LNB failure

[adm]

Just wondering if anyone has seen the failure I seem to have on my traditional quad lnb

I have one box with two satellite tuners and another box with one satellite tuner. The tuners are connected to 3 outputs from the quad lnb

On both boxes I have lost all the channels that are Horizontally polarised, Low. Also confirmed on all 3 tuners via the Vix signal finder facility and selecting a Hor/Lo transponder - no signal found.

Horizontal High is OK as are both Vertical Low and Vertical High which indicates that both boxes are producing both levels of control voltage and the 22kHz tone where required.

12.5V to 14.5V with no tone = vertical polarisation low band
12.5V to 14.5V with tone = vertical polarisation high band
15.5V to 18V with no tone = horizontal polarisation low band - all channels missing
15.5V to 18V with tone = horizontal polarisation high band

[twol]

Bad weather - rain/moisture in cables?

[BrokenUnusableAccount]

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[BrokenUnusableAccount]

Could there be a weird software (or hardware) bug on both boxes?
It's obviously very unlikely unless there is something unusual, so that nobody else has seen and reported this, but common to both your boxes.

I agree that a hardware fault in the LNB is by far the most likely explanation.

[adm]

Update: My replacement LNB hasn't turned up yet BUT on turning on my box today all my missing channels are back (on both boxes)

This may suggest that water has got to the guts of the LNB and 4 days of dry weather has died it out. I will get the ladder out when the new LNB turns up (weather permitting)

[adm]

Update 2

The picture explains it all


lnb.jpg


The plastic on the fitting collar was also brittle and a light leverage with a screwdriver snapped it from the metal dish arm.

LNB is approx 15 years old and gets the full sun (when no clouds) until about 11am.

New LNB and collar fitted plus alignment check in about 30 minutes. All those years ago I used some grease on the internal mating halves of the F connectors and although the grease was a bit stiff (cold morning) the F connectors were in perfect condition with no corrosion.

What I did find useful on top of the ladder was the Enigma Signal Meter App on my Android phone

https://play.google.com/store/apps/details?id=com.krkadoni.app.signalmeter&hl=en_GB&gl=US

Obviously my dish was already aligned but the app allowed me to change channels on my box from the top of the ladder and echoed the box's SNR and AGC values. A few tweaks to the LNB skew was near instantly seen with SNR changes.