nesdev.org

kevtris wrote:
This is 100% untrue. ...

prefer to use solid wire when making most things, because it stays in place better and doesn't flop around. It's easier to solder without having to tin the end of each wire to prevent loose strands flying around.

That is not what I discovered from my own personal observations in fixing dozens of these bad reproductions.

From the reproductions I saw that failed, they all had 30 gauge wire. Continuity testing the connections showed no resistance in the wire, but the game still didn't boot correctly (and yes, I did test from IC to IC and not wire end to wire end). When I replaced the 30 ga solid core with with a thicker stranded wire, the problems went away.

As far as soldering goes, I always tin all my wires before making a connection. I guess old habits; it doesn't add that much more time to the process, and I find the connections to be much better w/o future failure.

Personally, I don't want to eat shipping costs to a guy in Brazil, Finland, Australia or anywhere for that matter due to a solder joint failure 10 years down the road.

ok, what you say does make sense, kind of like how an electrical wire will loose amps the longer it is, but why would i get the game working with some chips and not others when using the same wire?

leonk wrote:

kevtris wrote:
This is 100% untrue. ...

prefer to use solid wire when making most things, because it stays in place better and doesn't flop around. It's easier to solder without having to tin the end of each wire to prevent loose strands flying around.

That is not what I discovered from my own personal observations in fixing dozens of these bad reproductions.

From the reproductions I saw that failed, they all had 30 gauge wire. Continuity testing the connections showed no resistance in the wire, but the game still didn't boot correctly (and yes, I did test from IC to IC and not wire end to wire end). When I replaced the 30 ga solid core with with a thicker stranded wire, the problems went away.

As far as soldering goes, I always tin all my wires before making a connection. I guess old habits; it doesn't add that much more time to the process, and I find the connections to be much better w/o future failure.

Personally, I don't want to eat shipping costs to a guy in Brazil, Finland, Australia or anywhere for that matter due to a solder joint failure 10 years down the road.

coinheaven wrote:ok, what you say does make sense, kind of like how an electrical wire will loose amps the longer it is, but why would i get the game working with some chips and not others when using the same wire?

Mostly because the way the wires are laid out have nothing to do with the problem on this case.

i was talking about the type of wire, i never switched it out, just replaced the chr ram chip

l_oliveira wrote:

coinheaven wrote:ok, what you say does make sense, kind of like how an electrical wire will loose amps the longer it is, but why would i get the game working with some chips and not others when using the same wire?

Mostly because the way the wires are laid out have nothing to do with the problem on this case.

coinheaven wrote:i was talking about the type of wire, i never switched it out, just replaced the chr ram chip

Well I am not a native english speaking person, perhaps I expressed myself badly. I really meant you kept the wires you were already using.

I find amusing when for example I show pictures of things I assemble with enamel coated wires and people start to complain about how I am using non insulated wire on the circuit. It's the fact that the wire is coated with enamel makes it insulated, but it surely does look like an naked copper wire.

That's aways fun.

"Behold the awesomeness of see-through insulation."

coinheaven wrote:ok, what you say does make sense, kind of like how an electrical wire will loose amps the longer it is, but why would i get the game working with some chips and not others when using the same wire?

There could be so many things that can cause this:

- bad ROM removal (causing shorts between pins - installing new CHR-RAM made the problem clear away due to 2nd cleaning)
- bad soldering (when soldering, make sure solder flows through hole and catches pin on both sides)
- wire stripped to much, to the point where tip actually touches 2 adjacent pins

What about the CHR enable? Are you using a cart with all pins, or are you faking it by adding metallic tape?

I have never ran into an SRAM chip that didn't work! And I've made A LOT of these games.

All reproduction failures I fixed were due to bad wire. When I replaced the wire, reproduction started to boot.

ok, i believe you, you are the godfather of repros! Ill see if another wire will work. where do you get your wire? i usually get mine from IDE cables i get from the junk store.

leonk wrote:

coinheaven wrote:ok, what you say does make sense, kind of like how an electrical wire will loose amps the longer it is, but why would i get the game working with some chips and not others when using the same wire?

There could be so many things that can cause this:

- bad ROM removal (causing shorts between pins - installing new CHR-RAM made the problem clear away due to 2nd cleaning)
- bad soldering (when soldering, make sure solder flows through hole and catches pin on both sides)
- wire stripped to much, to the point where tip actually touches 2 adjacent pins

What about the CHR enable? Are you using a cart with all pins, or are you faking it by adding metallic tape?

I have never ran into an SRAM chip that didn't work! And I've made A LOT of these games.

All reproduction failures I fixed were due to bad wire. When I replaced the wire, reproduction started to boot.

coinheaven wrote:ok, i believe you, you are the godfather of repros! Ill see if another wire will work. where do you get your wire? i usually get mine from IDE cables i get from the junk store.

I used to do that until I ran out of it.

The new IDE cable will not work. When they introduced speeds of >66mb/s they switched cable design. You need to use the older style (i.e. floppy drive cable)

Very interesting, I have always wondered why sometimes no matter what you do the repro does not work properly. I use network cable because someone gave me a 50 ft roll of it once. My only complaint being the coating on the wire melts back shrinks too easy.

marvelus10 wrote:Very interesting, I have always wondered why sometimes no matter what you do the repro does not work properly. I use network cable because someone gave me a 50 ft roll of it once. My only complaint being the coating on the wire melts back shrinks too easy.

These are made of rigid copper core, which is not a bad thing, but with conductors coated with plastic, it's possible that you might overlook an eventual crack on the conductor.

With enamel coated wires, should the wire break the coating is thin enough to break just along with the wire and that you can see it broke.

leonk wrote:
You can't use 26, 28, 30, whatever gauge solid core wire in making reproductions! I know it's cheap, but it's wrong. You have to use multi-strand wire. Years ago, I was using old IDE cable, but I now have a supplier which sells me spools of the wire. It resists cross talk better, and you can run it for longer lengths.

The problem with the CHR-RAM chip is the CHR enable wire. It's the longest wire in any reproduction (pin 56 on connector) and picks up a lot of noise, and feeds it into the CHR-RAM chip.

Sorry for the rant.. tired of fixing bad eBay reproductions.

What a crock of shit. Get off your high horse and pull your head out of your ass. Solid core wire has been used for this purpose in many types of electronics for decades you moron!

nintendo2600 wrote: What a crock of shit. Get off your high horse and pull your head out of your ass. Solid core wire has been used for this purpose in many types of electronics for decades you moron!

And the rats step out of the of the gutters .. welcome.

When you have reproduced next to 5,000 games in over a decade, then maybe I'll believe a word you say. Reading something in a book and doing it in real life are 2 different things.

I didn't believe it either, until I discovered it in person over the years. Continuity tests on 30ga wire shows perfect connections; removing the eproms and dumping them verified 100%. Replacing the wire caused the games to boot. Common sense would say it can't be so, but my experience showed otherwise.

Leon is not a moron. Crosstalk is real. But you're talking about something hard to see or measure since it happens in operation. If he's seen this problem in reproductions sent to him to fix, there is probably something going on there.

Because crosstalk is real and is a issue, modern equipment evolved from parallel buses into low voltage differential designs like for example PCI-Express. But then we're talking about gigabytes per second of transfer rates. At 1.75mhz crosstalk is a non issue, to be very honest.

If crosstalk was a issue, the "horrible" things I assemble would either not work at all or glitch a lot.

I'm not defending either sides, just citing that what was observed by leon could be something else, such as poor soldering (it's actually harder to solder properly single core conductors as the contact surface for the solder is smaller than that of a multi core conductor).

And 80 wire ATA cables do use single core conductors.