Friday, September 26, 2008

How I learned to Solder (or DANG! That's hot!!!)

We depend on our Digital Video Recorder. Yes, we watch way too much TV, but I have a Radio and TV Journalism degree, so doesn't that give me some kind of special dispensation?

Anyway, our faithful Panasonic DMR-E85H (a DVR with a Hard Disk and TV Guide program guide) decided to show us the "Please Wait" message and nothing else. Turned it off and on. Searched the web. Called Panasonic and tried all the secret key combos to reset everything. No luck. We could ship it off to them and have a repair done for $130, but buying a new DVR with a digital tuner wasn't a whole lot more than that. So we bought a DVD recorder from Wal-Mart. The Panasonic was relegated to sitting on the fireplace unplugged for a few days.

But I got around to doing a little more research on the web, to see if maybe I missed something. And I ran across a post about someone having the same problem and fixing it by replacing a couple of capacitors that had gone bad. Hmmmm.... could this be our problem too?

After reading the post and a couple of related posts referenced, I cleared off the dining room table and opened up the unit. After fumbling around figuring out which screws to take out , I finally got down to the power supply board. Yup, the two capacitors in question had bulging tops and a little leakage. So now it was off to Radio Shack to buy a soldering iron and a couple of capacitors.

Now armed with my $7.99 Soldering kit (completed with a little metal stand, a double ended pick/scraper thingie, some clippie thing that is supposed to be a heat sink and a length of solder wound up like a spring), I set to removing the bad capacitors.

First I tried to "tin" the tip of the iron. This is supposed to coat the tip with metal to make things go on and off smoothly. Ok, melted some solder on the tip. Now to desolder the bad capacitors. According to what I read, you just used the hot iron on the back of the circuit board to melt off the existing solder. That should be easy. Well, then again - maybe not. First off, my hand is not as steady as I thought. I keep jabbing the circuit board as the tip slides off the solder point. Boy there is a lot of smoke. At the same time I am trying to wiggle the capacitor on the other side of the board loose. This is slow going..... And the heat from the iron makes the capacitors quite hot to the touch. In hindsight, maybe I should have read more on that heat sink thing. But finally I get one side loose. Hopefully I haven't scorched the board jabbing it with the iron tip. After a while I have both capacitors out of the circuit board. Sigh of relief.

Now its time to put the new ones in. After a Google search to see which lead is positive and which is negative (longer lead is positive), I position it in the correct holes in the motherboard. After I check to make sure there is enough room, I decide to leave them upright rather than laying them down on the board. I bend the leads enough so the capacitors don't go too far up or down and begin trying to solder. Strange, it seems like the solder is just vaporizing as I touch it to the tip. I don't get any little drops of solder to fall onto the lead to bond it to the circuit board. This turns into quite an ordeal before I finally get some solder to drip down where I want it. After struggling to get all 4 leads soldered, I have both done, put the board back in, put the hard drive back in and screw the case back on.

I take the unit over and put in on the brick fiireplace, carefully clearing all flammable items from the area. Well, something could go "Pop" you know? The moment of truth comes. I plug it in and ....... nothing. Not even a "Please Wait". Rats. Oh well, we still have the new recorder. Well, actually - we took that recorder back because it turned itself off a couple of times. We order a new one with a hard drive online. (Magnavox H2160MW9 - post from AV Science Forums - which is THE place to get info on all things TV and Audio. Great place to search for opinions on things you want to buy and help for stuff you have.)

Later, just before I fall asleep, I realize in my elation of actually getting solder to hold the capacitors to the board, I didn't trim the leads after I soldered them in. Maybe they are touching the case and causing a problem. So next day I unscrew the case, remove the hard drive, and remove the circuit board. I trim the leads and discover that one solder on each capacitor had come loose. Time to heat the iron up again. Trying again and again to heat the solder already on the leads proves difficult, and I worry I am charring the circuit board. I have to put more solder on and again, it seems like it just evaporates. Then I manage to drop a big glob of solder on the circuit board, but not where I need it - CRAP! I wait for it to cool and then keep tapping it with the iron, trying to get it to cling to the iron and come off the circuit board. I finally get that clean as best I can. I solder the leads and let them cool several times before I get them to stick. And of course, in my impatience, I am one point grab the soldering iron a bit too high up on the barrel and singe my fingers good. Hold them under cold running water then against an ice pack for a while.

Finally, everything seems to be holding. I screw everything back together again and walk over to the fireplace. My wife suggests the patio. I'm not surprised. I go out, plug it in, and ......"Please Waite". Cool! At least I'm back where I started. But wait, the screen changed. Can't read it in the sun. Wife comes out and I hold the unit up for her to read. Has the current time on it. Could it be?

Take the unit in, plug it all back up, and turn it on. The thing actually starts up! All the programs we recorded and haven't watched yet are still there! Those programs are immediately dubbed to DVD for safekeeping. We turn it to standby so the TV Guide listings can download. My wife walks out to the living room the next morning and the unit is recording the Today Show. It even remembered what we had set up to record. Amazing! Despite all the mishaps trying to solder, I actually repaired the unit for under $10 and some blistered skin. Many bonus points from the wife!

So now we have 2 DVD recorders with hard drives just in time for the new season. It remains to be seen what we will be able to do with the Panasonic when the digital switch comes as it is analog only. I read some post about a certain converter box and an IR Blaster. Hmmm...we'll see.

So the moral of the story boys and girls - you too can solder! Just watch where you grab the freakin' thing. And here are some of the posts that walked me through the process:

From,, and the first post I found that led me to fixing this, again from Many thanks to the people that posted those great instructions. My wife thanks you too!

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