ATTENTION All AV Receiver / Processor Owners with STB connection.

[rbalagopalan]

I just happened to read the Thread "Attention ONKYO owners" which talked about Receiver failure. In this context I felt opening a separate thread would benefit / safe guard the AV Receiver / Processor of many users.

In the wake of HD transmission of Satellite channels we all must have gone for HD set top boxes and duly hooking it up with our AV components to benefit from the 5.1 Audio transmission by the channels.

Please be aware the STB is more vulnerable for Lightning strikes and throwing surges to our much costlier AV Receiver / Processor. This can directly result in failure of Power Board, Main Board, HDMI Board and some cases Display Board too. Imagine the extent of damage, my god unbelievable isn't it :sad:

WHAT IS THE WAY OUT?

Only copper involved connection which can conduct current can cause this damage. So do not connect your Receivers / Processors with the STB by HDMI and CO-AXIAL cables as they use copper to transmit signal.

As all the HD channel providers transmit only 5.1 Audio, Optical cable is more than enough to transmit 5.1 signal. Hence Optical connection to the receiver from STB is harmless.

HDMI can be given directly to TV, of course now TV becomes vulnerable but it is inevitable and to an extent TV can tolerate this I think so, as all TV manufactures would have foreseen and faced this long ago and have some protection built in. If any one can throw light on this it will be help full.

Even assuming some thing happens to TV it is lot easier and cheaper to restore it than our AV components.

Thanks

 

[Vinod.R]

In the ole days, a lightining guard would be used to protect the TV which used to get the bare RF cable to the TV. I think this might be useful in the present scenario?

 

[rbalagopalan]

In olden days when Antennas were used the other end of the RF cable which is connected to the TV there used to be a connector with a mini Balloon transformer in it, which will Isolate the surges transmitted by the Antenna from the lightning strike. Now introducing any Isolation is ruled out as the same will directly affect the Video and Audio quality.

 

[Naturelover]

Good topic for a separate thread.
Has anybody used something like this? Any opinions?
Quoted for Rs 6,500 for single phase version.

 

[Subcenter2009]

Dear Mr. Balagopalan,
I propose a solution to this problem which has many another benefits. This is how I am connecting my Home Theater, you see..
Try connecting your HD set top box via HDMI to your new LED/ Plasma TV.
Try connecting your DVD/Blu-Ray player to your LED/PLasma TV via HDMI too.
If your TV has a Toslink (Optical) output, then connect your TV to the AVR via Toslink.
Advantages are,
(1). AVR is protected from lightning and violent power surges.
(2). Need not switch on the AVR every time while watching TV or DVDs.
(3). Can control the volume on the TV from Set Top Box remote and the TV remote.
(4). TV remote volume does not affect AVR volume and can be muted seperately.
(5). Most importantly, you can get 7.1 surround (Usually only Dolby Digital) from your USB pen drives and HD set top box too with this connection method.
So, If you are planning to buy a new TV, Please buy a TV with optical out.
Yours,
Subcenter2009

 

[rbalagopalan]

Dear Mr. Balagopalan,
I propose a solution to this problem which has many another benefits. This is how I am connecting my Home Theater, you see..
Try connecting your HD set top box via HDMI to your new LED/ Plasma TV.
Try connecting your DVD/Blu-Ray player to your LED/PLasma TV via HDMI too.
If your TV has a Toslink (Optical) output, then connect your TV to the AVR via Toslink.
Advantages are,
(1). AVR is protected from lightning and violent power surges.
(2). Need not switch on the AVR every time while watching TV or DVDs.
(3). Can control the volume on the TV from Set Top Box remote and the TV remote.
(4). TV remote volume does not affect AVR volume and can be muted seperately.
(5). Most importantly, you can get 7.1 surround (Usually only Dolby Digital) from your USB pen drives and HD set top box too with this connection method.
So, If you are planning to buy a new TV, Please buy a TV with optical out.
Yours,
Subcenter2009

Thanks for your suggestions, but you are not achieving anything special instead you loose something.

