Technical and Repair Assistance

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

Previous topic - Next topic

Lorfarius

Id have to buy/import another adaptor to test that out. Was hoping there was something else I could do.
My own Retro gaming YouTube channel: http://www.youtube.com/user/Lorfarius

ericj

You could plug in your adapter and check the voltage/amperage it's outputting with a multimeter. If that checks out okay, it may be a fuse in the twin famicom.

Lorfarius

Quote from: ericj on November 06, 2008, 12:06:19 pm
You could plug in your adapter and check the voltage/amperage it's outputting with a multimeter. If that checks out okay, it may be a fuse in the twin famicom.


Is it easy to replace a fuse in the console? What sort would I need? Never even attempted to open one up before so its all new to me  ???
My own Retro gaming YouTube channel: http://www.youtube.com/user/Lorfarius

133MHz

Quote from: ericj on November 06, 2008, 12:06:19 pm
You could plug in your adapter and check the voltage/amperage it's outputting with a multimeter.


Even easier, you can check that your AC adapter is working with your tongue. No joke. Just plug it in and put your tongue to the plug that goes into the Twin, trying to bridge the inner part with the outer part of the connector. If you can feel teh tingles, then it's working OK.

Note: This may not work if the connector's tip is isolated, and therefore, tongue-inaccessible.

turbo D

I once licked the end of a powerful ac adapter; not a pleasant experience! lol  :D
FC HVC-001 HC4593710 CPU-GPM-02 1989
FDS HVC-022 D1072158 FD7201P 6602 + new belt!
My FF setup!

Lorfarius

Quote from: 133MHz on November 06, 2008, 01:08:52 pm
Quote from: ericj on November 06, 2008, 12:06:19 pm
You could plug in your adapter and check the voltage/amperage it's outputting with a multimeter.


Even easier, you can check that your AC adapter is working with your tongue. No joke. Just plug it in and put your tongue to the plug that goes into the Twin, trying to bridge the inner part with the outer part of the connector. If you can feel teh tingles, then it's working OK.

Note: This may not work if the connector's tip is isolated, and therefore, tongue-inaccessible.


Yep I get the tingles!
My own Retro gaming YouTube channel: http://www.youtube.com/user/Lorfarius

133MHz

Then we move on, the problem is in the Twin itself.
It could be a fuse, or the 7805 power regulator.

Lorfarius

Quote from: 133MHz on November 06, 2008, 02:59:05 pm
Then we move on, the problem is in the Twin itself.
It could be a fuse, or the 7805 power regulator.


So crack it open. What should I look for?
My own Retro gaming YouTube channel: http://www.youtube.com/user/Lorfarius

133MHz

Can you take & post pics of the internals? Specially around the power and video connectors.

Lorfarius

Yep will do, thanks  ;D Will have to be tomorrow as its pretty late.
My own Retro gaming YouTube channel: http://www.youtube.com/user/Lorfarius

Lorfarius

November 07, 2008, 10:45:46 am #550 Last Edit: November 08, 2008, 01:17:35 am by Lorfarius
My own Retro gaming YouTube channel: http://www.youtube.com/user/Lorfarius

133MHz



I've circled the 7805 voltage regulator. It's the 3 pin device that's screwed to the big metal plate. With the Twin plugged in and powered on, check with a multimeter set on a low DC scale between pins 1&2 and 2&3. Here's some ASCII art I've just made to clear things up:

   ___
  |  o  |
|¯¯¯¯¯|   1 = Input (you should get anything from 7 to 20V from here)
| 7805 |   2 = Ground (place the multimeter's black lead here)
|_____|   3 = Output (you should get 5V here with a very small deviation)
| | | | | |
| | | | | |
¯  ¯  ¯
1   2   3

Tell us what you get.

Lorfarius

My own Retro gaming YouTube channel: http://www.youtube.com/user/Lorfarius

Lorfarius

First time Ive ever done anything like this so go easy on me! Putting the red pin between 1&2 and the black pin between 2&3 came back with 0 on the multimeter. However putting red to the left of 1 and black to the right of 3 came up with 20 on the meter. Couldnt get anything past 0 in the middle.
My own Retro gaming YouTube channel: http://www.youtube.com/user/Lorfarius

133MHz

You're doing it wrong. Let some more ASCII art explain things for you:

First, set your multimeter to a low DC scale (something like DC20V. DC could also be abbreviated by a line with three dots underneath). Second, your red lead should be plugged into VΩmA or something similar, and the black lead into COM. Plug your Twin, turn it on and try these:

Test 1:
   ___
  |  o  |
|¯¯¯¯¯|   
| 7805 |   
|_____|   
| | | | | |
| | | | | |
T  T  ¯
  |    ¯¯¯¯¯¯  Black lead here
  ¯¯¯¯¯¯¯¯  Red lead here
1  2  3


Test 2:
   ___
  |  o  |
|¯¯¯¯¯|   
| 7805 |   
|_____|   
| | | | | |
| | | | | |
¯  T  T 
      |    ¯¯¯¯¯¯  Red lead here
       ¯¯¯¯¯¯¯¯  Black lead here
1  2  3