Crown CE1000 channel 2 problem/fault indicator -diagnosis

Thread Starter

wolf1419

Joined Nov 1, 2008
117
Hello Ron,

About the diodes:
The 1N4007 is a higher voltage version of the 1N4004.
That will work fine in the amp.

About the capacitor:
The working voltage must be the one stated in the schematics.
The 35 Volts can be used. A 50 Volts version may even be better.
(I am in favour for the High temp types).
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=020-1670
Perhaps change C4 too, that is of the same age.

I alway use a capacitor that is rated 1.5 times the working voltage or higher.

About the LM234:
I asked to check the 57.6 K (R190 / R290) resistors before, but the 226 Ohms resistors can be checked too.
(you said you had no access).

Greetings,
Bertus

PS Digikey and Mouser are also very good part suppliers:
http://www.digikey.com/
http://www2.mouser.com/Home.aspx
There you will also find a lot of SMD parts.
IN4007 it is...confirmed

C4/C5 = 24V x 1.5 = 36V(thus 35V by design)....is bigger(50V=24V x 2.1) always better, or is that a condition where using an extra strong cap, etc....could allow "more components" to burnout if a spike occurs....?
(Just asking to understand why certain values are chosen by design)

I'll check digikey & mouser also......I've checked them for other parts, but thought they had large minimum orders, more suited to big business, but I could be wrong.....I'll check them out again....and I couldn't find Crown parts online, but found their policy on page 5-3......tough doing things by phone here(press 1, press 5, wait, wait.....no humans avail..??)

Yes, you are correct about checking resistors around LM234(also D119 - page 3-6), so we are of the same mind here, and correct, I had no access......the board will have to come out for that, and probably to do D1-D4, C4/C5 if I'm not mistaken, as these are not SMD, and would be soldered from the rear.....correct..?

Can I do a workaround to just remove those 6 components from the top, temporarily wire these 6 new components with wire extensions, and see if I get back to my original operating condition(before the latest Blowup) to see if I ruined anything else, or should I just open it all up and "dig in"......as other components "may" have been Fried as well........? To powerup with board out I may need the service kit wire extension pack(page 2-3,4)......any way around that..?
 
Last edited:

bertus

Joined Apr 5, 2008
22,118
Hello Ron,

The use of a capacitor 1.5 times higher than the voltage applied is a kind of common practice.
Taking the next higher voltage will make the capacitor last longer, as the dielectricum can stand more than it is used at.

For the "temporary" mountng;
You can cut the diodes near the bodies and solder the new diodes on the old legs of the old diodes.
I do not know how the capacitors where mounted, but you could try the same method.

If the capacitors and diodes are in place you can see if the stabelizers still work.

Greetings,
Bertus
 

Thread Starter

wolf1419

Joined Nov 1, 2008
117
Hello Ron,

The use of a capacitor 1.5 times higher than the voltage applied is a kind of common practice.
Taking the next higher voltage will make the capacitor last longer, as the dielectricum can stand more than it is used at.

For the "temporary" mountng;
You can cut the diodes near the bodies and solder the new diodes on the old legs of the old diodes.
I do not know how the capacitors where mounted, but you could try the same method.

If the capacitors and diodes are in place you can see if the stabelizers still work.

Greetings,
Bertus
OK, that's why I asked....you are the voice of experience....I'll go with the 50V caps...confirmed......and your workaround about leaving the legs in place sounds a lot better than what I was envisioning......the caps appear to be very, very close to the board.....that might be a bit tougher to do unless I can "cut" my way to the lugs....I'll have to send for parts.

What do you mean by the "stabilizers"...is that the startup 4 seconds, or something else...?
 

bertus

Joined Apr 5, 2008
22,118
Hello Ron,

With the stabelizers I mean U1 (MC7815 or LM7815) and U2 (MC7915 or LM7815).
Those are chips 1A voltage stabelizers to "stabelize" the 24 Volts input (wich still has a hum on it) to 15 Volts output.

Greetings,
Bertus
 

Thread Starter

wolf1419

Joined Nov 1, 2008
117
Yes, U1 & U2...that's where I was measuring when the "short" occurred...is there a confident way we can check other suspect components that might be blown by my "error".......so I can order most everything at once......;).....at least the things you would suspect at this stage......
 

bertus

Joined Apr 5, 2008
22,118
Hello Ron,

It depends on the place you made the "error".
At the moment I do not know what other parts might be affected.

Greetings,
Bertus
 

Thread Starter

wolf1419

Joined Nov 1, 2008
117
Hello Ron,

It depends on the place you made the "error".
At the moment I do not know what other parts might be affected.

Greetings,
Bertus


I just got some bad news from Crown...they don't make the wire extension kits(obsolete)to open it and run "live"(Section 2 page 3,4)....but I did confirm date with them = April 1999, they couldn't tell me which board, but it agrees with my research that it should be board 102138-9, Rev B(w/bootstrap R 1k/5w installed, components, etc.. P123-144) of January 28, 1999, and schematic "M"(P561-564)....so that's the good news..at least I know what sheets/parts to reference....

My "error" was measuring the V in(-24V) at U2 and it sparked right there, assuming it might have grounded to the metal cage(heat shield..?) around U2....you may see it if you zoom into the pictures I posted....
 

Thread Starter

wolf1419

Joined Nov 1, 2008
117
Hello Ron,

When you are lucky the stabelizers are still OK, as the short was made before them.