1. Even in my suggested way you don't have to switch on the AVR until unless you want surround sound. You can control TV volume as indicated by you.

2. Connecting the Blu-ray player to TV and then to AVR via Toslink is not suggested as Toslink or Co axial can carry only 5.1 and not true 7.1. So your point of enjoying 7.1 is ruled out.

3. More over players do not produce surges.

4. Over and above you loose the luxury of video processing offered by most of the AVRs

5. Most of the TVs with Optical out are with DD & dts decoders why to spend that extra money as long as you have AVR.

So your suggestion is ok only for AVR that does not have video processing, DTS HD MA and DD True HD and person still watching only DVD content or 700MB to 4 gb data content from pen drive.

Whereas most our forum members are far informed and installed HT owners.

 

[haisaikat]

I have my STB connected via HDMI to TV directly so that I do not have to turn on my AVR (standby) everytime I want to watch only STB+TV. There is another Toslink connection from STB tpo AVR for 5.1 sound. However I think this does not help everyone since not all DTH providers use Toslink for provising 5.1, some like Tata Sky I remember has Coaxial for the same. Also every AVR has video out to TV via HDMI again, so if TV get struck via STB will that still not have potential of Damage to AVRs?

I think still the best way to protect lightning is to disconnect everything during lightning.

 

[rbalagopalan]

I think your post TATA SKY STB having only coaxial output solves the puzzle of the points discussed in the 2nd page of the following thread.

http://www.hifivision.com/surround-...o-owners-prospective-buyers-2.html#post543265

Please go thru that thread.

R. Balagopalan.

 

[spirovious]

I have connected HDMI to TV and made optical connection to AVR.I have airtel box which has optical out.Most of foreign STB has optical digital out mostly due to same issue.
Some of entry level AVR too come with optical input more than coaxial.

 

[musicbee]

All of my Onkyo's have coaxial and optical inputs so I don't see choice of input being an issue.

Now for a noob question. Won't having a surge protector help in case lightning strikes? Or any similar equipment that we can use to connect the AVR, the TV and even the STB?

 

[rbalagopalan]

The surge protectors are for Power line protection ie any surge that happens in 220v input supply but the topic / problem here is the surge transmitted by the dish of the STB from lightning strike or any exposed power cable landing on the dish etc., Some surge protectors do have RF cable in and out which can filter the surges.

 

[prosenjit]

of course belkin and stab is mandatory..or more expensive isolations
uske saath saath
being extra protective this practice can be introduced
1.avoid usage during lighting/thunder..be it a exciting climax..rocky smashing clubber
2.unhook stb output hdmi point..or the main coax into stb input... from dish..before sleep and again hook before next day use..may seem overly done..but I maintain this

it is right the stb is main culprit than supply voltage

 

[Dirac]

I still cannot agree with the issue here.
The stb is not a conductor which directly transfer input voltage to output current.
There are various semiconductor elements inside which eventually produce non linear behavior.
For example the input section of the signal amplification circuit uses OPAMPs with high input impedence, I.e draw zero current from the signal source. Only voltage is amplified. That too if the input voltage is more than its operating voltage, it simply breaks down. It results in an open circuit. The surge has nowhere to go .
The STB might go for a toss. But won't pass on the input surge to the output like a copper wire. And I am only talking about input section . There are various other elements that isolate themselves using high input impedence sections.

So I am not seeing a need to fear at all.

 

[rbalagopalan]

I still cannot agree with the issue here.
The stb is not a conductor which directly transfer input voltage to output current.
There are various semiconductor elements inside which eventually produce non linear behavior.
For example the input section of the signal amplification circuit uses OPAMPs with high input impedence, I.e draw zero current from the signal source. Only voltage is amplified. That too if the input voltage is more than its operating voltage, it simply breaks down. It results in an open circuit. The surge has nowhere to go .
The STB might go for a toss. But won't pass on the input surge to the output like a copper wire. And I am only talking about input section . There are various other elements that isolate themselves using high input impedence sections.

So I am not seeing a need to fear at all.

