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Discussion Starter · #1 ·
My Toshiba DST-3000 is causing problems with my phone line. When the phone line is plugged into the DST-3000, I'm getting a radio station bleeding into the phone signal. Unfortunately this is not occurring 100% of the time, so debugging the problem has been difficult.


The amount of noise is enough that instead of connecting to the internet at 50K (which I usually do then the DST-3000 is disconnected), I can only connect at 19K with it plugged it.


I can't say for sure that the DST-3000 is introducing the noise (I think it is), but it is DEFINITELY amplifying the noise. Does anyone else have this problem? Does anyone have any suggestions?
 

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I haven't experienced that problem with my DST-3000. Inexpensive connection blocks capable of filtering RF interference are readily available. Check with any store that sells telephone connection equipment and accessories.
 

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Discussion Starter · #3 ·
Thanks for the replies guys. I have already disconnected everything that is plugged into a phone jack on the house, and then plugged a phone in at the box on the outside of the house (Mike, I guess that this is what you are referring to as the protector). Each time that I have done this, the line has been completely quiet, so I have assumed that the line is OK.


How would I be able to check that the protector is properly grounded? Is this something that I can do, or do I need the phone company to do something?
 

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Hi Bill


Most times radio noise on a phone line is caused by an unbalanced cable pair (one side off the pair is longer than the other. If you can disconnect everything at the protector (on the outside wall of the house) and go to a neighbors and have the phone line tested by the phone company. If the line is unbalanced they will cut you to a new cable pair and the problem should resolved. If the line tests okay I would make sure the protector is properly grounded. I am pretty sure you are right that the DST-3000 is amplifying an existing problem. If you are located close to a radio station's transmitter the phone company can provide you with filters that can be placed either at the Protector or jack.


Good Luck Mike
 

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Hi Bill.


At the protector (box) you should find a number 10 ground wire running to a nearby cold water pipe or ground bar. If you have an ohm meter make sure you have continuity from the ground source to the protector. If want to get more involved with the wiring remove the drop wire that comes from the pole or is buried. Put your ohm meter across the protector lugs that still have the inside wire (IW) attached. You should see zero ohms. Then put one side of the ohm meter to ground and test tip and ring ( each side of the inside wire). Again the results should be zero ohms. If the reading is not zero unplug your phones and other equipment one at a time. If it goes to zero you probably found the source of the problem. Now you hook everything up the way you found it. I once ran into a situation where the radio was caused by a fax machine. It had a built in phone and if you unplugged the machine from the jack and listened to the phone you heard the radio station. Good luck and work slowly and safely. Gee I thought this was supposed to about HDTV , not telephones.
 

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Bill,

I was wondering if you found a solution to this problem. I haven't heard any radio noise but I have similar symptoms. Anytime my DST-3000 is plugged in, my modem is unable to connect at the usual speed (around 48K). It's only a mildly annoying problem but I'd love it if there's a cheap solution.


Barclay
 

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Discussion Starter · #7 ·
Barclay,

No, I haven't been able to fix this problem (other than unplugging the box whenever I use the Internet). I have reported this problem to Toshiba, and they said that they have no other reports of this problem. They have passed the problem on to management, and are supposed to get back to me.


PLEASE report your problem to Toshiba. The number is (800)631-3811 (if you call the number in the owners manual, a message will tell you to call a second number for Satellite Dish boxes, if you call that number, they will tell you to call this number for HD satellite boxes).


The person that I spoke to was named Joy, if possible speak to her to report the problem. Mention that it's the same problem that I had so that she can get both of our complaints linked together.


Bill
 

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I was wondering if you were using a wireless phone jack for the HD box. I have seen these introduce radio into the phone lines.


Ira


------------------

Ira Solod [email protected]

Pioneer Elite 510, Lexicon DC-1 ver.4 DTS, Parasound 1205A 200W x [email protected] ohms, M&K S150THX LCR, M&K Surround-55 rears, Klipsch PSW-10 sub, Pioneer DV-F727, Quadscan Pro, DTC-100, JVC 7600 SVHS, Camelot Dragon 5.1, Power Wedge Ultra 111, Monster Power 2500, All homemade interconnects made mostly from RG-6QS
 

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Discussion Starter · #9 ·
No, I am not using a wireless jack. I had considered that cordless phones on the same line could be causing the problem. But I also ruled that out.


I tested to the point that I had the receiver plugged into the jack at the outside of the house (the telephone interface box) and a single line connected to a standard (corded, no answering maching, no electric plug) phone, and nothing else connected and no splices in the line.


If I picked up the phone and pressed a button (to eliminate the dial tone), noise was present when the receiver was plugged in, and there was dead silence when it was not.
 

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I think you've proved the receiver is bad with your last experiment (a very good one, I might add). It is possible that a lighning hit (not necessarily a direct one) has caused the Subscriber Line Interface inside your box to go into trouble. It sounds like one side is grounded.


