Ber/Sig/Snr and what they mean

[gav12345]

so as i said originally

A splitter and an attenuator are different items, a splitter will have NO db figures on it,
an attenuator will, they can look the same as each other but an attenuator can have 2 outs
(looks like a splitter but its NOT) if it says something like 3db or -6db or the like it IS an ATTENUATOR,
NOT a SPLITTER and should not be used as a splitter or you may get jerky or no picture

 

[loady]

i think the actual loss from a splitter is 3db and as said is unavoidable

 

[gav12345]

i think the actual loss from a splitter is 3db and as said is unavoidable

its about that and thats why you dont need any more then that and to have both is a no no thats why its better to check it out


cheers

 

[mgb]

A item with one in and two outs is a splitter. On some of them the signal reduction is printed on the label. If nothing is printed on the label doesn't mean the producer are able to change physical constants.

 

[gav12345]

some so called splitters have higher db value than others the lower the better of course

 

[mgb]

Typical is 3db signal loss on a splitter with one in and two out and lower then about 2.8db is technical not possible on a unamplified splitter with 2 outs.

 

[BrianA]

:Cheers: Gav12345,I changed the attenuator for a splitter and now I have a Dbox that doesn't freeze or lose channels.
:mexican:

 

[Griz]

Hi Gav i dont know if i should post this here!!! anyway i have a problem with a friends box i know it works in my area fine but when i take it to his area n*l it does not have a picture the epg & clock is there some channels get sound but the ber is over 2000!! is this the problem if so how can i get the ber down ive tried taking the modem plug out but the ber is still the same the sig & snr are fine!!!! can you plz help!!!! :Cheers: Griz

 

[wenglishboy]

im not sure if i should mention this heck im not even sure if its the case but my ber and snr are all varying depending on the channels i watch... and i have perfect picture on all channels so i guess either my dox is 1 in a billion or the ber sig and snr all add up to as alex ferguson put it the other day " absolute boll*cks"....all im saying is my dox dont seem to care for these stats much

 

[mgb]

Every driver version deliver other numbers and you can only compare 2 boxes which are using exact the same driver version.

 

[zakhan]

hi gav,
i've sent u a msg earlier, could you pls reply. when i flash sposter in my dbox2 it scanned all chanels but only asian chanel workds rest of the no. when i flash pacino all chanle works but no asian chanels. pls help.

 

[gav12345]

hi gav,
i've sent u a msg earlier, could you pls reply. when i flash sposter in my dbox2 it scanned all chanels but only asian chanel workds rest of the no. when i flash pacino all chanle works but no asian chanels. pls help.

sorry m8

i had a big list of pms today and i deleted a lot of them i am sorry

with the pacino scan with fast scan off and scan for all services and wait untill it finishes

then check the following bouquet andere and look for your channels in there or look into the services----bouquet editor and have a look in there

has to be there somewhere lol


cheers

 

[Munkey]

Thanks for all the signal info. Helped me greatly in getting started.

I'd recommend a signal booster to anyone having problems with jerky picture.

 

[hunnimonstr]

complete newbie having problems.

Hi all,

Can anyone please advise? I have just got a Dbox2, and am having a few problems.

On opening the box, I pluged it all in, First stop was to change the IP address and install the box on the network, which went smoothly. however the network test failed to ping the dns address suppleid by my isp, and failed to resolve a web address dboxupdate.berlios.de

However as my need was only to establish an ftp session to copy the system.xml file i have not given the dns lookup failure any futher thought.

I copied the provided system.xml file out to my laptop, and downloaded and extracted the recomended file for my area, shut down and restarted the box, and nothing, channels were listed but none were found. I performed scans over the two providers listed on the sym6889 and sym6592 (from memory), with fast scan off and manual scan off. - no chanels found.

I have 3 cable feeds into my home, 2 for analog/digital tv, one of which has an old analog box plugged in, and a third for my cable modem.