I am also not able to digest this, some times we have to swallow a bitter pill for cure.

Please read the post No. 7 by member haisaikat and my reply post no. 8 to it. these posts have been made at 2.30 pm on 3rd.

Now see my post no. 17, post no.18, and my reply post no. 19 in the following link, which is self explanatory. These posts have been made at 10.30 Am same day.
http://www.hifivision.com/surround-...o-owners-prospective-buyers-2.html#post543265

In fact the above thread only mooted me to make it as a separate thread so that it attracts most of the users than the topic being in some post in some other thread.

 

[newvirus2008]

Hello all,

Watchdog techniques like hooking/unhooking every time can be a pain to most people and are not very robust either, as there is always a non-zero probability that one forgets to unhook after use.

For the non-technical guy, I would suggest a coaxial to optical converter.

For the DIY fellow, the TOSLINK transmitter part no is TOTX147.
Please note that although both coax and TOSLINK carry same data, the amplitude of the coax signal is significantly lower (0.5V) while TOTXs are 3.3V parts. An adjustment is necessary.

By the way, I use separate circuits for TV, as I prefer NO STBs anywhere in my signal chain.

Regards.

 

[Dirac]

What is the probability of such a thing happening even if we assume that stb will pass on the lightning pulse to the AVR?
Is it not too much of paranoia to avoid using hdmi cables to avrs just because of a rare event in the Universe?
We are trying to protect our hi-end avrs which will become low end if connected via optical cables.
If such a rare event happens and the Universe picks up the most unlucky guy with a high end avr (I know that only 2 percent of avr shoppers would go beyond 50k) , then let it be so. The guy would get a chance to upgrade to the latest, atleast on this pretext..

 

[newvirus2008]

Hello again,

If you are referring to the HDMI vs optical issue, then I think the fibre optic channel has bandwidth big enough and BER small enough to carry a compressed bitstream like DD or DTS.

I have not heard of any digital cable / SAT channel having 7.1 audio.

Also, I have been hearing about discussions on "coaxial beating optical" but still believe that it is just like another audiophile speaker wire that has "zero inductance".

My reply was oriented towards very lazy people who are so scared that they are ready to take precautionary measures.

Regards.

 

[rbalagopalan]

Hello again,

If you are referring to the HDMI vs optical issue, then I think the fibre optic channel has bandwidth big enough and BER small enough to carry a compressed bitstream like DD or DTS.

I have not heard of any digital cable / SAT channel having 7.1 audio.

Regards.

I Concur this.

R. Balagopalan

 

[Dirac]

No. I was not highlighting hdmi vs optical for Dts 5.1.
Down the line Stbs might deliver 5.1 Dts MA hd sound and then optical might not be an option. I am saying this because we might see 4k transmissions in future, may be after 5 years or so. If they then have the bandwidth on a satellite channel for 4k , then they might also give hd audio.
And even in such far future cases, lightnings will continue to exist.
All picture processing and audio processings of any hi end AVR, Tv, or bd player etc etc are built around hdmi capabilities. Example is the PQLS tech of some Pioneer AVRs that reduce jitter in audio of the source over hdmi. Many AVRs upscale, video received over hdmi only.
And HDMI standard itself is evolving continuously for providing extra services integrated into one interface.

Some worries are best left unattended. And this lightning thing exactly falls into that category.
Let me add another worry like this one.

Solar flares that erupt from Sun periodically, are highly energetic particles that potentially can short all electronic connections on a satellite. So the satellites have protective shields.
What if they pass straight through the atmosphere and enter our AVR? There is definitely remote chance as people are talking about even power disruptions in such a case.
And shall we worry about shielding our electronic equipment to meet this eventuality??

 

[gauthamnaidu]

Lightning Rod Protection Installation details

its a badly made website...

but the images in the bottom might throw some light on constructing your own lightning conductor/protector system...

if anyone has done it...please let us know with pictures..

instead of worrying about the connectors and stb terminals.. lets move on to think what else can be done??

im looking for more..planning to construct one for myself using an engineers help...