I disagree with the "0 Ohm test" mentioned earliers. You should have an infinite impedance between each side of the line and ground, not 0 ohms. I'll bet if you measure each side of the wire to the F connector of the receiver you will find a finite resistance on one of the connectors. This is usually the blue/blue white wire, you can take an old RJ-11 cord, cut it in half and measure each of the wires to ground. NONE of the wires should show any conductance to the F connector, if it does, that is the problem. When the line becomes unbalanced, everything comes apart. The long antenna lead running to the satellite receiver becomes a long wire antenna for AM radio. If this is connected (via the shorted component) to the phone line, non-linear elements in the phone line (cheap phones, etc.) "detect" the AM broadcast signals and convert them to the audio you hear on the line.


The experiment you did taking the receiver outside has narrowed it down to the receiver. Looks like you're going to have to have it serviced.


Bob Smith
 

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Well then, they've blown it. Make sure it has an FCC ID number for the telephone port. There's a little blue book, I think it is Part97 that describes equipment balance, resistance, and the other parameters of equipment connected to the publically switched network. It is hard to believe Sony would not conform to this, but if so, you need to get them sensitive to it.


Bob Smith
 

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The DTC-100 has a relay inside that completely disconnects the phone line from the modem until it is interrogated by the satellite down link. Maybe Sony used some kind of solid state switch that goes non-linear in the presense of strong AM stations close to the receiver. Most consumer electronics is supposed to work in the presence of RF fields of about 2V/Meter, maybe Sony didn't check this on the new unit. You should give them a call.


Bob Smith
 

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Discussion Starter · #13 ·
Charles,

Please contact Toshiba about your problem. I have provided the necessary information in an above post. I think that it would be a good idea if you tried to speak to the same person that I spoke with, so that she can link the reported problems together. They will ask you for the date of purchase and the serial number of your receiver.


Bob,

Thanks for your input. Just one correction, this is a problem with the Toshiba STB (not the Sony)
 

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Toshiba! Sorry, I get these things mixed up from time to time. Something else you might try (though It's pretty iffy). Try using a shielded RJ11 cable between the phone jack and the DSS receiver. Not sure where you're going to get one of these, we used to make them for Ethernet stuff. Ground the shield end to some metal on the receiver. This will form a "capacitive divider", the capacitance of the shielded cable will shunt some of the signal to ground. This may be enough to lower the signal to a point below that needed for rectification in the phone interface and might help. Chokes on the cable probably won't do much, they become effective at higher frequencies (50 Mhz and above), so they won't do much for broadcast band interference ( MHz or so).


Another thing to try, only 2 wires (one pair) is used for telephone signalling, try grounding the unused wires to the chassis. This might have the same effect as the ground braid and help shunt some RF to ground.


Bob Smith
 

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Just wanted to let you know there're others. I have the same exact problem. Radio music over the line, decreased modem speed, which all goes away when I unplug the DST3000.
 

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Bill,


Thought about it last night and figured out that if you did use one of those power line phone extender combinations, the problem might just go away. The problem is the long phone line into the Toshiba receiver. By using only enough line to get to one of the power line adapters, the amount of RF picked up by the receiver will be reduced. I haven't heard of any complaints about the extenders causing the problems you talk about, so it might be OK. In any event, it is disconnected from the phone line except for the short time when it is in use (during an upload from your receiver). Maybe you could borrow one from Radio Shark and if it doesn't work, take it back.


Bob Smith
 

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Discussion Starter · #17 ·
Radio Shack has a very good return policy. I already bought and returned the RF-Filter (that was suggested in an above post) from Radio Shack. I'll give this a try. Thanks,

Bill
 

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I'm a little late in this conversation, but did you check to see that you have the proper polarity with your telephone line? Over the years, I have seen modems act very strangely, and sometimes not at all, or worse, fry them without the proper telephone line polarity.


I believe Radio shack has a tester, but I'm not sure if it is any good. I use an IBM Modem Saver, that was about $30 when I bought it about 5 years ago. It works very well, and has saved my installations many times.
 

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Discussion Starter · #19 ·
Bob,

Your idea worked great (I'm currently connected at 50K with the receiver plugged in). I'm still hoping that Toshiba will replace this box with one the works correctly. But this is a great interm solution.


To anyone else having this problem, who wants to go the same route. The wireless phone jack is $20 cheaper at Home Depot ($49) than at Radio Shack ($69).


Thanks for the great advise Bob.
 

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This has been my first chance to check out the boards in a while and just wanted to mention that I did call Toshiba and could hear the blank stare over the phone. They took my name and said they would check on it's been a week and I haven't heard a thing - not really surprising. I would rather not buy a phone line extender since the unit is right next to the line, but it makes sense that might solve the problem.


Barclay
 
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