Community system

[geoff lee]

HI got a problem with our system, we have a 2.4 prime focus, invacom quad lnb , a golden interstar multiswitch, a problem occured a few months back, the channels on h low were unwatchable if we disconnected the input to the h high we got h low back, we tryed running a replacement cable to h high still no good, we were then told its a fault with lnb , so we changed the lnb and had same problem, could it be a falulty multi swich or is it a question of balanceing the signals could a stronger (h high) knock out a weaker ( H LOW) is there any thing avallible to weaken the stronger signal, another strange thing is 12523 v (SOLAR RADIO) is not there at all no signal and this is normally strong you can get this on a 80cm on the costa blanca, on ideas what going on thanks any help would be good

 

[Huevos]

Sounds like the switch could be faulty, but would need to look with proper test gear to be sure. 12523 V works fine for me.

 

[rolfw]

Not sure how good the Golden Interstar multiswitches are (apart from being very cheap), may be a problem with bad isolation between ports. You could try a line amplifier on the H Low cable, or perhaps attenuate the H High, most good satellite suppliers will sell IF attenuators.

If I was changing cables, I would probably have upgraded the H Low cable, perhaps to a higher spec or larger core version.

 

[geoff lee]

hi thanks for replys, sorry if i posted in wrong section attenuate there is a line amp on h low, will try a attenuate on the h high i take it that will weaken that signal, i used to get 12523 v on my own 80cm dish no prob , but have now focus this dish on badr for the film stations since we had the 2.4 communal dish installed, cant understand why some signals which should be strong are so weak about 25% (quallity) 0n the horizon signal meter where other v high and v low are 100-95 % may be just a multiswitch thanks geoff

 

[Huevos]

Just thinking out loud. In Playa Flamenca a 2.4m dish on 2D horizontals is right at the "cliff-edge" or beyond for any lockable reception anyway. Horizontal high is the opposite; signal is colossal. You need to know if the cross-talk is in the LNB or the cabling/multi-switch. Just pulling the HH cable out doesn't prove either way because pulling out the cable powers down that section of the LNB. On the other hand if the HH cable were pulled out and then a 12 volt source were applied to that port of the LNB to keep the HH section of the LNB active this should conclusively prove if the breakthrough is happening in the LNB or the cable. If the breakthrough is internal in the LNB adding attenuators to the cabling is going to do nothing.

 

[geoff lee]

hi huevos i think i understand, this is the second invacom lnb we have fitted and still same problem, signal is on cliff edge as you say, bbc2 3 4 channel 4 comes in about 1pm goes off about 11.30 pm, but with the h high connected you get picture break up all the time, i will have to power up h high at the lnb as you have said to be sure its the multswitch and not the lnb. is there better multi switches with less "crosstalk" you can suggest, what speck should i be looking for, the local sat installers dont seem to be that good thanks again

 

[Huevos]

i will have to power up h high at the lnb as you have said to be sure its the multswitch and not the lnb.

You need to track down the problem. If you just change things in the hope that you will find the fault it is going to end up costing you a lot of money.

Can you try 11104 H 27500 2/3, and see if you can receive anything?

Other way to check is just bypass the switch. Disconnect HL and your down cable at the switch and connect them together with a barrel connector. If the fault disappears then the fault was the switch; if it doesn't it must be LNB or cable.

is there better multi switches with less "crosstalk" you can suggest

If it is happening in the multiswitch you just need to attenuate the signal before the switch, as suggested by Rolf.

hi huevos [...] the local sat installers dont seem to be that good

A few of them are ok :-thumb1

 

[geoff lee]

ok thanks i will try that next time im there, in uk at the moment will report how we get on, thanks everyone for the help geoff