Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: mickp elijah audio on December 15, 2016, 02:31:09 AM

Title: Crack working one minute - dead the next [Resolved]
Post by: mickp elijah audio on December 15, 2016, 02:31:09 AM

Hi all , first post and as a tube newbie, I will no doubt be returning for more help
I bought a standard Crack secondhand - and had to do a bit of resoldering to get the right channel working
I am blown away by the sound through my also recently purchased HD 650's
Tonight's issue (midnight , Adelaide , Sth. Aust)
Used the Crack last night, and switched it off when finished - went and turned it on tonight - DEAD - The fuse is OK
Any ideas why it would behave like this ??
Thanks for any help
Michael Parin
CEO Elijah Audio

Title: Re: Crack working one minute - dead the next
Post by: Tom-s on December 15, 2016, 04:32:44 AM

Perform resistance and voltage checks.

Title: Re: Crack working one minute - dead the next
Post by: mickp elijah audio on December 15, 2016, 04:42:50 AM

Thanks, but I thought those checks were only performed to get a new Crack working
Mine has been working OK for 2 weeks and  now won't fire up
Does it mean something , e.g. the transformer, has died ??

Title: Re: Crack working one minute - dead the next
Post by: fullheadofnothing on December 15, 2016, 06:34:53 AM

If something was wrong with the transformer, it never would have worked in the first place. The odds of getting a bad transformer are essentialy zero. When we have had problems with transformers, the problem has been traced to improper installation damaging the transformer, and not a defect in the transformer.

Your problem is almost certainly a poor solder joint that has expanded and contracted with heat from being turned on and off. Resistance and voltage checks will help locate the problem.

Title: Re: Crack working one minute - dead the next
Post by: mickp elijah audio on December 15, 2016, 08:08:07 AM

Thanks - as I have already had to fix a few dud  solder joints - this is good news
I will report back ASAP
Thanks again

Title: Re: Crack working one minute - dead the next
Post by: Doc B. on December 15, 2016, 08:13:29 AM

Check that the power switch contacts are actually closing with your DMM. Sometimes the switch is damaged when installed and makes intermittent contact.

Title: Re: Crack working one minute - dead the next
Post by: mickp elijah audio on December 15, 2016, 12:26:03 PM

Thanks to all - sweet music again
I reflowed a couple of joints on IEC socket  and also clipped a couple of bare wires that were very close to neighbouring wires
Not sure which one did the trick, but I am a happy camper once again  :)

Did you hear about the farmer that won the Nobel prize?
He was out standing in his field.............
Thanks again