Dim Drive Light

[save2600]

LED's last for a very, very long time. You getting proper voltage readings out of your power supply? Power cable going to the drive good? Solder connections at the mobo good going to the drive?

[save2600]

The dim Drive light on the A500 was a Low pass filter function, it was an indicator of mode changes loading. I think it has something to do with the Extra Half Brite function in the newer Denise Chip. (A500 and A200 Rev 5 and later, not on A1000)

Shaf

Dim 'power' light indicates the audio filter bypassed - not the drive light.

[save2600]

I just recently put in an ecs agnus chip. Could that be it?

Agnus could care less about the power going to your disk drive. She told me so  

[save2600]

We need an Amiga Whisperer LOL. So, what should I do next?

RE-read my first reply  

[save2600]

I am not real good with a multimeter so you will have to walk me through where to put the probes (ie black and red) for measurement.

Oh boy. lol  Be careful you don't accidentally short anything out. First things first... red is positive, black is ground or negative.

First check the power supply not hooked to the Amiga. On the bottom of the supply, there is a legend that tells you what pins are responsible for what voltage. Be careful not to accidentally short your leads testing that and write down the results.

If you're spot on or extremely close, now present a "load" to the power supply by hooking it to the Amiga. Now you can place the black lead of the DMM To anywhere that's ground on the Amiga (any of the screws) or even the black lead going to the drive. Red to red, black to black. Comparing the with the notes you took, read if the voltage is much different. If so, you may have to re-build or get a new power supply.

Check to see if there is cold solder by "wriggling" the drive's power cable though. While a disk is spinning, apply pressure to the power cable at both ends (computer and drive, one at a time) and see if the light gets brighter or not. When I say "apply pressure", I don't just mean pushing down. Maybe pull up a little bit, twist it or bend the connector left or right. If the drive light gets brighter when you're fooling with the cable, then you have a bad solder joint that needs to be re-soldered.

If you suspect that new Agnus chip is at fault, maybe try removing her and ensuring all her pins are in the correct position. I guess it's possible that if one of her legs is shorting against another, you may experience a low voltage scenario too...

Lot's of various things to check! Welcome to vintage computer repair 101  

[save2600]

The computer works, but does this indicate a larger problem? Is it so bad if I just ignore it?

It's up to you whether you want to ignore it or not. I wouldn't be fine with it if it were my computer, but if you're not technically minded and you don't really care about diagnosing this thing, then yeah - I guess I'd just leave it and enjoy what you have for now while it still works  

[save2600]

It's all good! I don't mind helping out with the lighter stuff. And actually, I have a friend into Amiga now that's complained about some of these forums not being exactly "friendly" when it comes to questions. That a lot of Amiga people are kind of "snotty" that way compared to other computer enthusiasts. He's newly into Amiga and for the moment, he's avoiding subscribing to any forum for that reason. Hmm...  can't say I've ever noticed anything like that here.  lol

[save2600]

LOL! Whoa, now that's going back. 9v batteries are still sometimes called that because they were popularly used, perhaps originally designed for use in most of the first truly portable handheld transistor radios. Little bit of trivia for 'ya!

And no.... you will never get a reading touching both DMM leads to one DC pin. Black to ground and Red to positive.... always. Ground, minus or negative is what you're looking for.

http://www.hardwarebook.info/Amiga_500/600/1200_Power_Supply

[save2600]

Whaaat?     Well, there's a fuse inside of that supply - so hopefully that just needs to be replaced. Sorry man, but that was my very first cautionary rule - don't be shorting leads!!

[save2600]

Yeah, I guess I should get a pair of those. I swear the leads weren't touching! Wow, now save2600 has abandoned me. LOL Is there a chance  I didn't short it?

Oh He's back

Hey, a guys gotta eat you know! lol

Ummm... alligator clips are great, but I've found that unless you get some real small ones, you actually risk the chance of shorting a little easier in this case. Just my $.02.

So... did you plug it back in and retest?

BE CAREFUL!  =P

[save2600]

Come on now after my recent adventure you want ME to retest?

Alligator clips  are a good investment, so yeah - you'll need 'em sooner or later anyway. And don't test your power supply by plugging it into the Amiga after that high-pitched whine scare.  lmao

[save2600]

Do not plug that into your amiga! Power supplies are not supposed to hum, vibrate or whine loudly normally. That indicates something is wrong. Keep it turned on and keep the leads on the pins to ensure voltage is correct or not.

You know... if you swear you didn't short it, you know what? I bet that power supply just happened to take a dump on you and coincidentally, did it while it was not plugged into the machine. Fuses don't always blow and power supplies can and do (often) leak wrong current out of 'em when they fail.

I bet it's bad and you can count your blessings it didn't take your Miggy with it.    The dim drive light was a pretty good indication a component was starting to fail. It's all diodes and caps now buddy!  lol

[save2600]

So, the whining doesn't mean its going to blow up and kill me?

LOL! Nah.

[save2600]

There is an electronics shop down the street. They look like they repair pretty much anything. Should I take the psu down to him and have him look at it. I really feel like I shouldn't look inside a psu without knowing anything. I am a software guy!

Yep - that sounds like really sound advice at this point. PS for these machines can be had relatively cheap, so remember that before paying someone more than double-triple the cost of a replacement. I say double or triple because often, purchasing something that's been properly refurbished will last longer than something of this vintage that hasn't.

[save2600]

Good luck and let us know! Also, let them know what the stuff they may be working on is worth so that way, they know not to rape you on service. Mention that you'd like some preventative maintenance done too, like all electrolytic caps replaced. Same with the diodes/bridge rectifiers. Those things are small and they should be able to quickly give you an estimate.