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Discussion Starter · #1 ·
Hi Guys

I was not able to find a forum that deals with powerconditioning, so I post it here, in the hope that this is the most nerdy forum avaliable 😁🤓..

All devices in my system is hooked up to a furman P-6900 power conditioner, but I have encountered issues with my cabletv box. The DTV cable coming from the outside world is not regulated power-wise, and that seems to cause issues with the HDMI output of the cabletv box, that has burned HDMI inputs on my AVR, that simply stopped working one by one. Naturally I cant be sure if lack of power conditioning of the incoming antenna cable is the actual reason, but is is the only reason I can think of?

During the day, the power can flux as much as +/- 20 volts, witch is regulated by the power conditioner. The. antenna signal is not, so therefore I am wondering if this difference can cause problems for the cabletv box, resulting in bad current on the HDMI output?

Is anyone aware of a way to power regulate a cable tv signal, so it will come “in sync” with the power of all the other units in my system?

Power is not a field of expertise for me, so sorry if I mess around in the concepts!
 

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What does "regulated power wise" mean?
+/- 20 volts seems extreme.
Where do you live?
The cable coming into the home is connected first to the cable box, correct?
 

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Although Electrical Power is carried down the Coax Network feeding your neighborhood for the various CATV Amplifiers and other equipment, there should be Zero Volts (AC or DC) between Center Wire and Shield for the Coax Drop Cable entering your premises....if there is, CALL CATV company to FIX it.

CATV Coax Drops can frequently have GROUND-LOOP problems that can result in AC or DC voltages....or HUM. First think to check is to physically look for a GROUND BLOCK that Coax Cable signal goes thru, with Shields connected to SAFETY GROUND....typically via Green Wire to Metal Box surrounding the Electric Circuit Breakers....or other approved Ground (i.e. Cold Water Pipe, Copper Stake driven sufficiently into the earth, etc.):
https://www.amazon.com/F-pin-Coaxial-Grounding-Single-Female/dp/B001I5610E

To protect your equipment, it is advisable to screw fol. CATV Isolation Device onto the HOUSE side of the aforementioned GROUND BLOCK....it NEEDS a low impedance connection to Safety Ground:
https://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias=electronics&field-keywords=catv+isolator

Note that Holland CISP-HR CATV Isolator includes a Surge Suppressor......and ignore the Blonder-Tongue Device....it's something else....
 

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Discussion Starter · #5 ·
Although Electrical Power is carried down the Coax Network feeding your neighborhood for the various CATV Amplifiers and other equipment, there should be Zero Volts (AC or DC) between Center Wire and Shield for the Coax Drop Cable entering your premises....if there is, CALL CATV company to FIX it.

CATV Coax Drops can frequently have GROUND-LOOP problems that can result in AC or DC voltages....or HUM. First think to check is to physically look for a GROUND BLOCK that Coax Cable signal goes thru, with Shields connected to SAFETY GROUND....typically via Green Wire to Metal Box surrounding the Electric Circuit Breakers....or other approved Ground (i.e. Cold Water Pipe, Copper Stake driven sufficiently into the earth, etc.):
https://www.amazon.com/F-pin-Coaxial-Grounding-Single-Female/dp/B001I5610E

To protect your equipment, it is advisable to screw fol. CATV Isolation Device onto the HOUSE side of the aforementioned GROUND BLOCK....it NEEDS a low impedance connection to Safety Ground:
https://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias=electronics&field-keywords=catv+isolator

Note that Holland CISP-HR CATV Isolator includes a Surge Suppressor......and ignore the Blonder-Tongue Device....it's something else....

Guys, thank you very much for the competent feedback! Ill try to answer the questions!

AVR is a Marantz 8802A
I live in denmark, according to my Power conditioner volt meter voltage sometimes is as low as 210 volts and i have seen 242 volts in my nabourhood. We have a transformer station very close by, maybe that has something to do with it.

