Just noticed I have lost all the horizontal channels on both satellite rxs......is it as simple as a duff lnb or coupled with the fact I am getting a shock off the outer of all the f connectors could it be a cable/plug fault .....I get the shock with either rx switched on or both on so probably not the rx.????...not got any test equipment here at the static van so probably start with bringing down a new four way lnb the next time I come down ? ....if that doesn't cure it check all the cables for shorts? ....anybody had this fault?...
bloody satellites
Jun 09, 2019
Last reply: 7 years ago
77 Replies
I wouln't think the events are related. A working recceiver has a very "feelable" ac Voltage on the LNB output.
There is not usually a ground on the receiver and the capacitive leakage from mains to equipment provides the "tingle". I do ground the receiver now when setting up a system on damp ground.
With no direct means of measurement a spud will detect Voltage and polarity.
Plus gives a blue ring.
I did have a discussion with a marine Engineer who said that the spud had to be a King Edward. I don't actually think this is the case, but since the introduction of DMM's I never really had reason to check.
AB
When I was installing systems for friends and family there was a separate polariser but I'm guessing these things are all built into the LNB these days?
Assuming they work as they did with the polarity being twisted +- 45 degrees (if I remember it correctly) I can't see how the polariser could not work both ways if it can work one (it only being a coil etc)?
I think I used to get that sometimes.
Only if they weren't done properly in the first place and / or have been move about since they were?
Is that with all feeds disconnected from the LNB (if it has more than one etc)?
Can't hurt if you have one or they are cheap enough. I'm guessing such things would be vulnerable to electrical impulse nose etc?
I'm sure there must be. ;-)
Cheers, T i m
I have never had a tingle off the outer of an lnb plug before only this set up.......I will get a new lnb because they a dirt cheap these days and I bet the tingle will go but if it doesn't I will test the four cables for shorts and re-plug them...just wondered with no horizontal signals and full scale vertical it would be an lnb fault causing the "tingle"...... .thanks
you're having a laugh shirley ? .....
No, not at all.
There was a time when wireless amateurs had to know some electrical and electronic theory.
That was before the major skill requirement decended to figuring out how to open the box the latest LED festooned pile of garbage came in.
AB
if you think the lnb is switched by ac voltage I think you are the one with a problem not me.....go away
Oh My God!!
A G4?
What the hell have things decended to?
This isn't even electrical in nature, it's common sense.
Power comes into receiver, travels via cable to LNB
Tingle from cable/ LNB, it must be the LNB then ???
Good job you don't have problems with te water supply.
No water for kettle, change bathtub :-)
Could it be the satellite? A Dalek invasion swamping the Sky transponder with comm's.
Voltage transmitted to Earth so fantastically huge it electrocutes confused G4
And people used to moan about the 27 mHz merchants.
AB
go away headcase .........
No Mains is ac. If you have leakage it is normally capacitive. DC does not pass through capacitors.
Capacitors in fact are used to block DC and pass the ac component.
You may have a few class C amps that use this feature.
Now this is a difficult concept, so stay with it.
Your LNB will require a Voltage of around 18V DC.
Between the braid and inner, you will measure 18V DC.
The 18V DC can be present on a cable that is 70V ac or more above ground.
Grabbing a humble spud would enable someone with a brain cell to identify the polarity and where the ac component was introduced.
Do you go on air at all?
Does the nice man at the shop show you how to tune a wireless in?
AB
Was it something I said :-)
The RSGB has a lot to answer for!
AB
I would agree with that but then again you would never have got your M3 without them...tee hee
you are a sicko ......dead simple each receiver is providing the voltage to the lnb and there is a voltage on the outer of the F plugs at the lnb so must be the lnb that is doing it and giving no horizontal signals to either receiver....no?...and you know where you can stuff your potatoes....
or are you a class B M3 ? ....
I live nowhere near Basingstoke.
If that's a reference to one of those new licences, I'm afraid your cynicism is wasted. I lost interest in amateur wireless a long time back.
At about the same time that equipment started to come in cardboard boxes and technical "discussion" consisted of idiots comparing colour, power or some other equally mundane and pointless parameter.
AB
Yes indeed, I see it all now.
Have you any more of these LNB's, it sounds like you have encountered a source of perpetual motion.
AB
Surely there must be lots of experts on Sky in your trailer park?
Not a lot of use without an interpreter.
If the LNB supples the power to the cable a Sky expert isn't a lot of use.
One of those Crystal danglers would be more appropriate, you know, start a crystal swinging on a string.
Either that or prayer is good in such situations.
Daleks are still the most plausible really, they allow the laws of physics to hold, no matter how unlikely the scenario.
AB
good man...now go away ...thanks
all trash I'm afraid .....
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