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View Full Version : I replaced switching board on DSR6000, still problems



Rockstead
05-23-2003, 06:59 AM
I have two DSR600's and both had power supplies that died, I ordered SA power supplies as suggested in another thread and had a tech replace the switching boards on both.

It solved the problem 100% on one unit, and initially it appeared to solve it on another, but my for the second day in a row I've woken up to find my unit powered off. I still can hear the clicking noise and the fan cintinues to turn, and yesterday for whatever reason I re-inserted all the ribbon contacts and power cables and the unit turned on, but yet again this morning it is off again.


Does anyone have any suggestions on what I can try next? when the unit was working, both tuners worked pefectly. Although as I satted in a previous thread, for whatever reason this machine did not let me bash through the serial port.

I have plenty of left over SA power supply parts, does it make sense to try and replace any other parts from it? if so I have no idea what to try first.

any adivce would be appreciated, thank you.

captain_video
05-23-2003, 09:24 AM
I'd start by checking the output voltages of each of the regulator chips and see if you can find any of the voltages that aren't in tolerance. Check 1dave1's thread on the DTivo power supply schematic for help. If you don't fee comfortable with troubleshooting your power supply then you might consider one of the repair services recommended in the How Tos Only sticky thread in the main DTivo hacking forum. I believe the cost for repairing a power supply is about $90 plus shipping.

Rockstead
05-23-2003, 03:08 PM
Thanks for the feedback,

I checked that Power supply thread, I did not find specifc instructions on checking the output voltage on the regulator chips (not even sure which are the regulator chips). I want to provide my tech friend with all of the schematics and information he'll need to test and how to test and what to test, I'm just not sure how to present the information to him.

It was easy getting him to change the switching board, because I just provided him a new SA P/S and he just removed it and placed it on the power supply.


TIvo Repair mentioned that it could be possible that U37 or U38 could be failing, I know those are located on the motherboard, can those be easily changed? I would like have the power supply trouble shooted before exploring other options..if that makes any sense.

captain_video
05-27-2003, 08:51 AM
The regulator chips are the ones with the rectangular packaging mounted on the heatsinks. They will usually have three pins (input, ground, and output). Check the voltages on the input and output pins with respect to ground. You'll have to look up the spec sheet on each one to see which pins are which. I'm pretty sure they'll be the same for all of them but I can't remember which pin is which off the top of my head.

Rockstead
05-30-2003, 08:15 AM
Ok I haven't had anyone check the volatges dsr6000 yet, but these are some of the sysmptoms.

Like I said I've already replaced the switching board from a SA P/S and it worked for a few days.

Now whenever it stops working, I disconnect the hard drive and power supply cables, I push down on all the Power Supply parts (may sound stupid). What's strange is that sometimes this works, I don't know what I do, but it will then boot up and my Dsr6000 will then work anywhere from 12 hours to 4 days, but usually no more than 12 hours.

Just wanted to share thsi info incase it points to what could be causing hthis problem.

Thank you.

captain_video
05-30-2003, 08:34 AM
If you can get the power supply to work by pushing down on all the parts then it sounds like a bad solder joint somewhere or perhaps a broken component lead making intermittent contact. I'd pull the power supply and inspect all solder joints with a magnifying glass to make sure there aren't any cracks or cold solder joints. I'd start with the connections at the switching board since that's the last place you worked on it.