Who would be the right type of person to do the nessasary meassurements, in order to find out if there is AC, DC or ground loop issues with my cable tv?

From the street, the cable goes into a distributor, feeding various antenna installations in the house, as well as my docsis router (we get internet via cable).
 

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Hello, Morton; welcome to our Forum.
All devices in my system is hooked up to a furman P-6900 power conditioner
That is a very large power conditioner; you must have a lot of equipment connected to it. I would have expected you to be using a smaller model.

http://www.furmanpower.com/product/30a-voltage-regulator-power-conditioner-P-6900 AR E

datasheet
http://resources.corebrands.com/products/P-6900-AR-E/pdf_P-6900-AR-E_datasheet.pdf

manual
http://resources.corebrands.com/products/P-6900-AR-E/pdf_P-6900-AR-E_manual.pdf

https://www.amazon.com/Furman-P-6900-AR-Regulator-Conditioner/dp/B00ZAEQL1S

Who would be the right type of person to do the nessasary meassurements, in order to find out if there is AC, DC or ground loop issues with my cable tv?
An electrician or an audio visual tech could measure the voltage on the coax cable that connects to the input of the cable box. The AV tech could also investigate the ground loop problem. If there is a difference in voltage between the ground for the AVR and the ground for the cable box, it might damage the HDMI input of the AVR.

I am not familiar with the cable systems in your country, but I find it hard to believe there is voltage on the coax coming to the cable box; there should only be RF signals. If there is voltage, a DC block would stop it. Even if there was voltage on the coax, the cable box HDMI output for the AVR should be isolated from that voltage.

When cable boxes in US first had HDMI outputs, some of them were not properly designed, and they damaged the TV HDMI inputs. I can tell that you want the best equipment available, but cable companies want to buy the least expensive box for their customers that will do the job. It is possible that the box has a poor design for HDMI output.

https://www.google.com/search?q=cab...UhwVQKHeYQBZ8QBQgkKAA&biw=911&bih=345&dpr=1.5

The concept of combining the audio and HD video in one cable is a good one, but the basis for HDMI was HDCP. The focus for the development of HDMI was on copy protection; little thought was given to the reliability of HDMI connections. The component connection is much more reliable, but HDMI is now more common.
http://whatis.techtarget.com/definition/HDMI

HDMI is definitely not a robust trouble-free interface.
https://www.google.com/search?biw=9...d=0ahUKEwiA5auIlJrZAhVKXKwKHWb6B_oQ1QIIkAEoBg

What model is your cable box?
 

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Discussion Starter · #7 ·
Hello, Morton; welcome to our Forum.
That is a very large power conditioner; you must have a lot of equipment connected to it. I would have expected you to be using a smaller model.

http://www.furmanpower.com/product/30a-voltage-regulator-power-conditioner-P-6900 AR E

datasheet
http://resources.corebrands.com/products/P-6900-AR-E/pdf_P-6900-AR-E_datasheet.pdf

manual
http://resources.corebrands.com/products/P-6900-AR-E/pdf_P-6900-AR-E_manual.pdf

https://www.amazon.com/Furman-P-6900-AR-Regulator-Conditioner/dp/B00ZAEQL1S

An electrician or an audio visual tech could measure the voltage on the coax cable that connects to the input of the cable box. The AV tech could also investigate the ground loop problem. If there is a difference in voltage between the ground for the AVR and the ground for the cable box, it might damage the HDMI input of the AVR.

I am not familiar with the cable systems in your country, but I find it hard to believe there is voltage on the coax coming to the cable box; there should only be RF signals. If there is voltage, a DC block would stop it. Even if there was voltage on the coax, the cable box HDMI output for the AVR should be isolated from that voltage.

