Resister repair before A/V mod ( IntelliVision )

Interesting. I went back to the store and they said that they are 2 watts. It doesn't matter the size anymore. They have 1/4 watt and 2 watt that look identical. I'm confused...

 

That doesn't sound right. Is there some other store you can go to? The 1/4w are more common so you may have a hard time finding 2w resistors locally. If they were all identical size, I don't see how anyone could tell them apart. They may have just put them out in the wrong spot on the shelf.
If you aren't in a hurry, you can order online to make sure you get the right ones.

 

I totally hear you. Actually when I had left I called back and said that exact same thing. "in the future, how would one tell them apart if they needed a 12 Ohm 2 watt or 1/4 watt resistor?". He said because of the bag they are in. He said my blown one that he saw was big because it was old.

I've only had the console back on for 5 minutes or so because I'm nervous of it blowing up. Anyway, I got the parts to make the AV mod. At least I can build that now. Tomorrow when I'm out shopping, I can go see if I can find some more. I wonder how I could test that??? Could I with a volt meter? or use the P=IR formula or something?

 

You need to employ basic repair procedures.

If you think a resistor is duff, test it! Get your multimeter out. Either it will read the right resistance, the wrong resistance or it'll be open or shorted. It's one of the most basic components to test - you can even do it in-circuit. As long as it's not in parallel with another resistor, of course. I would have said it's got a bit warm but is probably fine. Yes, you need to use the right wattage, or it'll burn.

Unless you're touching static sensitive devices, you are probably safe without an anti-static work area - and a piece of cardboard doesn't constitute one, anyway. As for discharging low voltage devices - unplug it, turn it on... it may come on for a brief second, then the power LED (if present) will go out. IT'S DISCHARGED. No need to wait several minutes - several seconds is too long.

Many LCDs don't do RF correctly, so it would be worth testing on a CRT or just doing the composite mod. I'd suspect that your television is the problem.

 

You cannot test it as far as I know. Were these all behind the counter or could you look at them? I am just wondering if all the resistors they have are the same physical size no matter what wattage rating they are.

From what I know carbon film resistors (which is what was in the console and what you bought based on what they look like) they use size to determine wattage rating. The bigger the size, the more heat they can dissipate. Unless there was some breakthrough on resistor technology in the past 10 years that I am unaware of. I think the guy at the store you went to does not know what he is talking about.

 

okay here is an update. I tested my Nintendo and my TG16 with the same RF cable and they work perfectly. I actually have a TurboBooster Express that works pretty nicely too. So I know my TV will handle the RF no problem, so now I know it is my RF modulator on my IntelliVision. About the resistor sizes. Today I bought all 1/4 watt resistors for the AV mod, and they are tiny... a lot smaller than the 2 watt I bought yesterday. I think we are safe on those. I'll just turn it on today for a bit and see what happens. I don't have a multimeter... I program PC's, not IC's. ;-)

About the static electricity. A lot of things can hold static or a static charge and I realize that. Cardboard being one of those too, but it doesn't do it easily. I just don't have access to anything better... was wondering if there was a make-your-own for home.

 

I'm here too now. I'm going to grab another one tomorrow if I can for parts.

 

Thanks for the tips big time!!!!

 

I know... he was kind of a @#$!@$# too. Well, I'll let it run for a bit and see how hot it gets at regular short intervals. Maybe I yank it out of there tonight.

anyone know where I can go and TRUST in the GTA?

 

Buy one online from a reputable company like mouser or digikey, unless you have a fry's nearby (even then, fry's is starting to dumb down like radio shack).

 

An anti-static mat is cheap if you want one - just get that with a ground plug (you'll probably be able to pick up a kit - mat, plug and wrist strap).

Resistor technology HAS advanced, yes... and it's possible to get slightly smaller higher wattage resistors. Not a lot, but a bit smaller. As I said, if the resistor measures OK, it's pointless changing it, anyway. If you really want to change it, I'd use a proper supplier - see my sticky for a list.


Just because one console works via RF, doesn't mean another will. If you can't test on a CRT, just do the mod anyway.

 

I'll see if I can get a mini-DC/AV volt meter to have with me anyway. I'm getting another resister today just in case so I should be good to go. Let's see what we figure out today. Thanks for all the help *retro*, *alexRMC92* and *mickcris*

I have 2 RF modulators on their way too. If I can pick up a working IntelliVision, I'll just tweak/mod the heck out of the one I have right now.

***
if you do pull a trace away from the board, as a work around (not best case scenario) can you follow where it was going and just solder a shielded wire between the two points?

aaron

 

Yes but I'd advise not doing that for a lot of reasons. I don't know about the Intellivision but engineers do design traces to be certain lengths and run certain ways with other traces nearby for various reasons. Probably not an issue in this case but it'd be a dumb thing to do since you're just grasping at straws at this point. I'd be a lot more curious to see what a scope shows on the power outputs for the console.

 

That hasn't happened yet. I was just asking if it did, what I can do as a quick fix. There are no trace problems right now. Also, if I did the work around, I would lay the wire along the trace so it was the same length (shielded of course)

 

Okay, since I have a mini analog multimeter that I have found ( HERE ) I can test the resistor that is on the board now that I replaced (debate if it is 2W or 1/4W). I know that voltage is across two points and current is through segment, where do I put the leads to test this Resistor?

 

So, no matter what happens of the resistor test, today I am either

1) keeping the resister (successful wattage tests) and doing the AV mod
2) changing the resister (failed wattage tests) and doing the AV mod

p.s. Does anyone know for sure if the white ribbon that is attached to the board I'm working on comes off temporarily? I can remove the other 2 power connectors, but I want to make sure on this one too.

 

This is where I have been getting my parts in case anyone knows of them or was wondering

http://nutechelectronics.com/

 

Lol, think before you post rather than quadruple posting! Or use the "Edit Post" button. It keeps things much easier to read.

You test a resistor by putting one lead on one leg and the other lead on the other. With the multimeter on one of the ohms settings. Not rocket science, that! Considering your limited knowledge, I would strongly recommend picking up a book on basic electronics - something like Electronics for Dummies would probably be a good read. It will really help you understand what you're doing - something that's vital when working with electricity!

Ribbon cables are generally removable, having some kind of clamping connector on the board, but proceed with caution as it isn't always the case.

 

Thanks! I've just cut the perf board in half as I'm going to make 2 of the AV mods. I have another IntelliVision I just picked up. I'll let you know how it goes.

@ retro - I posted in 4 posts so you could EASILY see the posts. It's sort of like grouping in SQL, no? Each block is about one topic, rather all together in one post. ;-) Elec-tro-tech For dummies, probably not. This is my one and only project of this type. I wasn't asking how to test the impedance of a resistor. That is obvious. In the context above, we were talking about the wattage. I was wondering where I could put the MM to see anything out of range that would indicate the problem (wrong power rating on the resistor).

I'm not just going to run the system and watch it pop in my face. Mr kirchoff said that wasn't fun. ;-)

 

just menioning, the original resistor shown on the picture was not broken yet. And it was just operating on the hot side for years. The brown stuff in it was some glue or rubber which was stuck on it and got burnt out from the resistor heat.

If you have it replaced, replace with one that has at least twice the potency of the original one, which obviously is kind of operating way too close to it's limit.