snowy cracly picture,help please

kmb

Hi all,my setup is:
southcoast tv aerial & rte aerial going into 2 aerial boxs on pole for joining 2 aerials into one.This cable goes to power amplfier...cable off to sat reciever....cable back upstairs to hotpress distributer to 5 tvs.
Now about a month ago terrestrial tv reception went so first went on roof changed bottom box as it was water logged,no improvement,so changed power amplfier,perfect.
Now picture has stared to get snowy on all channels inc.the sky channels.Did find plug fuse blown in amplifer,changed it still snowy.

Question is,if the power amplifier is faulty would it affect the sky recption to the tvs around the house even though it is entering the loop after the amplfier?
Or do i start to look for damaged cables?Or could it be the distributer going down?
One thing i had done was use the 9v from the sat reciever as the feed to the distruter in the hotpress,was this wrong,could it cause a over supply power of power in the system,chaging this now made no difference so is damage already done?

regards


kieran

byte

Well, behind the Skybox, there are 2 RF outputs, RF1 for the nearby TV, and RF2 for distribution to other TV(s)

Can you assess what wires go where on the mast, as you say there are 2 boxes, and 2 aerials. I'm assuming that one box is a combiner, and the other is a masthead amplifier which feeds a Power supply unit (and then goes to Skybox).

Have you the TV above the Skybox connected directly to RF1, and if so, is terrestrial off there too?

If Sky isn't working around the house, there's a problem with wiring or else the distribution amp is faulty. No point in powering RF2 output, unless the distribution amp is compatible with Sky RF2 power. Turning on the power to feed an amp not designed for it may destroy the power supply inside the Skybox.

kmb

Hi,i think my problem is the aerial because i changed the power amplifier today in case and what happened was:
still had snowy picture even when connected direct to aerial out and tv.(ie not going around house,direct to 1 tv)
Also the sky is working error free on all tvs when i disconnected the amplier which obviously stopped the terrestrial channels.

My setup is:bbc gold aerial to rte aerial,2 boxs,down to amplifier,then to sky box,rf in,then aerial back up with the 9v output to the distribution box feeding the 5 tvs.Scart feeds the main tv where skybox is.
Other rf output goes to dvd recorder.

Is this setup okay?

I remember when i changed thelower box on the aerials that the rte cover on the aerial itself was missing,maybe wires got corroded?Would this cause the snowy breakup picture?Its likes when the aerial cable shorts between the two coppers.

Regards,

Kieran

Ps i hate going on the roof eventhough it a 25 degree pitch,Yikes!!

byte

Well you'll need to replace that RTE aerial anyway. The cable where it's connected to the dipole is well corroded, and rain water will flow down the honeycomb of the cable and into the boxes. I'm sure one box is a diplexer (combiner) and the other is a masthead amplifier. The box inside the house should only have the purpose of sending 12V or 24V power up to feed the masthead amp. You should investigate further the purpose of each box on the mast. Masthead amps generally don't fare well when they fill with water!