Strange problem last night

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Channel 13 (the local Fox network here) just aired a story on those cheap plastic 6X power strips. They said at least half of them are illegal with fake UL approval stickers on them, and showed some video of them catching fire. They cut the cords from two different brands to show the wire is about 20 or 22 guage, which is way too thin to carry any type of load.

The best thing is to stay away from them altogether.
 
I use a ONEAC UPS unit that i picked up at an action pretty cheap ($500 for the set) in the studio it came with two battery packs and will run the studio for about 1 hour with everything running including the lights. This includes three computers, two printers, board, amps, compressors and effects units. Cutting the lights and just running the primary computer and recording gear I can get about 2 hours. It is an awesome unit but I haven't priced it to see what it would have cost me new. I was looking into buying a generator but even with that I still would have had a drop in power before the gen kicked in. with the ONEAC you don't even realize the power has failed.

The problem is the unit and battery packs weigh more than my complete system including the amps sub and speakers.

For gigs I simply use the regular Furman units.
 
Thanks Bob for resurrecting this thread. I was thinking about updating everyone.

After the suggestions and help from those that posted to this thread, I tested to try to isolate and determine what the actual problem was by first removing the power strip that I had been using and running on three different amps.

One amp, my RS 250 that had been given to me by a church is damaged internally, possibly by low power being fed into it by the bad powerstrip and it's REALLY, REALLY old. It cuts on and off and won't run continuously. I'm sad about that because it's a nice little amp and would be great as a back up which is what I was using it for. I need to find an audio repair company in the Tampa Bay area to see if it can be serviced and if it's worth fixing.

The second amp which I had originally thought was defective in some way, the Peavey PV1500, is working PERFECTLY. My only problem with it is it weighs around 50 pounds. It's also a bit underpowered and the clip lights flash on and off when I try to really crank things up. At low and moderate volume levels it performs just great. I'm anxiously awaiting the new line of super light weight and powerful Peavey amps that will be coming out soon. I'd really like to get a single amp that I can use to power my mains and my two little EV Sb122 subs. That means I need around 1200-1600wpc @ 4ohms. One amp means I don't need a 100lbs-150lbs or more amp rack to tote around.

The third, my Yamaha EMX512 powered mixer is functioning just fine also. I was very concerned that the low power from the powerstrip had damaged it in some way. This was the amp I was using when things went awry initially. I'm lucky nothing happened to it because it's my most used piece of equipment. By far the most reliable piece of audio gear I own along with my trusty EV Sx100+ speakers.

The conclusion to this saga?

The power strip I was using was bad, not the outlet at the VFW. I've performed there again with no power problems. I scoured ebay after the initial problem and starting this thread and I bought a Tripp Lite 1000va uninterruptable power supply. I got lucky and found one for $69 that wasn't bid up to a ridiculous amount. I figure this is comparable to a Furman power conditioner and maybe a tad better solution. It's heavy because of the internal battery, but it's not real bulky and it gives me some peace of mind.

I'm going to be building a heavy duty power box like DJBob's this week. In a previous life I did some electrical work so that won't be difficult.

Thanks to all who offered information, suggestions and support.
 
The Wizard Of OZ said:
One amp, my RS 250 that had been given to me by a church is damaged internally, possibly by low power being fed into it by the bad powerstrip and it's REALLY, REALLY old. It cuts on and off and won't run continuously. I'm sad about that because it's a nice little amp and would be great as a back up which is what I was using it for. I need to find an audio repair company in the Tampa Bay area to see if it can be serviced and if it's worth fixing.
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Sounds like either the voltage regulator in the power supply or a reservoir cap. Just a few bucks and some time for either.

Unfortunately, most electronic equipment bought today no longer includes a schematic- which used to come with ALL electronics. Therefore component recognition can be a big help.

If it's of any help, reservoir caps are usually the largest electrolytic on the board, and are usually found right after the rectifying section of the power supply.

Regulators can be a bit more difficult, as they might be in the form of a DIP IC, or a transistor package, or a multi-leaded can package. They are usually near the output, ( When I say near, or right after, I mean connection-wise) and will be found before any voltage splitting circuit. One pin will usually be connected to the high side before it, and the high will continue from another pin without another connection. There is usually a decoupling cap between the ground pin and the low trace. ( this would be a small ceramic, probably marked ".1" for .1uf). If you're very lucky, the regulator may actually be in a socket, and it's just pull and replace. As a matter of fact, if it is, it just may be loose- and the cause of your problem.

Just replacing one or both of these parts ( total of maybe $10 ) should solve your problem.
 
Hmmm, I have nothing to lose by opening the amp up and taking a looksee, might even learn something. I think I'll do that before I take it somewhere. I like to tinker and I have more time than money. Man, if I could fix it myself I would be so proud. Not likely, but what the heck, it's just a few screws.
 
dont forget to unplug power chord. I know from experience having switched out a blown Capacitor in one of my Peavey Decca 700's yrs ago. Got wired for sound right quick when attempting the removal of the Cap. I got blasted by that Cap, and I dont mean Capello.
 
