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TSN_Tom
12-30-2003, 12:29 AM
I have read and searched but I'm not seeing the answer to this problem.

I have just received a Series 1 Hughes Tivo Gxcebot and when I first checked it, it had no signal on any of the transponders except 1&2 where I have good signal.
I have an 18" dish and two lineís down from it. I had a IRD on it before and all was fine. But when I checked it with this Tivo no signal.
I have setup a series 2 HDVR and it works fine on that line.
I have tested the two inputs but both are the same only signal on 1&2. I have changed the zip code and area code to match (No dif.) I have tested the voltage output from the tuners and get 13.4 and 18.5 on the odd and even.
I donít know what else to try. I have changed software on the drive several times and am now on the Xupgrade 2.5.2. Also note when I tried the Sony image, the remote no longer worked so I went to the T60. This worked but no signal.
This is not my system but said I would look at it for a friend and as a good friend I'm exhausting all my resources.
If anyone has some helpful advice, pleases help to point me in the right direction.
Note: This system can't be sent back for warranty. It's either fixed or scraped. Anyone need a good power supply I think it's good.

Thanx

captain_video
12-30-2003, 10:41 AM
The 13.4 and 18.5 volts you're measuring are the switching voltages for the LNBs and have no bearing on whether the tuners are actually working. Look in the experts forum and you'll find a schematic for a Sony SAT-T60. The mainboard and power supply are identical to the GXCEBOT. Check for the 30 volts from the power supply to the tuner modules. If this is absent or low then the power supply could be your problem. I believe there are threads in the experts forum that discuss tuner problems. You might also check with GREEK as he seems to be one of our resident hardware gurus.

TSN_Tom
12-30-2003, 08:24 PM
I had a Look and found the Dwg's,
Now what I did is checked the DC Voltage form the ribon from the PS to the board and there is 10 conducters some have voltes but none had 30 volts is this where I am to check.
Thanks
Hay by the way did any of you sell you old junkers on Ebay.
Just Kidden.

GREEK
12-31-2003, 04:24 AM
Just pop a voltmeter on C256 or C259 and you will have 3 volts I bet. You should have 30. You can locate these two as the third and fourth down from the top on that block by the ribbon connector. To the left of it is the small white #s I reference. Basically, you either need time to test and the experience working with advanced tools and electronics to find it quickly, or start taking off a cap at a time til it comes up and you have your culprit. I wouldnt even attempt it without tools unless I had a serious jones for stress 101. The only good part is this can be fixed for nothing usually, just a few pennys for a new cap or a borrowed one for free..........

TSN_Tom
01-01-2004, 03:10 PM
OK I have had a look and your right I don't have the 30V you spoke of.
When I went across all the C# I could only get Volt's on one side, that is the side closes to the power supply, this is what I got.

c249 24v
c255 24v
c256 1.5v
c259 1.5v
c264 5v
c271 5v
c279 11.9v
c287 11.9v

Now you had mentioned swapping out the cap's on the Board is this on the main board or on the Power supply?
If I can get the parts locally I will just swap them all out and test after each one to see which one fixes it.
Any advice would be helpful.
Thanks and Happy New Year

GREEK
01-02-2004, 02:38 AM
This is a pretty nerve wrecking job if you know not what your doing Basically, one of the caps on the line is bad. Not visibly usually, just functional wise, and is hanging the line down by shorting it out. It is normal to have voltage only to one side, thats how electronics work. You either need the proper equipment to pinpoint the problem, or the deadmans way is to remove every cap one by one to find the bad one. THeres no need to replace every one, only 1 will be bad. When the line frees up you found the problem. DONT run a tivo without all caps in place and proper kind as well. You also need to remove one of the tuners to get in the 30 volt line to tuner#1, this is not an easy fix at all for 99% of the people out there, but if you got the time and patience, go for it. You need the schematics to figure out whats on that line......

TSN_Tom
01-02-2004, 03:40 PM
Thanks for the Help
I have the time and patience to get this going but is there a way to tell if the problem is with the power supply or on the Main board.
IE Check the output on the ribbon cable from the PS to the board and that would tell me if I have the proper output from the PS.

I have the schematics from the Experts form but it looks like it's just of the PS is there one for the Main board or is this part two up Mission Impossible.
Lastly I thought that the Caps that you were referring to were the round brown silo like things, I have the ability just not all the knowledge.
Thanx again.

GREEK
01-02-2004, 06:48 PM
you got alot of reading to do realisticly. The silo looking things are other parts, were talking about match head whitish looking bits that are rectangular, about 2000 of them on the baord, and about 20 on the 30 volt line itself. The cap (capacitor) is a small ceramic "bit" that is soldered to the board to clean voltages. If you eventually find the bad one, it can be replaced with a ratshack equivilent that is encased in orange plastic, as long as the #s are right and its ceramic internals. The supply CANNOT ouput power if it is being held down by a ground, it DOES NOT matter what the supply does, its not your problem here, the actual 30 volt line, all the way from the supply connector to the tuenrs has a short somewhere. As a hint, your starting on the wrong side of things, trust me. You have the wrong schematics, its in 5 parts, you need winrar to view it, and its under a post by 1dave1 about power supplies, T60 schematics is what you need, they are ALL the same units internally. If you are not a good solderer, your gonna make a mess. TO get to the caps in the crevice of tuner 1 and 2, you need to remove one of them, this requires some sort of desolder technique, and tools. Maybe some reading about electronics would help. In the end, just the tools you'll need to buy if you dont have will cost more than the repair would, not to mention the headaches and aggravation. A decent repair shop should be able to do this with the schematics in hand in about 30 minutes if they have a clue to electronics, someone who knows these units could do it in 5 minutes flat........

TSN_Tom
01-02-2004, 11:48 PM
Thanks for your help
I have it and have put it together.
Give me some time to look through it and I'll get back to ya latter This will help a lot.
If not for me it will for the service shop I take it to.
Thanks again and Ill let ya know how I make out.

TSN_Tom
01-04-2004, 10:59 PM
Onec again I would like to say thanks.
With out this form and its resources I wouldn't have been able to fix my Tivo's problem.
The problem was with one of the caps on the 30V line and I was finely able to get it to show it self to me.
I am now up and running.
If you have any questions I can be more specific about if it will help anyone else.
But for now I would just like to say thanks
The right DWG's really help.
TSN

GREEK
01-05-2004, 03:22 AM
unfortunately its a couple different caps that go bad, not just one. the schematics and some skill is all one needs really. BTW, its a bad idea for anyone to run thier unit for long with a missing cap on the 30v line, or anywhere else for that matter, especially the 30v though