Greetings,
Bertus
Let's hope that's the case.........it looks like I'll be ordering D1-D4, C4/C5, with spares of course, do some static checking in the meantime.....then get D1-D4 & C4 in there temporarily and see if it comes back to where we left off...........before I take anything else apart....and if all is where we left off(verify we have the same voltages), I'll pull it apart and go for resistors around U106/U206, etc......:cool:

That will give you a long deserved break and I'll get back to tinkering with some guitars in the meantime...... :D
 

Thread Starter

wolf1419

Joined Nov 1, 2008
117
Hello Ron,

I will see you later.
Have a nice play on your guitar using the 8100.

Greetings,
Bertus
I have some minor repairs to do with connectors, minor renovations on a few amps(tolex, connectors, etc...) & guitars(finish knicks, scratches, wet sanding, polishing), some disassembly and wiring fixes that I do for a hobby, when I'm able, as amatuer collector of used musical equipment, to keep me slightly active and engaged between bouts of CFS. I will be playing some guitar thru the 8100 also, thanks to your guidance. I'm slowly, but surely, gaining a feel and appreciation for electronics....I'll get back when I get parts and see what develops.... Thanks, Ron
 

Thread Starter

wolf1419

Joined Nov 1, 2008
117
I just ordered the 1N4007 diodes and Elna(same "brand" as Crown CE1000) 470uf/50V/85 caps(they are a little bigger(diameter), 35V just fits(12.5mm vs 16mm), I think hi-temp 105's are even bigger in physical size...very, very tight space)...hopefully they can sit a little higher off board if needed to fit if I have to...there's no clearance, but found out after they were already ordered....OOPS!!!...;)
Also, I got a great deal on a Sturtevant Richmond 36/4 810587(2-36 in/lbs) torque screwdriver so I can open this up and reassemble with proper tools......it's nice to have good tools available for future needs also. I may have to design my own DIY wire extensions if needed, for "live access" and testing, etc......:cool:
 

bertus

Joined Apr 5, 2008
22,118
Hello Ron,

If you want to make the extensions cables yourself, take wires of the same size or thicker.
It would be nice if you could find the same connectors used in the amp.
I saw there was a picture of the setup with the extensions cables in the manual.

Greetings,
Bertus
 

Thread Starter

wolf1419

Joined Nov 1, 2008
117
I have pic on page#1 of this thread that shows my connector...and Crown data from service manual....
I may have found the plug 102202-1 HDR SHRD 4 pin PCB mount by AMP(based on Crown parts list description).......don't have "small guy" supplier yet either..
https://www.sierraic.com/datasheet.asp?part=1022021
Research at amp has this part as the mate, 487769-2, even though it "looks" different than my pics.....
http://www.tycoelectronics.com/cata...BYPN&BML=&LG=1&PN=487769-2&PID=18467#features
The other option(if I can't find a direct match) would be to cut the wires and use "butt end connectors", or something similar to extend and then butt them back together, or try to remove the wires from the original connector, extend wires and use the same connector somehow(but if it breaks, I'd be out of luck)...any thoughts here.....or exact match plugs..?
 
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bertus

Joined Apr 5, 2008
22,118
Hello Ron,

You could cut the wires to make them longer by putting a piece of wire in between.
You can isolate the solderjoints using shrinking isolation tubing.

The longer wires can stay in the amp when you use a thicker wire to enlong it.

Greetings,
Bertus
 

Thread Starter

wolf1419

Joined Nov 1, 2008
117
Hello Ron,

You could cut the wires to make them longer by putting a piece of wire in between.
You can isolate the solderjoints using shrinking isolation tubing.

The longer wires can stay in the amp when you use a thicker wire to enlong it.

Greetings,
Bertus
Bert,
Thanks, that sounds like a very good idea(no matching of connectors, potential breakage, etc.).......the extra wire would already be in there whenever it needs service(too bad the Co's. don't think of that in the first place), just in case it takes me a few times to get this all working properly.....my other parts(diodes, caps) just arrived.......so I know how to proceed.....cautiously!!
 
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jjbelair

Joined Mar 11, 2013
1
I know this is old thread, but you two have been an immense help to me in solving the same problem on the same amps. 2 of my CE1000's failed like this, without observable cause, between uses... one both channels at once, the other, channel 2 only. I can assure you your efforts were worth it, because when I called Crown (I live within 100 miles) they offered to fix any problems encountered for a flat $250 regardless of parts and labor. That's $500 for 2 of 'em. I had gotten into the the fault circuits as the probable culprits but have gotten much further with the insights in your exchanges. But, I got more time than money, and love to learn about this stuff. thanks, -jjbelair-
 
Hello Ron,

Congratulations with your birthday.

I have looked at the service manual and saw there are some field modofications in chapter 9.
One of them is for a constant blinking led, some timing has to be changed and some parts to be changed.

The parts involved are SMD (surface mount devices) that need some care to handle.
http://www.circuitrework.com/guides/7-0.shtml

Greetings,
Bertus
Bertus i I realize this is an old post but I have the same model amplifier. And I'm unable to find a service manual where is it that you obtained the copy you were reading please sir. Im having a similar issue except all the lights and display. on the front of mine are flashing off and on when i power it on.
 
Hello,

Did you see the schematic in the first post of the thread?

Bertus
Yes sir i have that...i must of miss read your post because from my assumption from what I read I took it that they were several chapters or pages to this service manual. The manual in found and download has 7 pages in which 5 are blank the other 2 contain digrams. I was thinking a service manual has text and some sort of troubleshooting guidance. Im i mistaken? Or wrong terminology?
 
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