in the middle (unscrew the f-connector) as this could have something to do with it.

Also, if the f-connectors have been subjected to rain (or other moisture) it could have "corroded" meaning that it has turned green and won't conduct the signal very well...

Check all connectors and "re-fresh" if needed (meaning cut the old tip off and re-do)!

I had visually checked the cable and connections and they appeared perfect. Nonetheless, as the cable run is short, I replaced the cable. Within one minute of starting to adjust the dish I had a perfect signal and it's been fine now for a week. My guess is that the cable may have been damaged where it entered the house as it was tight under the window frame.



Thanks to everyone who offered advice!