Project Dreamcast - Repair part 2

Last time I talked about the repair efforts on the Dreamcast GD-ROM drive.  The new laser will read CDs, but will not read game discs.  As I said, I don't know if the trimmer needs adjusting or not.  But before I go that route, I wanted to check the rest of the GD-ROM drive.

Removing the entire GD-ROM drive assembly reveals the circuit board for the GD-ROM drive.  The GD-ROM circuit board has a total of 10 surface mount electrolytic capacitors on it.

Capacitors are frequently the cause of old electronics going bad.  Is it possible these old caps are preventing the GD-ROM drive from reading discs?  I just so happen to have an ESR meter which is the best way to test a capacitor to see if it's good or bad.

When testing ESR values, lower is better.  A high ESR value means the cap is going bad.  Here is a table of the capacitors, their rating, the current ESR, and the expected ESR value.

As you can see, every single capacitor has a higher than expected ESR value.  So before I try adjusting the trimmer on the laser, I want to replace these capacitors with new ones and see if that helps.  Unfortunately I don't have any surface mount capacitors in my parts box, so I'll need to order new caps.  I'll continue repair efforts in my next post once the replacement parts arrive.

The last thing I'll mention is the manufacture of the GD-ROM drive.  The initial manufacture of the GD-ROM drives was Yamaha, but later on Sega switched to Samsung.  From what I've heard, the Yamaha drives are much more reliable.  From other repair work I've done, I've run into a lot of bad capacitors on Samsung products, so I won't be surprised in the least if the capacitors are the problem with this drive.

Sci-Fi Review - Star Trek

As a self-proclaimed "nerd" I realize there is one thing missing from my blog - my personal views and opinions on classic Science-Fiction.  In this first installment in a series of posts I'll talk about Star Trek... the original Star Trek from the 1960s.

I'll start off by saying I LOVE Star Trek!  Star Trek is easily my favorite Sci-Fi program, beating out other heavy-weights such as Star Wars and Stargate.  As a kid I loved the space scenes, the futuristic nature of the show, the special effects, etc.  But as I've grown up with Star Trek, I've come to realize what makes Star Trek truly great isn't this "technical" aspect of the show but it's the character development and Gene Roddenberry's depiction of the future.  I guess you could call Gene the ultimate optimist.  His view of humanity's future was extremely positive.  In Star Trek he depicts a future with very little crime, disease, or pollution - one in which all mankind has learned to get along with everyone else, and in which the "goal" that drives people forward isn't the acquisition of wealth, power, or money but the driving force is betterment of mankind as a whole and increased knowledge and understanding.  That in and of itself is very radical thinking.  It creates this positive world in which you, the viewer, find yourself wanting to be a part of.  To see a future where you don't have to worry about food, money, or illness and can instead focus on learning and helping others is very captivating.  That's kind of the background of Star Trek in general.  But let's talk specifically about the Star Trek from the 1960s.

Even though I LOVE Star Trek, I just cannot watch the original Star Trek.  The problem has always been the low production value, I have a hard time getting past things like blocks of foam painted to look like rocks.  Having been born in the mid 70s, I grew up in a world post Star Wars.  This set a new standard for special effects in Sci-Fi.  So when I try and watch the original Star Trek, I have a hard time.  As such I've only seen a few episodes end to end.  And yes, it's hard to judge an entire show based upon one or two episodes.  I really should go back and sit down and watch the episodes.

Even though I haven't seen much of the original Star Trek, I have seen enough to know what I like and don't like.  Starting at the top, I never cared for Kirk.  He's portrayed as a "ladies man" which to me isn't what Sci-Fi is about.  I don't watch Sci-Fi to watch someone "hit" on every sexy alien they find.  Spock on the other hand, I always liked his cold hard logical aspect.  Beyond the big two - I liked Scotty the engineer, although I felt his accent was a bit thick.  Many of the other characters had less of an impression on me.  I liked that Gene included different nationalities, races, and sexes in his future.  Although the true impact of this is probably lost on me having grown up after the race and general equality movements of the 60s and 70s.

As for the technology of the show - some of the futuristic ideas have already become reality.  If you compare the Star Trek communicator to a modern cell phone (in size, design, and function) you'll find they are nearly identical.  We obviously don't have large star ships and faster than light space travel, but I would argue modern super computers probably exceed what is depicted in the show.