I tested all 3 lines both with the modem attached and without it attached with the same result.

After finding reference to your BER/SNG/SIG post, I went outside to find my 3 cable feeds in are split through a box labled splitter but with -6.5db lables on each of the outputs.

With the BER/SNG/SIG display current on the dbox, I tried with new coax a connection direct from each of the outputs directly to the dbox2 and also directly in from the feed in also, all gave the same BER/SNG/SIG readings

BER=4k, SNG=11-12k, SIG=62k

I did not shutdown and restert between taking these readings as I assumed it was a dynamic display ????

even showed the same values when not connected at all.

Last thing I tried was to reinstall the analog cable box in the loop prior to the dbox2, so the setup is as follows:

cablefeed- into -analog cablebox(in)
analogcablebox(out)-into -dbox2(antenna)
dbox2(out)-into -sky(RFIN)
sky(RFOUT)-distribution amp
distribution amp- TV's

The result is I can recieve the analog tv channels again QVC etc, and now the BER/SNG/SIG values are BER=10k SNG=55k,SIG=62k But as soon as I attempt a service scan, it fails imeadiatly with a transponder scan fail message.

The seller has offered to check the box out if i send it back to him, but I would rather get to the bottom of the issue first so I can say I think X is wrong with a degree of cirtainty, if only to save the postage fees to have the box returned at my expence as aok.

I thought it could be an antenna connection problem with the box, but if it is looping through the analog cable feed ok then this is less likely????

ps I have also double checked all visible cables, and used new coax to test the line from outside the house.



please please take pity on a newbie

many thanks in advance

HM

 

[Fergalsworld]

Very detailed post but you forgot to mention the most important thing.
What image is on the box.

 

[lloydberger]

Great info for the new people to the dbox scene..

Great work.....

im new n its helped me : mr ed :

thanx
lloydberger:Cheers:

 

[Devilfish]

@hunnimonstr

Your SNR value is too low! Needs to be above 55,000 before you'll get any channels and needs to be about 62,000 before you'll get all the channels.

 

[firefox1965]

Hi m8, i have nokia box that doesn't like a weak signal, have found pacino v1.0 and sporster 1.76.3 image run best out of about 10 images i tried.

"whats good for one isn't always good for another"

 

[hunnimonstr]

Hi Thanks for the input, and sorry for the vital ommisions.

The box came with sportster 1.73 uk05, after I first had problems the supplier suggested I try sportster 1.73 uk01. I flashed that image without any problems. This gave me 2 different scan options, Bruteforce, and Fast.

I opened the BER/SNR/SIG display on the dbox2, the graphic led me to belive the test was dynamic. so while running I attached the dox to both the native feed into my home thro new coax out of the window, and while I was there I also tested on the unused link outside my neighbours house.

and performed scans on each feed. The BER/SNR/SIG did not change significantly through the test, +/- 1k... even when disconnected completely.
Should I have restarted the box between tests????? cos I didnt.

ps both cable modem and analog box both work on the next door feed also??
In fact I think i am still running the cable modem over that link ...

The supplier A german ebayer, will take the box back for testing, and is offering a refund or replacement if faulty, but I would like to know for sure before i pay the postage.. Cant fault the service from this ebay seller..he answered my emails within mins and pointed me here..

I plan on taking the box to a plas place to test on a live digital cable feed.. hopefully this will shed some light on whats going on.

I may get the time to repeat the test for BER/SNR/SIG with shutdowns between cable changes, tonight, but then again I may take an evening off dbox debugging and have a beer instead.

Thanks for all the suggestions guys, and thanks for the suggested images Firefox, I will try them, fingers crossed eh..

 

[hunnimonstr]

Cheers devilfish, thanks for the interest, I understand this but what puzzled me was the similar values even with no cable attached..... and I want to confirm there is a hardware prob before I try and get a replacement. bareing in mind I didnt shutdown the dbox to change cable feeds just left it running on the signal display? so am begining to doubt the validity of the test.