For whatever reason R226 (pos lead) popped and the piece flew off damaging L200 (red circle), a piece of its' insulation is missing and at least one wire is open underneath, resistor is no problem, service manual calls for a .5mhy coil
The coil on the other channel measures ~ 7ohms in cct, the damaged one measures ~ 48ohms
I tried searching for .5mh and 500uh axial coils/inductors with ~ 7ohm resistance and not having luck finding a suitable replacement... anything I ever knew about a coil I've certainly forgot sometime in the last 25 years or so... can anyone help finding a replacement?
The coil on the other channel measures ~ 7ohms in cct, the damaged one measures ~ 48ohms
I tried searching for .5mh and 500uh axial coils/inductors with ~ 7ohm resistance and not having luck finding a suitable replacement... anything I ever knew about a coil I've certainly forgot sometime in the last 25 years or so... can anyone help finding a replacement?
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Wow! Without any schematics it's a rather tough job to tell 🙄!
Did you find out what had made the resistor literally explode?
Best regards!
Did you find out what had made the resistor literally explode?
Best regards!
L200 is in parallel with R230, 47 Ohms, making L200's resistance look lower than it really is. You need to lift one end of the inductor to get it's real DC resistance.
If you still can't find a suitable replacement go to the Crown website and do a parts request. Crown used to be very good about spare parts, if not original they usually had a sub. BUT, big BUT they are owned by Harman now and support usually goes out the window when that happens.
If that fails I have an old DC300 that's not going anywhere, it's been in pieces for close to 20 years, I'll pull the part and send it to you.
Craig
If you still can't find a suitable replacement go to the Crown website and do a parts request. Crown used to be very good about spare parts, if not original they usually had a sub. BUT, big BUT they are owned by Harman now and support usually goes out the window when that happens.
If that fails I have an old DC300 that's not going anywhere, it's been in pieces for close to 20 years, I'll pull the part and send it to you.
Craig
I have the schematic from some old DC300 threads on solid state forum.
Take 11 turns of wire, 16 ga, wrap around a AA battery or a china marker. Take out the battery or china marker. Solder to board. Teflon wire has thinner insulation if you're worried about the turns not being as close together as original. They use magnet wire but having a roll of magnet wire laying around is not much good for anything.
If 11 turns of wire doesn't match what you have, match what you have. My Peavey inductors are 15 turns and .8 mH I think.
Take 11 turns of wire, 16 ga, wrap around a AA battery or a china marker. Take out the battery or china marker. Solder to board. Teflon wire has thinner insulation if you're worried about the turns not being as close together as original. They use magnet wire but having a roll of magnet wire laying around is not much good for anything.
If 11 turns of wire doesn't match what you have, match what you have. My Peavey inductors are 15 turns and .8 mH I think.
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@Kay Pirinha no I didn't look yet the cause of R226 popping, difficult without a schematic and not sure I could interpret it with 100% accuracy
@llwhtt thank you for the hint, I emailed Crown and will wait to see what they say, and thank you for the offer!!
@indianajo thank you!! While I'm waiting I'll try like you said!
@llwhtt thank you for the hint, I emailed Crown and will wait to see what they say, and thank you for the offer!!
@indianajo thank you!! While I'm waiting I'll try like you said!
These are ferrite core inductors about the size of a 1/2W resistor, 16AWG is a bit much.
3510 is the old Crown part number if you don't have it.
Craig
3510 is the old Crown part number if you don't have it.
Craig
@indianajo: I don't believe that it's an output inductor. The resistor it is wound on looks too small for this purpose. Rather I think that it's a multi-layered cross-wound inductor that has been dipped in some compound or wax. But I really have no clue 'bout it's purpose without schematics.
Best regards!
Best regards!
The Crown schematic is actually a pc board layout, and is illegible.
Anyone have a useful schematic?
L200 is a small inductor, the coil is made with thin enameled(insulated) copper wire and now your induction coil is open circuit by the damage.
If you can't buy part from any vendor, you can try to repair or rebuilt the coil.