I guess to sum up, although the original Star Trek series isn't for me, it did lay the necessary groundwork for the future Star Trek series.

Project Dreamcast - Repair

As I said in my previous post, the Dreamcast I bought on eBay was listed as "broken."  When I got the unit I plugged it in and turned it on.  The system powers on and the welcome screen comes up.  The controllers work as does the VMU.  But the system will not read any discs; neither Dreamcast games nor music CDs.  This is actually a very common problem with the Dreamcast - in fact it's probably the single biggest problem that happens to Dreamcasts.  The lasers they used in the system tend to wear out quicker than other CD players and games systems.

Step one is always clean the laser lens.  Very carefully use a Q-tip and rubbing alcohol to wipe the lens.  You can also use compressed air as there is a second lens further down that you can't reach.  Neither of these worked for me, so I moved onto the common "fix" found on the Internet.  Every CD/DVD laser assembly has a trimmer that adjusts the power of the laser lens.  Note, a lot of people call this a potentiometer, but the technical name is a trimmer, or sometimes a trimmer potentiometer, or even a trimpot.  Here is a picture of the Dreamcast laser trimmer.

If you turn this trimmer clockwise you increase the power to the laser, counterclockwise to decrease the power.  The idea is to increase the power to the laser just to the point where it reads discs.  Increased power reduces the life of the laser, so this is at best a short-term fix.  Some people report that counterclockwise worked for them, but this doesn't make any sense.  Either way, you SLOWLY turn the trimmer clockwise and retest.  This is a long slow process of increasing the trimmer, testing, increasing again, etc.

Following this process I got it to read music CDs every time.  But game discs are another matter.  I got it to periodically read game discs, but most of the time it failed.  After several hours trying different settings, I decided to punt and try installing a new laser.  I purchased a JVC SPU-3200 laser assembly.  This is a functional replacement part for the Dreamcast.  Here's a picture of the new laser.

Replacing the laser was surprisingly easy.  There is one important task to remember when installing a new laser.  To protect the laser against static electricity, there should be a solder ball on the bottom of the laser.  You need to use a soldering iron to remove this solder ball.  After doing this you can reassemble the Dreamcast and test your new laser.

With the new laser installed, I tried a music CD.  It read the disc perfectly - this is good, I know the new lens is working.  However, it still won't read game discs.  At this point I'm not panicked.  I honestly don't know if new laser assemblies ship calibrated or not, so all I might need to do is calibrate the laser.  However, before I touch the trimmer on this new laser, I want to look at the rest of the GD-ROM drive circuitry.  What if there is another problem that is preventing it from reading game discs?  Next time I'll cover the continued effort to repair the Dreamcast.

Project Dreamcast

After the success of Project Genesis and Project TG-16, I have my next project to work on - a Sega Dreamcast.  I've never played a Dreamcast before - in fact I know very little about the system.  What I do know is the console was probably one of the most underrated and overlooked video game consoles of all time.  It was ahead of its time in many ways.  The Dreamcast was the first console to offer built-in network and Internet connectivity, it was the first to offer progressive video output, the first 128-bit system, I believe it was the first to offer a keyboard and mouse, and it had a lot of unique titles not found on any other console.  Add to that it was about half the price of competing systems.  Unfortunately the console was short-lived.

I recently picked up a Dreamcast off eBay.  I got the console, two controllers, a VMU, Unreal Tournament, and power and video cables all for $20 delivered.  The reason the console was so cheap is because it's "broken."  It may sound odd, but I'd actually rather get a broken Dreamcast than a working one.  Why you might ask?  Well fixing a console is as much fun as playing it in my opinion.  And after fixing it up I'm going to mod the console to improve it and make it special and unique.  I'll document the entire process here.  Unlike Project Genesis and TG-16, I'm going to document this as I go.  Both of those projects I completed them before making a single post.  But this one I'll post as I go, which hopefully will help others to see how I go about trying to diagnose, repair, and mod the console.

Before I talk about the repair efforts, I wanted to give my impressions of the console.  First, I am surprised by the size of the console.  It's a very small console.  Secondly, the controllers feel nicer than I was expecting.  I especially like the analog thumbstick.  It's been my opinion that most analog thumbsticks are stiff and/or move in a clunky manor.  But the Dreamcasts thumbsticks are (pardon the expression) a dream!

Next time I'll get into the repair efforts on the console.