Feedback Thread

[channelmaniac]

If you have feedback on this forum area please share it!

Is there something bugging you about the posts? Have these helped you? Am I leaving out important information? Is there something you have a question about that isn't answered here? Please let me know.

I post on these forums:

NewLifeGames.net
Neo-Geo.com
KLOV.com
pcenginefx.com (currently down)
and a couple more obscure ones...

And have fixed games for those forum members plus for customers off of my website. Many of these game boards have very little repair documentation available - no schematics, no troubleshooting guides, etc - just like the slots that most of the members here like to play with. This is my way of paying back the gaming community - posting how boards have been repaired and by posting how-to guides along with hardware documentation.

This thread is for the members here and anybody that found these threads by searching Yahoo!, Google, etc... who have found them helpful. It's also for folks that want to tell me if I make a mistake. All I ask is that people don't tell me it stinks but rather why it stinks so it can be improved.

Thanks,

Raymond

[Thor777]

WoW...The CoCO...I have one of the first (silver) units with cassette, single side 5" floppy drive (cost me hundreds at the time)...My favorite game was Dungons of Daggorth !!!

Mine is still working fine..although I did have to also take apart the keyboard for cleaning sticky keys...

BTW..I have the origional Technical Reference Manual for the Tandy 1000TL if someone ever needs it...and I'm sure I have it for the CoCo 1 but it might take me a while to dig that up

[tjkeller]

THANKS channelmaniac for sharing your knowledge and keeping this infomation a part of this forum!

[channelmaniac]

That was the computer I started with back in the early 80s. It was also my first shot at hardware hacking and repair. It brings back LOTS of memories!

The day it was out of warranty I ordered a 64k memory upgrade kit for $59.95 + shipping and installed it myself. (I was in middle school!)

A few months later I was building a custom game cartridge and plugged it in with the power on. OOPS. Dead computer. I ordered a replacement 6809E CPU and my uncle replaced it. It was soldered in so he removed it and socketed it as I didn't have THAT level of soldering skills then.

My uncle was one of the guys that helped to shape my life and love of electronics. He had a TV repair shop and showed me the finer arts of troubleshooting: Break down the circuitry into blocks and use your 5 senses. Breaking it down into blocks lets you narrow down where the problem will be. Using your 5 senses will allow you to notice things that could be the problem. These techniques work wonders when you don't have schematics. Master them and you'll be able to fix many different things. He was right.

I remeber my first lesson in this. I had a color TV that had no vertical output. It was nothing but a flat line on the screen. I had schematics but no idea were to start. I learned about the sections of a TV: tuner, power supply, IF, horizontal oscillator, horizontal output, vertical output, and the high voltage sections. In this case he said "Change this tube. Also, see this resistor? Check it. I bet you'll find it bad." He was right, it was charcoal. I replaced it and the tube and the set had a beautiful picture.

[Thor777]

BTW...Did ya all know there is a Emulator out their that can be used to run CoCo games and software on your current computer???

[channelmaniac]

Yup!

There are at least a couple of different ones including one written totally in Java. I used them to test some diagnostics software before deciding which version to put on an EPROM and build a cartridge from. It comes in handy when testing old hardware and chips.

[Thor777]

That was the computer I started with back in the early 80s. It was also my first shot at hardware hacking and repair. It brings back LOTS of memories!

The day it was out of warranty I ordered a 64k memory upgrade kit for $59.95 + shipping and installed it myself. (I was in middle school!)

OMG !!! ...  You mean the kit where you "piggyback " the memory chips !!!   I didn't wait for the warranty to run out...

Remember the POKE and PEEK commands...boy I was smart...hehe

[channelmaniac]

Nope!

I had the last revision of CoCo1, the NC board. It was the one that didn't have a letter designation on the board.

It required the removal of 8 4116 chips, removal of 8 capacitors (snip snip), moving of 3 jumpers, and soldering together two pads next to the SAM chip before installing 8 4164 chips.

Wasn't too bad at all.

Sad thing was, less than 3 years later Radio Shack was selling sets of 8 4164 DRAM ICs for less than $10 on one of their special purchase deals.

I miss those deals. They had a keyboard that was the same size/shape of the CoCo's but had real keys on it. It also had that flat plastic ribbon cable just like my NC revision CoCo1 had. I bought it. It fit and worked great! It had 2 function keys just like the CoCo 3 later came out with. My guess is that it was a keyboard they decided to not use on the CoCo 2. I loved having a better keyboard.

[SAT (aka GANDHI)]

Great!!!   

I like modifications a lot (as soon as they work same or better than original of course     )

I see myself posting in this topic in the future 

Question:  can any kind of mod be posted here??? just related to slots??? just related to electronics??? 

Cheers

[channelmaniac]

Actually, there's a whole forum subsection that anyone can post in for any topic - http://newlifegames.net/nlg/index.php?board=76.0

But nobody is actively using it yet...