Repair - desolder the inductor off the PCB and carefully try to get the broken wire both side a little bit out of the coil and try to connect them together by soldering a wire between, since the wire is enameled(insulated), so that you have to remove the enameled on the wire by sand paper where you need to solder.
Rebuilt - if the inductor damage so bad, you have remove all the coil wire for the inductor and you measure the wire diameter(wire gauge) and buy the same enameled copper wire and an inductance meter(not expensive) to rebuilt the coil, the finished coil can be covered by a heat shrink tube.
The schematic can check with 300A series II, they are very close.
Crown DC-300 - Manual - Dual Channel Laboratory Amplifier - HiFi Engine
If you can't buy part from any vendor, you can try to repair or rebuilt the coil.
Repair - desolder the inductor off the PCB and carefully try to get the broken wire both side a little bit out of the coil and try to connect them together by soldering a wire between, since the wire is enameled(insulated), so that you have to remove the enameled on the wire by sand paper where you need to solder.
Rebuilt - if the inductor damage so bad, you have remove all the coil wire for the inductor and you measure the wire diameter(wire gauge) and buy the same enameled copper wire and an inductance meter(not expensive) to rebuilt the coil, the finished coil can be covered by a heat shrink tube.
The schematic can check with 300A series II, they are very close.
Crown DC-300 - Manual - Dual Channel Laboratory Amplifier - HiFi Engine
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@patrick101 yes that was my very first thought but was in abit of a rush setting up.
I just had another look with my mini magnifier and removed abit more of the coils' outer insulation in hopes to reveal the break point, gonna need another set of hands to help but it just *might* be doable with an individual strand from some scrap wire, will post pics of my success/failure lol
I just had another look with my mini magnifier and removed abit more of the coils' outer insulation in hopes to reveal the break point, gonna need another set of hands to help but it just *might* be doable with an individual strand from some scrap wire, will post pics of my success/failure lol
You can fix the inductor by soldering it to a plain surface, in the way that you can spare your hands to access the repair job.
Sayal Electronics in Canada has stock number JAA-392-1
470uH(.47mH) 10% Good fit for L200, L100, L202 & L201
I used very similar in my past repairs on the DC300... worked fine.
Those coils are part of the over current protection scheme.
BTW, HiFi Engine is a good source for audio schematics.
470uH(.47mH) 10% Good fit for L200, L100, L202 & L201
I used very similar in my past repairs on the DC300... worked fine.
Those coils are part of the over current protection scheme.
BTW, HiFi Engine is a good source for audio schematics.
You got banned from HiFi Engine? That only happens when you spoof your IP and exceed the download ration. Ha ha there is always an alternative approach and failing that you could try Audio-Circuit [.dk] – No. 1 free Audio Schematics & Service Manual download site Funny, Jan, the host of my link also knows about the DC300' series. Good luck but I think Jan will also ban you if you exceed the download limits on his site as well. There are a few more sites with massive archives...
Crown is owned by Harman, but the bigger issue may be that Harman is owned by Samsung. My guess is that Crown is not the reason why Samsung bought Harman. I suspect that they wanted JBL and AKG for the headphones and "Lifestyle" audio products. Just a guess, and I'm really not a business person, but something tells me that it wasn't the likes of Crown, Studer or BSS that got Samsung's interest.
I guess you're Right. In the past when Harman was a stand-alone company, representing JBL among others in Europe, they were very helpful.
Best regards!
Best regards!
The DC300 schematic is on here, solid state forum, in a thread titled crown DC300. But search engines are useless. I tried bing, using "diyaudio.com😀C300 schematic" . It found this thread that doesn't have it, a thread in tubes and valves forum, a thread about a DC300 clone, and a 2006 thread about a DL115 schematic from some other company.
The smiley face above is really a colonletterD What idiot replaced colonletter D with a graphic?
The smiley face above is really a colonletterD What idiot replaced colonletter D with a graphic?
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And Crown of today is not Crown of yesteryear, by any stretch of the imagination. And neither is Crown of even 10 years ago. Modern crown is just like everybody else’s cheap amp (except maybe Behringer and Pyle and American DJ and the like) which stoop to even lower lows).