SPC4(F) super combiner

Shinobollo

I'm trying to combine outputs from 2 sky boxes along with UPC cable (old analog channels) into a coax feed to another room.
I know that the SPC4 will accept and filter the outputs from the two SKY boxes but I'd like to know if the SPC4 will filter and pass the UPC feed ?
I need to try and restrict the UPC output to the 20 or so channels provided. At the moment the strength of the UPC signal is preventing me using anything other than CH69 on the tv in the back room for SKY and the SKY reception is crap. It's as if the signal from UPC is blocking all the frequencies covered by CH1 to CH68 and bleeding into CH69 as well.
Can anyone tell me if the SPC4 will solve this problem for me please and allow me to use a couple of empty Channels between say 36 and 45 for the 2 SKY RF outputs ?

Peter Rhea

The reason to choose the SPC4 over an ordinary combiner is because it filters the remote signals from the magic eyes, enabling boxes that use similar remote commands to be combined onto a single feed for distribution.

You assign a remote (or remotes) to each input port & the remote signal incoming to the combiner is routed to the correct port & so on to the box concerned.

You need to pass the UPC feed through some other kind of filter. In the absence of a dedicated filter, the low leg of some group A/E diplexers should work & hopefully also remove any low frequency interference that would affect the remote signals.

Shinobollo

Peter Rhea wrote: »

The reason to choose the SPC4 over an ordinary combiner is because it filters the remote signals from the magic eyes, enabling boxes that use similar remote commands to be combined onto a single feed for distribution.

You assign a remote (or remotes) to each input port & the remote signal incoming to the combiner is routed to the correct port & so on to the box concerned.

You need to pass the UPC feed through some other kind of filter. In the absence of a dedicated filter, the low leg of some group A/E diplexers should work & hopefully also remove any low frequency interference that would affect the remote signals.

Thanks Peter. The magic eyes aren't a concern. Is there any filter / diplexer in particular you'd recommend. This has been doing my head in trying to figure it out. For a long time I thought the rf out in the sky decoder was faulty. I used to be able to loop the UPC through either one of the sky boxes but something changed in the last year and UPC are denying this point blank even though they now appear to be flooding the full spectrum.

Peter Rhea

Triax TFC3739 or TFC3537 should hopefully keep enough of the UPC signal out of the top 30 or so channels of the UHF band, while allowing all the UPC analogue channels to pass on the low frequency leg (goes down to 47 mHz).

'Magic eye' remote signals won't pass on the high leg but, since you aren't using them you can connect the Sky feed there, without any issues.

Antenna

Peter Rhea wrote: »

You need to pass the UPC feed through some other kind of filter. In the absence of a dedicated filter, the low leg of some group A/E diplexers should work & hopefully also remove any low frequency interference that would affect the remote signals.

If the problem is due to the UPC cable having signals or noise across ALL the UHF range then a LTE filter (800MHz filter) like this could also do the job to allow use of high UHF channels?

http://www.tvtrade.ie/4g-lte.html

and then using channel 65 or above (not lower) for the Sky box modulator.

This filter (or the one Peter above suggested) would go before the RF-In of the Sky box.


If the problem is downstream of the RF-in of the Sky box (such as signal overload of lower frequency cable signals) it won't be a cure.

I also replied in the cable forum too.
http://www.boards.ie/vbulletin/showthread.php?t=2056975200

Shinobollo

Peter and Antenna, thank you both for taking the time to reply. I'm not sure but I think the LTE filter might be the way to go.
As I mentioned, my setup for years was to feed the UPC analog into the "rf in" on one of the sky boxes and then pass on the UPC and sky channels combined through the rf out. Recently though that hasn't been possible as the UPC signal for whatever reason is now blocking all rf channels. So what I need to do is reduce the impact of UPC. Definitely worth a try and if that doesn't work then I'll have to look for some kind of TRI-plexer similar to Peters suggestion as there's 2 sky boxes and 1 UPC cable to be combined and passed on. Thanks again. Dec

zg3409

UPC send signals down the cable for internet, and they are all over the place.

Depending on where you live up to 600Mhz is used for analog TV channels.
See :
http://www.boards.ie/vbulletin/showthread.php?t=2056825676

So ideally block somewhere above 600Mhz, but still within range of the Sky output channel list. Beware the LTE as 800Mhz upwards will be used for mobile phones very soon which may then cause you problems.

Ideally use a cable sprectrum analyser to see which frequencies are free. Try to use a relatively low one, to avoid LTE in the future.

Naturally each of the Sky boxes need to be set to different channels.

I don't think SPC4 in particular would be of any use but any filter would want to pass up to 600Mhz. The triax TFC3739 fitted between the UPC wall outlet and the Sky Aerial in (using just the low leg and the output) should block out noise above 600Mhz before it enters the Sky box.

Antenna

zg3409 wrote: »

Beware the LTE as 800Mhz upwards will be used for mobile phones very soon which may then cause you problems.

Channel 65 is supposed to be in a guard band between uplink and downlink 800MHz LTE, so Ch 65 is hopefully OK for modulators in the future.
800MHz LTE base stations (masts) are to use the Ch 61-64 area, these channels would be most likely to be troublesome, whilst the handsets would be in the 66 to 69 area.

If there is good quality well shielded co-ax cable in use (and no plastic splitters etc) there likely would not be problems in a 'closed system' (no aerial) like above in using a modulator in the Ch 65 to 69 area (with an 800 MHz LTE filter to block cable network noise or signals in the 800MHz range) .

The Sky boxes need to be at least 2 channels apart if distributed together, say Ch 65 and 67 (or 68, or 69)

Peter Rhea

If I was setting this up for myself, & assuming the 2 Sky boxes & the UPC outlet are all in 1 place, the 1st configuration I would try would be UPC cable to TFC 3739 low leg & the combined Sky box output to the high. I would try 'daisy chaining' the Sky boxes & if that didn't produce acceptable quality, try another combiner before the TFC.

Shinobollo

Folks just wanted to say a big thanks for all your help. Finally got around to running the UPC cable through a Triax 3739 and its made a huge difference. Not perfect by any stretch of the imagination but both decoders are now watchable in other rooms and they're used primarily in the main room anyway. Thanks again. Dec