Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: spiral2012 on February 05, 2015, 08:59:34 AM

Title: Snapped mje5731ag lead
Post by: spiral2012 on February 05, 2015, 08:59:34 AM
Just bought a used crack and once of the MJE leads broke during shipping.  Is there a way to resolder it or do I need a new one.  The lead broke where it meets the board.  The remaining lead is after the taper and too thick to insert in the hole.  Any help is greatly appreciated.
Title: Re: Snapped mje5731ag lead
Post by: Paul Birkeland on February 05, 2015, 09:08:40 AM
Is this on the MJE350 or TIP50?  If it broke at the board, just apply a tiny bit more solder.

-PB
Title: Re: Snapped mje5731ag lead
Post by: spiral2012 on February 05, 2015, 11:23:53 AM
I believe it's the MJE350.  Worried the lead pieace in the board would fall out or the connection won't be strong enough.   So just add a bit of solder from the top side and leave the broken piece in place?
Title: Re: Snapped mje5731ag lead
Post by: spiral2012 on February 05, 2015, 11:28:08 AM
Here's a better image.  Yellow line is where it snapped.
Title: Re: Snapped mje5731ag lead
Post by: Nathan on February 05, 2015, 12:24:33 PM
Mouser has this part for under a dollar. I would look to replace the part.
Title: Re: Snapped mje5731ag lead
Post by: fullheadofnothing on February 05, 2015, 01:52:13 PM
That looks solderable, but you'd have to try it to find out.

It is worth noting that it's not the stock part, and neither are the visible resistors. The larger resistor on the small board is quite clearly the wrong value, the small one isn't legible, so I can't know. Did your seller disclose the nature of the modifications he did?
Title: Re: Snapped mje5731ag lead
Post by: spiral2012 on February 05, 2015, 03:16:54 PM
That looks solderable, but you'd have to try it to find out.

It is worth noting that it's not the stock part, and neither are the visible resistors. The larger resistor on the small board is quite clearly the wrong value, the small one isn't legible, so I can't know. Did your seller disclose the nature of the modifications he did?

This was apparently one of the first speedballs, built in house by BH.  Here's the link to the original listing.  https://www.head-fi.org/t/670457/sold-limited-edition-bottlehead-crack-speedball-mint-condition-price-drop (https://www.head-fi.org/t/670457/sold-limited-edition-bottlehead-crack-speedball-mint-condition-price-drop)  Changed hands a couple times before I got it.  Everything looks the same as the OG picture though.  I'm assuming the guys at BH changed some parts when they decided make this a regular production part.  I could be wrong though.  Any issues you see with the parts in the listing pic?  Many thanks!
Title: Re: Snapped mje5731ag lead
Post by: spiral2012 on February 05, 2015, 03:33:57 PM
More pics
Title: Re: Snapped mje5731ag lead
Post by: Doc B. on February 05, 2015, 05:02:21 PM
That looks like a very simple fix to me. Just straighten the transistor and put the tip of the iron right in the corner made by the busted lead and the solder pad and flow some solder to make a good fillet. No problema.
Title: Re: Snapped mje5731ag lead
Post by: spiral2012 on February 05, 2015, 05:57:09 PM
That looks like a very simple fix to me. Just straighten the transistor and put the tip of the iron right in the corner made by the busted lead and the solder pad and flow some solder to make a good fillet. No problema.

Thanks,  Doc!   Would love to hear about the differences between this one and the current speedball from the man himself.
Title: Re: Snapped mje5731ag lead
Post by: Paul Birkeland on February 05, 2015, 06:18:22 PM
Yes, I built this amplifier.  These are incredibly rare and certainly something to hang onto!

If you have any issues getting it working, this does fall under our flat rate repair service, and we'd be happy to take care of it for you.

As Doc B. said, just hit that leg with your soldering iron and you should be OK.

-PB
Title: Re: Snapped mje5731ag lead
Post by: spiral2012 on February 06, 2015, 05:27:05 AM
Yes, I built this amplifier.  These are incredibly rare and certainly something to hang onto!

If you have any issues getting it working, this does fall under our flat rate repair service, and we'd be happy to take care of it for you.

As Doc B. said, just hit that leg with your soldering iron and you should be OK.

-PB

So awesome!  Definitely glad I picked this one up.  Any sonic differences between this and the current speedball?  Thanks!
Title: Re: Snapped mje5731ag lead
Post by: Paul Birkeland on February 06, 2015, 06:30:14 AM
Your Crack uses a different driver tube, which is what sounds different.  Some components on the Speedball are modified to make this work.

-PB