Welcome, Guest. Please Login or Register
Decware Audio Forums
10/25/14 at 08:22:55


Pages: 1 2 
Send Topic Print
Help,no power on left mono (Read 4647 times)
Steamer
Ex Member



Help,no power on left mono
01/05/06 at 17:24:29
 
Hello,
Went to power up system this am and I have no power on left se84cs mono.

I have verified power at the power cord at back and checked fuse with multimeter.

What is my next step,tubes? if so which one?

Thankyou for any help,
Greg
Back to top
 
 
  IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #1 - 01/05/06 at 17:39:05
 
Have now replaced all tubes one at a time,same result

I ran the amps for 18 hrs yesterday and did normal shutdown Decwares first to my source,saw no flashes or any indication of something wrong.

Greg
Back to top
 
 
  IP Logged
Chris K
Ex Member



Re: Help,no power on left mono
Reply #2 - 01/05/06 at 18:22:01
 
Does the rectifier tube filiment light?
Do the other tubes light?
You say no indication of something wrong so I assume they do.
Back to top
 
« Last Edit: 01/05/06 at 18:23:09 by Chris K »  
  IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #3 - 01/05/06 at 18:52:47
 
none of the tubes light up,I saw no indications as I shut the system down
Greg
Back to top
 
« Last Edit: 01/05/06 at 18:55:57 by steamer »  
  IP Logged
Steve Deckert
Administrator
*****


If the 1st watt
sucks why continue?

Posts: 2425
Re: Help,no power on left mono
Reply #4 - 01/05/06 at 19:10:41
 
If none of the tubes light up then you have a blown fuse.  If the fuse blows every time you turn it on the most likely cause is a bad rectifier.  To find out simply power the amp on without any tubes and see if the fuse blows, if not the amp is probably fine.

Steve
Back to top
 
 
WWW   IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #5 - 01/05/06 at 19:26:21
 
Thankyou steve,I checked the fuse with a mulimeter but did not replace,I have extras and will try that.
The suspect fuse was compare against a known good one with the same result on the meter so I thought it was good
Greg
Back to top
 
 
  IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #6 - 01/05/06 at 19:30:04
 
Just replaced the fuse and still no power or tube illumination

Greg
Back to top
 
 
  IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #7 - 01/05/06 at 19:38:27
 
BTW what would I see on the meter for ohms when testing a bad fuse?
I tested 6 fuses with the same results,8 ohmfor all(2 amp fuse)

Greg
Back to top
 
« Last Edit: 01/05/06 at 20:00:39 by steamer »  
  IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #8 - 01/05/06 at 19:59:46
 
ok I just tried to power the amp on without tubes and then checked the fuse,it was good

Greg
Back to top
 
 
  IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #9 - 01/05/06 at 21:23:49
 
Guess I have to look inside.
What should I look for?
I would think loose wires,power switch,possibly a bad transformer,any suggestions?

Greg
Back to top
 
« Last Edit: 01/05/06 at 21:25:29 by steamer »  
  IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #10 - 01/05/06 at 22:09:47
 
Well found the problem.

Had a look inside and found a broken solder joint at the power on switch.

My question is on the switch there are 6 connections and I see number labeling 1-3 for solder points #1 being soldered to wire from the power cord,which other one do I solder to,2 or3,can I test the switch to determine this?

It looks like the #2 post was the broken solder joint,just want to be sure as I am off to the hardware store and will do my first solder joint tonight because I cant stand the silence any longer...havin serious withdrawls!!!!!!!!!!!

Greg
Back to top
 
 
  IP Logged
selmerdave
Ex Member



Re: Help,no power on left mono
Reply #11 - 01/05/06 at 22:48:38
 
Greg,

Just be *sure* to discharge those power supply caps before going in there.

Dave
Back to top
 
 
  IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #12 - 01/06/06 at 00:14:58
 
[quote author=selmerdave  link=1136485469/0#11 date=1136501318]Greg,

Just be *sure* to discharge those power supply caps before going in there.

Dave [/quote]

Dave,
Thanks for the warning,the amps never had power to them today but I was careful to not touch anything but the job at hand.BTW how do you discharge the power supply caps?

Well it works,probably not the best solder job in the world.I verified the proper connection(#2) with a meter,with switch in off position #2&3 showed no potential,with switch on only post #2 had potential(I think that is the correct term).

As it turned out the power switch was loose and I knew it before the problem.It dawned on me that every time I would power up or down I could be moving that joint back and forth.The switch is now tight!

Thankyou everyone for the help,
Greg


Back to top
 
 
  IP Logged
selmerdave
Ex Member



Re: Help,no power on left mono
Reply #13 - 01/06/06 at 01:00:00
 
Greg,

You can just short them but I think the better way is to short them with a high-wattage resistor, mine is around 1k 5W.  Of course make sure you have some *well* insulated leads on the resistor.  Before I got the resistor tip I used to use a length of coax, one time I was bleeding them after being off for almost two days and there was a giant blue spark that was so loud I heard ringing in my ear for hours, and it was three more sparks before it was fully discharged.  Those are some serious caps and it only takes one of those experiences to create a vivid imagination of what would happen were they not discharged.

Dave
Back to top
 
 
  IP Logged
Steamer
Ex Member



Re: Help,no power on left mono
Reply #14 - 01/06/06 at 03:36:58
 
wow,
2 days.thought i was safe after 18 hrs,a lesson to remember.
Greg
Back to top
 
 
  IP Logged
Pages: 1 2 
Send Topic Print