H & V switching openbox s10 Problem

genius08

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Right i have a very strange issue with my Openbox s10

On some transponders they are fine and open ok where as others like argos tv or gold will not work.
Sometimes if i set it to 9750 i can get V's to clear but universal doesnt want to know half the time.

Here the strangest thing we have a dm500 aswell and if we turn that on then i lose even more channels!!!!
that box is connected same as me to a sky quad lnb, except the dm500 is on a diseqc switch and i am just direct into the quad lnb.

Ive read loads and loads of forums and webistes on about 'Loop through' and i do not think it is that as i have disconnected at the dm500 the wire and i still have problems on certain transponders (no signal)

im yet to remove the connection directly at the lnb and then do another test.
if you ask me these openboxes are a pile of rubish and the firmwares need sorting properly as it seems to me they have a switching problem for v/h!

if its not the openbox being faulty then is it the lnb quad thats working incorrectly? i.e not switching properly?

Have any of you lot got an openbox and another box (not sky box) on a quad lnb and are ok or have issues like me?
or even tried using a 1 port lnb on its own?

I really do not know what to do apart from buy another minidish just for myself upstairs on its own lnb or what.

HELP!

thanks.
 
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Had something like this a while ago, certain channels not working on one polarity, turned out to be the LNB, it worked on another box but with one box the 18v was a little low by the time it hit the LNB, changed to an inverto and it was fine.

Frenchman
 
Have you seen my solution in the 'Openbox S9's LNB Polarisation Voltage Problem' here -

_http://www.satdownloads.co.uk/index.php?topic=26114.0

This has continued to work satisfactorily.
 
Have you seen my solution in the 'Openbox S9's LNB Polarisation Voltage Problem' here -

_http://www.satdownloads.co.uk/index.php?topic=26114.0

This has continued to work satisfactorily.

could you post this solution on here please instead of a link to another forum that requires us to register to see the solution you have mentioned

edogg
 
could you post this solution on here please instead of a link to another forum that requires us to register to see the solution you have mentioned

edogg

I agree but luckily i regged years ago.

however i will quote the essential post myself for all to see, and then also a post from me explaining the test.

If anyone gets a similar problem the answer I came up with is the insertion of a diode between the Openbox 'LNB In' and the LNB - anode to 'LNB In'.

This has been working satisfactorily for a week now.

The voltage drop produced by the diode is quite small - about 0.4V but is enough for the LNB to interpret the polarities correctly.

The main board in the Openbox uses surface mount devices so - for me anyway - makes it a no-go area for doing a proper alteration to the dropper resistors.

Regards.

So what i did was get an old baccy tin and drill in and affix 2 chassis F sockets onto it and then solder a diode between the 2 points, then connected the aerial wire to one socket andafly lead to the other going to the box and its working so far.
at 1st i tried a 27 ohm resistor but as soon as i turned the dm500 off downstairs id have no channels upstairs on the openbox s10.

the diode appears to work on every channel with dm500 on or not.

heres a couple of pics of the DIY openbox project lol

aaaa001b.jpg
aaaa004.jpg
 
Sorry about the link. I was unaware that that forum required registration before reading!

Does the diode insertion resolve your problem completely?

Your 'old baccy tin and drill in and affix 2 chassis F sockets' is exactly the same way I used!
 
Sorry about the link. I was unaware that that forum required registration before reading!

Does the diode insertion resolve your problem completely?

Your 'old baccy tin and drill in and affix 2 chassis F sockets' is exactly the same way I used!

as far as i can tell now with dm500 on or off the quad makes no difference to me now, gold and argos tv used to just say no signal as soon as dm500 came to life, but now all chans remain on. so theory is this, the dm500 on the quad lnb is leaking voltage back down the quad lnb/coax to the openbox, openbox tuner is either craply built or is simply missing a simple diode when built? apparently if you supply the openbox with just 1 connection on a quad lnb then its ok, or a single outlet lnb is ok. some say the slope satellite booster helps but surely that would worsen the voltage even higher? my understanding of a diode is it lets power 1 way only, so thats my box going to the quad lnb to power it, anything trying to come back down the wire is cancelled out by the diode! ideal fix for the openbox s10 and probably s9.

It was my fathers idea to use the old baccy tin as you need the earth between the two sockets.

Last night i had a brainwave, use strip board and wires to do the same thing, as long as you solder earth to earth on the socket and then the annex signal pin to other pin but with a diode in between that link somehow. it could be done but for a professional method we would need to mass produce proper circuit board for the job.

if anybody else has this problem now you can simply do a quick test with a diode itself, poke that in the reciver lnb in and touch the aerial lead copper to that diode, and voila itll work for as lng as you can be bothered to stand there holding it. then get a baccy tin and 2 chassis sockets. luckily for me i had some old pace tuners from vm boxes and reused them accordingly!

Same mind think alike eh cascara!

a resistor only worked when the dm500 was on so that was a fail.
 
if anybody else has this problem now you can simply do a quick test with a diode itself, poke that in the reciver lnb in and touch the aerial lead copper to that diode.

Good - just add a note to the 'quick test' - the cathode of the diode (red banded end) must go to the LNB.
 
cascara,

you seem to know your stuff, what diode would be suitable to buy from say maplins i looked on there site what value do you reccomend
 
cascara,

you seem to know your stuff, what diode would be suitable to buy from say maplins i looked on there site what value do you reccomend

Just replied to your PM with my suggestions.

If you get a result please let us know what diode worked for you (the diode I used was unmarked).
 
Just replied to your PM with my suggestions.

If you get a result please let us know what diode worked for you (the diode I used was unmarked).

cascara,

i have 2 openbox's will i have to do it on each box and also can you tell what diode it is please.
 
@rio

Did you read this thread and thought it meant every box needed to connect to its LNB via a diode?

Use of a diode to drop the polarising voltage is only needed if you are missing the 'V' (vertically) polarised channels.
 
Well 1 box will show some hd and normal the other does the same but vice versa
 
@rio

Whether the channel is in HD or SD makes no difference to the box putting out the correct polarisation voltage so if you cannot see some HD channels then the problem is caused by something else.
 
Hi friends, is there any update as to which diode is best to use?

I am having many problems with openbox s11 (5 boxes ALL same prioblem)

Also is this not the same as using an in-line slope amp?
 
It's only a problem with universal lnbs,standard ku linear work fine.
I think it's more of a problem with the 22khz signal that the universal uses.
I have a long run from receiver to lnb,so you think that would compensate for the higher 13v but it doesn't.
 
Hi friends, is there any update as to which diode is best to use?
I am having many problems with openbox s11 (5 boxes ALL same prioblem)

Unfortunately it is not possible to say which diode is 'best to use'. Each box and its LNB will be slightly different. At Post #10 I did ask jakemuk1 to let us know which diode in the 1N4001-7 series worked for him but no response. The first one I tried from my diodes tin worked but was not marked.

When I first reported this problem I was met with disbelief and the recommendation to buy a new LNB! My box (an S9) was the only one at that time to have the problem - since then a few more have appeared. I am saying all of this because you have 5 boxes with the problem. Do the 5 boxes have their own LNB's? If they have all been tested on the same LNB then I would question that LNB if it had never proved itself on a different make of box.
 
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I had the same problem with certain HD & SD channels missing, but, its sorted now thanks to Casacara who I'd pm'd on the subject, I used a 1N4001S diode from Maplin (product code QL73Q), following the posted instructions from Genius08, made sure the grey band on the top of the diode went to the LNB and it worked. Many thanks to both Casacara and Genius08 for the info.
 
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