Perhaps you could kick start it?

[SAT (aka GANDHI)]

Yeah for sure!!!  I'll give it a try cause i have some time now...

I'll search for some contents in my files 

[stayouttadabunker]

okay,
now....do you solder 1 resistor (rated at 150ohms) onto EACH  LEDs or do you only use 1 resistor (rated at 150ohms) for the whole string of LEDs?
I'm installing LEDs in a topper.
I need to use 50 LEDs to complete it.
I'm stringing the LEDs in a series configuration.
I am using household current (U.S.of A.)

Also,which leg of each LED does the resistor get soldered to?
The side that has the "bowl" or the other smaller side of the LED?
Or do I only use 1 total resistor for the entire topper string?

I don't know what these 5mm white LEDs need for power.
The only thing I know is that they emit bright white light using clear glass and the light isn't diffused (confused?)

I am....

Anyways, everytime I turn the power on....POOF! smoke escapes...
I end up checking every bloody bulb and resoldering the burnt out ones.
But for a brief second man....it is bright!

[channelmaniac]

All of the LEDs go in parallel. Then you add up the current needed to drive a group of them.

Why only a group? They'll all have slightly different resistances which means slightly different current draw and brightness. Doing them in small groups is better for that.

Take 10 of them for example... at 2.1v and 20ma each. That's 200ma total current draw off of, say a 12v power supply.

12 -2.1 / .2
or
9.9/.2 = 49.5 or 50 ohms. You could take 2 100 ohm resistors and put them in parallel for 50 ohms.

BUT WAIT! THERE'S MORE!

You'll need to also calculate the heat dissapation for dropping 9.9 volts across the resistors. If you use resistors that are too small they'll burn up. Those forumlas I don't have off the top of my head. I'd have to go look that part up.

RJ

[jay]

Are LEDs not normally 1.5v - so would you not string 8 of them in series and run them off of 12V ?
Alternatively if you then had 40 of these would you not then put 5 strings of 8 in parallel ?

[stayouttadabunker]

problem is: I don't know if these LEDs are 1.5V...there's no writing on them at all.
So, it's a crapshoot everytime I turn the power on...most times some LEDs go poof!
Then I gotta start all over again.

I actually have the same problem with xmas lights...you cant tell the difference between a 3.5V, a 6V or a 12V
bulb. You look at them and there's no writing on them either.
If you stick a couple of 3.5V replacement bulbs in a 12V string of say 150 bulbs....they get way too bright, hot and blow.

I'm becoming a master of blowing fuses and or xmas bulbs and LEDs???

[jay]

If your doing a lot of this kind of work I might suggest you get yourself either a fancy power supply that has a knob on it. That way you can start at 0 and vary your voltage upwards. A 12v bulb will just barely glow with 6v.
If you do a lesser amount you can probably pick up one of the voltage selectable wall warts from Radio Shack for like 12 bucks. It will do 3v, 6v, 9v, 12v by using a slide switch. Might save you some aggravation (and bulbs).

[stayouttadabunker]

sounds good . Thanks Jay...I'm going shopping!

[channelmaniac]

Are LEDs not normally 1.5v - so would you not string 8 of them in series and run them off of 12V ?
Alternatively if you then had 40 of these would you not then put 5 strings of 8 in parallel ?

The problem of putting a string of 8 in series is that they still would pull too much current. You have to limit the current or you'll pop 'em.

[Joeylc]

This is a good one .... 

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250299277978

[stayouttadabunker]

           $289.95 plus shipping  ....whew! For that price....it better be! lol thanks Joey.!

Let's say I use it as a yardstick for what I can afford....

[Joeylc]

          $289.95 plus shipping  ....whew! For that price....it better be! lol thanks Joey.!

Let's say I use it as a yardstick for what I can afford....

  Sorry about that I forget some times that this is just a hobby for some and 289.95 is kind of out of the ball park for just tinkering around.

I guess it's to many years of working in the casinos with unlimited budgets... 

This is a good one at a good price http://cgi.ebay.com/BK-1630-Power-supply-0-32VDC-0-3A-regulated-with-Meters_W0QQitemZ180321381745



 

[stayouttadabunker]

Thanks Joey....lol By the way, this the beautiful topper I'm working on....I finally got it to light up!
My workdesk is a little cluttered up...lol

Click on photo to enlarge it!

[jay]

RJ,

Help me here..... I think I need a Electronics 102 class (subtitled: How to Keep the smoke in)

I thought Current was drawn not pushed ?
I can see if you put a LED inline with a existing circuit it would be subject to the drawn load but if it was the only thing on the circuit how is it possible for it to draw too much unless the voltage is more than the device can handle ?

[jay]

Nice looking topper.

[stayouttadabunker]

Thanks Jay! (I wish it were mine though ...lol....I'm fixing it for a member)
It has a yellow/orange star too...I'm working on that at the moment!
Also has a blue column and it tops off with a two stage candle light.