Technical and Repair Assistance

Started by b3b0palula, September 10, 2006, 01:08:43 am

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Ruthenium

Found the problem: b0rked drive belt.
Thank goodness the seller provided a new one!

superpope

Why don't I get answers?  Are my questions too hard?  ;)

Ruthenium

I don't mean to be disrespectful to your questions, superpope, but it seems that I have another problem.
I replaced the drive belt in the FDS, and it started working a few times.
But then, I found that the video started turning grey, and was very staticy. I checked the connections, and they were fine. Now, I'm getting no video at all, but the audio works.
I did not open up the Famicom, and I did nothing that could've messed up the internal parts.
I'm really hoping that I didn't somehow mess up the A/V mod.

ericj


133MHz

Quote from: superpope on October 21, 2009, 01:46:31 pm
Why don't I get answers?  Are my questions too hard?  ;)


Yes, they are. :P
I couldn't give you an exact answer without poking my multimeter around your Twin, and I'd probably need an oscilloscope too.
Well now you know that the problem is in the RAM Adapter portion of the Twin itself, which includes the 2C33 chip and everything in its path until it reaches the drive mech. connector. You'd have to follow the /WRITE GATE and /WRITE DATA signal all the way from the 2C33's pins to see if there's something breaking its path along the way. Failing that, replace the 2C33.

Quote from: Ruthenium on October 21, 2009, 02:14:38 pm
I don't mean to be disrespectful to your questions, superpope, but it seems that I have another problem.
I replaced the drive belt in the FDS, and it started working a few times.
But then, I found that the video started turning grey, and was very staticy. I checked the connections, and they were fine. Now, I'm getting no video at all, but the audio works.
I did not open up the Famicom, and I did nothing that could've messed up the internal parts.
I'm really hoping that I didn't somehow mess up the A/V mod.


It seems that you did mess up the AV mod... :-\
Standard troubleshooting techniques apply. Try poking around with the tip of the Video RCA connector around the video connections and see if you can get a picture.

ericj

The video turning gray and staticy would probably be a problem with the RAM, RAM connection to Famicom, or FDS. Try a cart game and see if the video works.

@superpope: try adjusting motor speed first. Only adjust the head as a last resort and be careful not to strip the screw in it if you do.

133MHz

Quote from: ericj on October 21, 2009, 02:27:57 pm
The video turning gray and staticy would probably be a problem with the RAM or FDS.


Why would this happen? Increased power consumption of the FDS RAM Adapter vs. common cartridge?

Ruthenium

October 21, 2009, 02:33:46 pm #1027 Last Edit: October 22, 2009, 08:29:36 am by Ruthenium
nope, it's happening for the cart games as well.
Jeez, if this thing is causing me this much trouble, I might as well go find a cheap game genie and sell the famicom.

Alright, against Ericj's wishes, I decided to open up the famicom. I loosened up the AV mod parts, and now it works like a charm. :D

superpope

Quote from: ericj on October 21, 2009, 02:27:57 pm
@superpope: try adjusting motor speed first. Only adjust the head as a last resort and be careful not to strip the screw in it if you do.


Thanks!  I'll give it a shot.

ericj

October 22, 2009, 07:37:53 pm #1029 Last Edit: October 23, 2009, 08:29:03 am by ericj
Quote from: Ruthenium on October 21, 2009, 02:33:46 pm
Alright, against Ericj's wishes, I decided to open up the famicom. I loosened up the AV mod parts, and now it works like a charm. :D


Glad it's working for you again. I'd suggest just pulling the carts out and not moving the eject lever to do it since it may (although unlikely) catch on a wire and cause you problems. And my suggestion was before when it was working not to open it. Since it wasn't working right, opening it to take a look makes sense.

So, I have a FDS question, too. I got a writable drive from madman that needed a new belt & a RAM adapter. I got both in the mail and put the new belt on today. It reads about every other disk I have okay. So, I'm thinking I may need to adjust the motor speed. But before I do so, he said the motor speed was adjusted/optimized with copymaster. From what I understand, that adjusts the drive speed to write & read disks faster. Would it be stupid for me to adjust the motor speed? Should I be looking at something else first? I did clean the head with a cleaning disk and that helped somewhat. 

133MHz

Maybe it needs its speed adjusted again, since the tension exerted by the belt can vary it. Also did you align the spindle after replacing the belt?

superpope

On my issue: I adjusted the motor speed yesterday evening.  Tried then entire range in microscopic increments and never got any message on-screen except for Err. 22 and the occasional Err. 21.  I tried matching the speed of the drive by comparing its "tone" to the sound of my other FDS drive that works perfectly.  Still no luck.

I'm a little confused by the concept of spindle alignment...I did the belt replacement by following a video on YouTube that suggested I mark the indentation with a sharpie and replacing it without ever removing the black plastic cover.  That is what I did.  I fidgeted with that quite a while, thinking my problem was that I was doing that wrong, but since everything I try is just a stab in the dark I just tried to align it as best I could and went on.

So is the dreaded head alignment my only resort at this point?

ericj

Quote from: 133MHz on October 23, 2009, 10:01:29 am
Maybe it needs its speed adjusted again, since the tension exerted by the belt can vary it. Also did you align the spindle after replacing the belt?


I did align the spindle and am pretty sure I got the screw perfectly in that little indentation. I'll recheck it, and, if it still has the problem, I'll try adjusting the speed. Thanks  :)

Quote from: superpope on October 23, 2009, 11:01:44 am
So is the dreaded head alignment my only resort at this point?


Did you clean the head?  If not, try that and make sure all the switches are in the right places and that none of the wires broke off at the solder points. If all's good, you'll probably have to adjust the head.

Nightstar699

I have a famiclone that looks like a real fami. It turns on. On the back, there is a white and yellow labeled video audio. And a red labeled Rf out. I tried with a nes rf. I tried avs, but it acts like nothings in there! Please help me
So ends another chapter in the glorious legend of the Ninja... Until next time...

133MHz

A NES RF Switch won't work with it - those Famiclones need a manual RF switchbox (not enough signal strength to trigger automatic ones).

Try the AV leads in all sorts of combinations. It's not rare for them to be mislabeled or something.