Octo lnb with multiswitch

[rolfw]

I had a problem with an optima switch with quad LNB on a Penta 85, reckoned it was possibly too much signal for the multiswitch and it didn't have good enough isolation between ports when using a quad, it was however fine when I put a Quattro LNB on with slightly higher power. Try just connecting the Vertical high port of the multiswitch without any others connected and see if the Sky digibox shows a signal.

 

[barrykap]

Nope.

Tried that with just one input but not a dicky-bird comes through to the Skybox.

I have given up on getting it to work with the Skybox.

At the moment I am using a 'hybrid' connection. With two direct feeds from the Octo LNB straight to the Skybox. Plus four feeds from the Octo going to the multiswitch. From the switch outs I am taking off two dual feeds to the Pannybox and the Foxsat, plus another single feed to my TV, plus a single feed to another Technomate Satbox (via a 4-way Diseq switch) which I use just for SatRadio. All of these outputs from the multiswitch work fine with 100% signal to everything. Just the bleeding Skybox which is the trouble (grumble grumble).

Barry.

 

[tesla]

Multiswitches with Q2 technology can use a quad or Octo as well as quattro ralph, as mentioned above.

I don't know this Q2 but it's doesn't seem to be something super, advanced, hi-tech. Each input of the multiswitch sends the appropriate voltage and the 22kHz tone (if necessary) to the LNB ports, so simple. This feature is available to the 4 Sat IF amplifier SBK 5503 from Spaun.

Does the switch have a manual button or anything to make it work in Quad LNB mode?

This kind of switch is necessary. Anyone interested in connecting a multiswitch to Quad/Octo should search all the companies: spaun, Televes, Ikusi, Johanson, Wisi etc etc

mmmm, if one of the other receivers works fine on the exact same ports but the Sky box doesn't, I expect that it is some kind of "issue" that no-one really knows the answer to.

This is very strange "issue". Perhaps it would be necessary to measure the actual value of the voltage and the level of the 22kHz (this measurement requires an oscilloscope). The 13V are not supposed to be 13,0000V, a small deviation is acceptable.

Some Freesat box have been reported to have probs with some quads.

The only i can think of is the power consumption (receiver's DC out at the LNB connector), the milliamperes that the LNB requires. If the receiver is connected directly to the LNB the power consumption is about 100mA, if it is connected to a multiswitch the power consumption is much lower.

Let's see how an octo can be connected to a multiswitch. The picture shows the whole circuit. You need a power inserters, 2 22kHz generators and 2 power supply units (13V, 18V). This circuit works with any multiswitch no matter if it is Q2 or not, having manual switch or not etc.
The Spaun part numbers are FSW30F for the power inserter and SG22F for the 22kHz generator. These components are not something rare or special. You can search the sites of other companies like Televes, Ikusi, Wisi etc

 

[barrykap]

Thanks Tesla, for your interesting comments and suggestions.

Unfortunately I have no test equipment to do that sort of thing and in honesty I don't feel I OUGHT to make all that effort to get something that ought to work, work. :-)

I feel the problem lies with Sky only and maybe their design will not supply the LNB voltage you mention, which is surprising considering the ideal application for a multiswitch would be for distribution of Sky feeds.

I would ask them the question but I know I would be wasting my time as there is not a '£' sign in front of it so they will not be interested. :-)

So I will just have to cope as I am doing.

Many thanks.

Barry.

ps. To make what is already an excellent circuit diagram even better I think the two lower power inserter outs should be labelled 'Vertical'

 

[tesla]

ps. To make what is already an excellent circuit diagram even better I think the two lower power inserter outs should be labelled 'Vertical'

You are right (a side effect of copy/paste).

 

[OldBen]

It must be something between the switch and the skybox for sure, its strange though as I helped a friend a while back with his dish and switch, and I think he has the same amstrad HD box you do and it worked ok, think the switch was an antiference or something though, not the "Optima 5x12 Q2 multiswitch" you have.

Have you checked the manual for the switch? Lots of switches have more output (db gain) on some ports that others, the idea being you put the longer cable runs on the higher output, and the shorter runs on the lower gain outputs. See where your sky feed were connected, if they were 1,2 try 11,12 or vice versa. Might be too much signal maybe for the sky box? (doubt its too little based on your other comments). Easy check anyway, sounds like its bugging you as it would me why it does not work as expected ;-)

 

[Leeh]

Hi
This thread looks similar to the problem I'm having with my multiswitch install. I have an octo LNB, 2 lines feed a sky+HD box, 2 lines feed a sky+ box and the other 4 go to an optima 5X8 Q2 multiswitch in the loft. I couldn't get a signal on a digibox in the bedroom from the multiswitch via a SAT/TV diplexer in the bedroom. I took the digibox upto the loft and connected it directly to the feeds to the multiswitch(1 at a time), and got a good signal from all 4 of them. With the listings already stored in the digibox from the direct feed from the LNB, I connected back up to the output from the multiswitch and received the expected channels, however, on the signal test page I still get no signal strength or quality and if I unplug the digibox from the mains I lose all the channels and the digibox displays a message "No satellite signal being received".

Any ideas as to the way forward would be greatly appreciated.
Lee

 

[PaulR]

Has the Digibox been left disconnected for a while? It might have missed an over-the-air firmware update or two.

 

[Leeh]

The digibox was left disconnected for a short while but I forced a software update just to make sure that wasn't the cause. Unfortunately still no joy.

 

[Topper]

Perhaps it missed more than one!
Did you try again?