Jon Tuck said:
dont forget to unplug power chord. I know from experience having switched out a blown Capacitor in one of my Peavey Decca 700's yrs ago. Got wired for sound right quick when attempting the removal of the Cap. I got blasted by that Cap, and I dont mean Capello.
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Capacitors will get you even if the power cord is diconected, you have to short them to discharge the first! The worst shock I think I ever had was when a friend of mine (well I thought he was) tossed me a charged cap out of a ham radio system. He had taped two wires from pos and neg post down the sides of the cap of course when I caught it it knocked me to the floor!
 
Thunder said:
Capacitors will get you even if the power cord is diconected, you have to short them to discharge the first! The worst shock I think I ever had was when a friend of mine (well I thought he was) tossed me a charged cap out of a ham radio system. He had taped two wires from pos and neg post down the sides of the cap of course when I caught it it knocked me to the floor!
Click to expand...

Electrician pranks.....they always start the same way.

"Hey, check this out"
 
Well, another update.

I know some of you think I'm an idiot. Oh well . . .

I said that my RS Optimus 250 was cutting in and out and it just wouldn't operate properly. I decided to open it up based on what JoeChartreuse said. I like to understand how things work and what's inside of stuff. I like new adventures. I like to at least try rather than just give up. Even if I fail, at least I tried.

So I remove a few phillips screws, took off the top cover-very easy to do. I looked inside and there was some dust, but not that bad considering the amp is probably around 20 years old(I guess)maybe more. I blew out some of the dust and brushed some of it off. Then I looked all over for something burnt or discolored-nothing.

The two large, black capacitors must be soldered on to the board because they wouldn't budge. I wiggled a few wires here and there to see if there was a loose wire or a cold solder joint that was obvious-nada. With the cover off I plugged in my mixer with a microphone.

I connected a speaker to each of the four binding post connector pairs-one pair at a time since I don't have any banana plug cables and the amp doesn't have any 1/4" outputs. All of them worked. I noticed that channel A worked alone, but channel B didn't-channel B only worked when both A and B buttons on the front panel were depressed.

Then I hooked up the laptop to see if the amp would work continuously with a music signal or if it would cut in and out like it had been doing. First I tried one speaker, then I tried one speaker on A-Left and one speaker on B-Right with both A and B attenuator knobs up full. Worked like a charm. I panned R and L going from one speaker to the other-worked fine.

I cranked up Pimp Juice and the sound was clean and crystal clear-it sounded terrific and loud too. With the volume up pretty high the clip light flashed from time to time when there was a hard bass note, but not continuously. For the small venues where I usually play at this amp is loud enough. I can't run subs with it, but it will run my mains just fine for now.

Why is it working now? I have no fargin idea??? Bizarre . . .
 
one thing is that though it might be free of dust but one speck. that Speck could be in the perfect location and cause issues. Think of a Car battery one bitty piece of rust can ruin the contact allowing your battery to interrupt the cycle.
Click, click click.
 
Well, whatever the heck it was, now the darn thing is working fine and believe me I'm not complaining, it's a fine backup amp and sounds just fine. I'm going to put the cover back on and run it again for an hour or two to make sure everything is fine. I might even take pictures of the amp innards before I close it up.
 
Brother Wiz,

The Optimus and Realistic PA amps are made by Gemsound and sold by Radio Shack. The model you have isn't likely to be quite that old ~ if memory serves, RS started selling the bridgeable 250 PA amps in the late '90s. That's around the time RS dropped the Realistic logo and went to Optimus.

That was after my time, lol. I got a couple of the earlier generation 100 wpc PA amps. I had a bit of trouble with them ~ one developed an intermittent power supply short and the other was cutting in and out.

In both cases it was due to poor solder joints. I found a nearly bridged solder joint in the one that was shorting. Fixed them myself and they worked fine for years afterward. Shirl's son still has one of 'em set up in his living room. :)

My main issue with these amps, they weren't powerful enough for a school dance. But they served fine for most other applications.
 
Fred Wright said:
Brother Wiz,

In both cases it was due to poor solder joints. I found a nearly bridged solder joint in the one that was shorting. Fixed them myself and they worked fine for years afterward.

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Which probably means that when Wiz wiggled the caps he made a better contact. The problem is that if wiggling fixed it, it can unfix it too. I would pull the board and re-solder those terminals, or figure to run into the problem again.

As for cap shocks, yes, they should be discharged, but not by direct short. A low ohm resistor should be used. Otherwise, the cap COULD blow the end cover. Also if the cap is good in the first place, discharging with the resistor will protect it.
 
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