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Bottlehead Kits => Crack => Topic started by: hockeygreen2 on January 02, 2022, 10:01:33 AM

Title: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 02, 2022, 10:01:33 AM
Hi! First time building a kit like this. Assembled it a few days ago, passed the resistance check and voltage check. The amp worked and sounded really great, there was some electronic noise that I noticed that I assumed was due to a few sloppy soldering joints on my part, I tried to fix them up but now I can only get sound out of the left channel, there is no sound out of the right. I went back to basics and re-did the resistance check, all the terminals measure fine except for 6 and 8 which measure above zero ohms now. 6 measures essentially as infinity and 8 measures as 2.9 which I though was extremely strange. In addition to that the second led on a8 does not light up anymore. I've tried re flowing joints, adding solder, taking away solder with my desoldering pump, I've been doing this for the past two days with no luck, needless to say I'm completely stumped. If you guys can help me out I would greatly appreciate it. Let me know if there is any more info, pics, and measurements that you might need to help me figure this out.
Thanks!
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 02, 2022, 10:36:51 AM
Can you post some photos of your build?

Terminals 6 and 10 should have 0 ohms with no headphones plugged in.  If you don't see that, the immediate suspect is the joint on the headphone jack where the black wires meet.

The LED not lighting up on the socket is often a loose joint that has nothing to do with the LED itself.  If you attempt to resolder the LED repeatedly, you'll damage the LED.  Can you post your voltages on terminals 1-10? (after checking the above mentioned solder joint)
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 02, 2022, 11:50:03 AM
Hello! So bad news, when I measured the voltage of terminal 3 there was a big pop and some sparks flew. I tried re soldering the jack where the two black wires meet. Here are some photos of the build.
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 02, 2022, 12:05:37 PM
Here's some more photos.
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 02, 2022, 12:07:07 PM
One more! Sorry for the spam but I'm having some connectivity issues with the forum, doesn't seem to be letting me put all the photos in one post.
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 02, 2022, 12:26:05 PM
There are on or more issues at work here.

1.  You definitely need some proper side cutters.  CHP-170 cutters are inexpensive and do the job well, and this will let you trim your leads back considerably.
2.  Possibly your iron isn't hot enough to properly flow your solder and/or
3.  You're using lead free solder.

Notice that none of this really has anything to do with skill level or experience, so rest assured that some adjustments to tools and temperature settings are likely all that's needed (and maybe a new LED or two).
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 02, 2022, 01:30:08 PM
Hi! So I definitely used lead-free solder for the build. I just ordered some leaded rosin core solder which should be here in a couple of days. I think my plan right now is to try and clean up the board as much as a can with the new solder when it gets here. Fingers crossed the new solder helps solve the issues, once I do this I'll message again if it still does not work. Thanks so much for your help! I hope that the leaded solder will help fix most of these issues!
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Doc B. on January 02, 2022, 01:45:55 PM
We do have a soldering primer now, that might be helpful -

https://youtu.be/EN16Pi7pcfk
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 02, 2022, 03:22:09 PM
You're going to be shocked at how much easier leaded solder is to work with.
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 05, 2022, 09:10:50 AM
Hi! Just got the leaded solder today! You're right it is so much easier to work with. I've resoldered most of the problem connections, and now both terminal 6 and 9 are measuring as 2.9 which is still not right but its different then it was before. just wondering if there is any more connections that you would think still need to be resoldered
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 05, 2022, 09:12:30 AM
Just to be clear, terminals 7 and 9 should measure about 3K.  Are you absolutely certain that terminal 6 measures 2.9K? 

If terminal
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 05, 2022, 09:20:08 AM
Yes. I've measured 6 a few times and it measures at 2.4 now
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 05, 2022, 09:22:02 AM
OK, 2.4 means that you have probably overheated the jack to the point that the plastic has melted and the contacts have moved.  This would not be that surprising knowing that you used lead free solder, since that stuff is so resistant to flowing in the first place that it takes a ton of heat to get satisfactory results.  I would definitely replace the HP jack.
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 05, 2022, 09:33:19 AM
Okay that makes a lot of sense, the headphone jack does look like it's in bad shape, any ideas on where I could get a replacement?
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 05, 2022, 11:52:30 AM
What country are you in?  It would probably be easiest for me to find you one from a retailer near you to avoid international shipping.

-PB
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 05, 2022, 12:16:01 PM
I appreciate it! I'm in the US specifically New York State, near the buffalo area
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 05, 2022, 12:41:38 PM
Ah, I'm not sure why I thought I saw your transformer wired for 240V. 

You can e-mail replacementparts(at)bottlehead(dot)com about getting a replacement jack. 

-PB
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 18, 2022, 01:29:29 PM
Hey guys. So I replaced the headphone jack, and soldered in a new led, all the resistances measure good now. But im still only getting sound out of the left channel. I am completely stumped here.
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 18, 2022, 01:45:22 PM
Can you post your voltages on terminals 1-10 and some photos of the build as it sits now?
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 18, 2022, 02:21:10 PM
So, when I plugged in the amp to measure voltages, I heard a small hiss sound, and I started to smell something, I quickly unplugged the amp, when taking a look at the amp, I got shocked by the capacitor connected to terminal 20 and 21, which I though was extremely strange as there was no power going through the amp when I was inspecting it. Something has gone severely wrong with this it seems. Heres some photos of the build in its current state.
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 18, 2022, 02:26:25 PM
Those diode leads sticking out around terminal 19 (where the red wire goes) need to be trimmed back.

The diode going to A3 looks like possibly it's installed in such a way that the leads coming out of each end of the diode are touching, which would also be a problem.

None of this will make a part hiss.  If your resistance checks are still OK, then I would attempt to measure voltages.
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: hockeygreen2 on January 18, 2022, 02:33:22 PM
Ok, those fixes shouldn't be too bad! Also I am currently feeling some heat coming off the capacitor connected to terminals 20 and 21, I tried to measure the voltage earlier but it sparked, should I be concerned about this/is there a way to get the current out of this capacitor?
Title: Re: Crack resistence check, getting above 0 ohms on terminal 6 and 8
Post by: Paul Birkeland on January 18, 2022, 02:39:38 PM
With the amp off and discharging, if the voltage on the unbanded end of that capacitor is much different than the voltage on the unbanded end of the other 220uF caps, that would suggest a loose 270 ohm resistor or a loose black wire back there that is preventing it from bleeding down properly.