When cable boxes in US first had HDMI outputs, some of them were not properly designed, and they damaged the TV HDMI inputs. I can tell that you want the best equipment available, but cable companies want to buy the least expensive box for their customers that will do the job. It is possible that the box has a poor design for HDMI output.

https://www.google.com/search?q=cab...UhwVQKHeYQBZ8QBQgkKAA&biw=911&bih=345&dpr=1.5

The concept of combining the audio and HD video in one cable is a good one, but the basis for HDMI was HDCP. The focus for the development of HDMI was on copy protection; little thought was given to the reliability of HDMI connections. The component connection is much more reliable, but HDMI is now more common.
http://whatis.techtarget.com/definition/HDMI

HDMI is definitely not a robust trouble-free interface.
https://www.google.com/search?biw=9...d=0ahUKEwiA5auIlJrZAhVKXKwKHWb6B_oQ1QIIkAEoBg

What model is your cable box?
Hello Rabbit73

Thank you for your advice.

I know the P-6900 might be a little overkill, but I wanted to make sure that there was absolutely no way that the amplifiers (NAD M27 x 2) and subwoofers (Genelec 7071) in my system would ever go power hungry or soft compress. As I had to install new power for my rack that moved location, I might as well pull a dedicated 30A wire and establish a connector for the P6900. The difference in price was not big. You might as well go big, right? ;-)

The CableTV box is a Panasonic DMR-BCT84. I had it tested, but the repair shop could not find anything wrong with it. It has been connected to the system for months, but WITHOUT the antenna signal on it.

I will get hold of a professional with the right gear to ensure that all is good with the antenna signal.

Another question:

The only components that are not under the Power conditioners "control", is the Cable signal and Ethernet entering the rack. The rack has its own ethernet switch that is powered from the Power Conditioner, but a cable enters from the router, that is not connected to the Power Conditioner. Does that have anything to say or should all devices connected to the LAN also be powered from the Power Conditioner to avoid any problems?
 

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You are being prudent to NOT connect Cable Coax to your Panasonic DMR-BCT84 BD-Player [with DVB-C Cable Tuner] until someone can check for damaging AC/DC Voltages [should be no more than a few volts] between Coax Shield or Center Wire and Chassis/Safety Ground on Panasonic AND other equipment....OR install an aforementioned CATV Isolator, which BLOCKS DC and Low Freq AC.

FYI: Info re Panasonic for those of us who Do & Don't understand.....uhh Finnish & Swedish [???]:
https://www.panasonic.com/fi/consum...-recorders/blu-ray-recorders/dmr-bct84en.html [I couldn't copy/paste to Google Translate]
https://www.larsbengtsson.se/produkter/visa/bild/bluray-dvd/bluray-med-hdd/panasonic-dmr-bct84 [CAN copy/paste to Google Translate]

PS: I've picked up a few words in German, such as "Fahrvergnügen"....which is the feeling I get driving my "new" 2006 Volvo V70 "R" 300-hp Turbo Wagon (67K-mi)....which was actually made in Belgium rather than Sweden, same as my (now wife's) 1998 V70 GLT "small" 200-hp turbo (100K-mi).....but other than THAT, I am totally lost trying to understand Swedish....or Finnish.
 

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I will get hold of a professional with the right gear to ensure that all is good with the antenna signal.
I would expect the cable TV signals into the Panasonic DMR-BCT84 to be about 60 to 70 dBµV:


75 ohm 0 dBmV

= -48.8 dBm
= 1.31825673856E-5 mW
= 60 dBµV
= 0.994330203663 mV(rms)

75 ohm 10 dBmV

= -38.8 dBm
= 0.000131825673856 mW
= 70 dBµV
= 3.14434818988 mV(rms)

Power Unit Converter
http://www.soontai.com/cal_exunit.html?Submit=Continue

You have cable TV signals AND antenna TV signals?

Since you have burned out the HDMI inputs of the Marantz 8802A AVR, you might try an HDMI to component adapter or converter to connect from the Panasonic HDMI output to the Marantz component input.

Both units have an LAN connection; would that work?
 

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