Bottlehead Forum

Bottlehead Kits => Stereomour II => Topic started by: benzxc on August 20, 2019, 11:47:11 PM

Title: #8 solder tab
Post by: benzxc on August 20, 2019, 11:47:11 PM
So my kit is missing the #8 solder tab and instead I received three #6 solder tabs. Is it possible to use the #6 solder tab in the place where I am supposed to use the #8?

I checked with two of my local hardware stores and neither of them stocked the solder tabs. Amazon doesn't ship to where I am either. So if it is possible for me to do use what I have, it would save quite some time and hassle!

Thanks,
Ben
Title: Re: #8 solder tab
Post by: Deke609 on August 21, 2019, 03:03:58 AM
Yeah, I've had to use #6 in place of #8 a couple of times. Works fine - there's no magic to the sizing other than #6 can be difficult to get on the threads of a #8 bolt.  What I do is carefully bend one of the star points of the tab up and the next one down, and so on - and then trim the bent points a bit with flush cutters. The only reasons for the alternating up/down is to create some space around the points for the flush cutters.


cheers, Derek
Title: Re: #8 solder tab
Post by: benzxc on August 21, 2019, 03:27:18 AM
Thanks a lot Derek! Going to try that now!

Ben
Title: Re: #8 solder tab
Post by: benzxc on August 21, 2019, 03:48:26 AM
Works perfectly!

Thanks,
Ben
Title: Re: #8 solder tab
Post by: Deke609 on August 21, 2019, 03:51:53 AM
Cheers! Glad it worked. It would be frustrating to halt a build while waiting for a single $0.15 part!
Title: Re: #8 solder tab
Post by: Paul Birkeland on August 21, 2019, 04:45:43 AM
It's also worth mentioning that the outside dimensions of the #6 and #8 solder tabs are about the same, while the only real difference is how long the inner teeth are.  It can be rather difficult to tell them apart visually, and it's super easy to accidentally overlook the #8 solder tab as a #6.
Title: Re: #8 solder tab
Post by: benzxc on August 21, 2019, 05:57:53 AM
Noted, thanks Paul!
Title: Re: #8 solder tab
Post by: benzxc on August 21, 2019, 06:16:43 AM
By the way, any tips for removing the shielded wire and stripping the wires inside? I had a little bit of trouble removing and stripping them by simply cutting the wires. I eventually got it to work by cutting real slowly and there are still quite a bit of shielded wires left since a lot was provided but it would be nice to know if there is a preferred method to do so.

Thanks,
Ben
Title: Re: #8 solder tab
Post by: Paul Birkeland on August 21, 2019, 09:35:18 AM
Is this for the black STP or the CAT5?
Title: Re: #8 solder tab
Post by: benzxc on August 21, 2019, 01:12:58 PM
The black STP
Title: Re: #8 solder tab
Post by: Paul Birkeland on August 21, 2019, 02:02:35 PM
Yes, go slowly when you take off the outer jacket.  One of those hardware store wire strippers that has the row of differently sized strippers can take the black jacket off reliably, and a normal wire stripper for fine wire can be used on the inner solid core wires.
Title: Re: #8 solder tab
Post by: benzxc on August 22, 2019, 03:01:35 AM
Thank you, Paul.
Title: Re: #8 solder tab
Post by: benzxc on August 22, 2019, 04:58:46 PM
I successfully stripped the shielded wires! But when I was stripping the last one required for the build, I accidentally clipped a bit of the drain wire as well. It is not cut through, but there is a noticeable clip where the outer jacket was removed. Is this going to be a problem?

Now that I'm run out of the shielded wires, I hope I don't have to get some more (I assume they can be bought at hardware stores). If it's a problem, would it be ok if I simply pull a bit of the drain wire from the remaining portion of the shielded wire?

I know it's probably hard to troubleshoot this issue without a photo but for some reason my phone camera is acting up and not letting me take a photo. Will upload a photo as soon as I can.

Thanks,
Ben 
Title: Re: #8 solder tab
Post by: benzxc on August 22, 2019, 06:19:59 PM
Here it is. Thanks!
Title: Re: #8 solder tab
Post by: benzxc on August 22, 2019, 07:00:05 PM
From the opposite angle.
Title: Re: #8 solder tab
Post by: Tom-s on August 22, 2019, 07:48:25 PM
I think it still looks ok.
If it feels firm, i'd keep it just like you have.
And if you have some portion of it remaining on the other side of the wire, you could test for continuity.
Title: Re: #8 solder tab
Post by: benzxc on August 22, 2019, 11:06:30 PM
Thanks, Tom!
Title: Re: #8 solder tab
Post by: Deke609 on August 23, 2019, 02:39:24 AM
It looks like you only nicked the outer tinning, so I'd say you are fine. The only purpose of the drain wire is to connect the tinfoil shield wrapped around the larger wire bundle to ground so that any induced currents (interference) in the tinfoil shield can "drain" to ground. We're talking about very small currents. It's not part of the either the signal wiring or the power wiring.


At most I'd guess that the nick in the drain wire has reduced the amount of mechanical stress (e.g., repeated bending) that the wire can take. But that's not an issue b/c it won't be subjected to mechanical stress.


[And I'll add: this is coming from someone (me) who is obsessed with shielding and drain wires - I add copper shielding to pretty much every wire I can and am pretty fussy about it. And that nick in the drain wire wouldn't bother me  ;) ]


cheers, Derek
Title: Re: #8 solder tab
Post by: Paul Birkeland on August 23, 2019, 05:05:42 AM
I would be more concerned about the two 4-40 nuts on that screw mounting the terminal strip.
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 05:16:43 AM
Derek,

Thanks a lot!  Great information to know!

Paul,

Thanks!  Just to double check - I just went over the manual and on page 15 it states that I was supposed to mount two #4 nuts on the terminal strip.  Did I do something wrong there? 

Ben
Title: Re: #8 solder tab
Post by: Paul Birkeland on August 23, 2019, 06:25:50 AM
Ah, it looked a little funny, but now I am indeed remembering that the standoffs are uneven without it!  Sorry to bug you about that.
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 06:40:36 AM
Phew!  For a second there I thought I had to take apart my build!  Good to know that is not necessary! 8)
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 09:19:15 AM
Just did the resistance check - all good.

Voltage check - all good except for terminal 17, which is supposed to be 0V, I am getting 15-25v.  Any ideas?

Thanks!
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 09:25:22 AM
An LED just exploded!
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 09:35:09 AM
Two popped I think.  Going to need to order replacements, but will turn it off for now until I figure out what's wrong with it.
Title: Re: #8 solder tab
Post by: Deke609 on August 23, 2019, 09:42:03 AM
You'll need PB to diagnose this, but to get the ball rolling I suggest you post pics of the pcb board, the terminal strip with T17 and the D 4-pin socket.
Title: Re: #8 solder tab
Post by: Paul Birkeland on August 23, 2019, 09:44:21 AM
Voltage check - all good except for terminal 17, which is supposed to be 0V, I am getting 15-25v.  Any ideas?
There's a 249K resistor from 17 to 16, then a black wire from 16 to ground.  One of these is probably not connected.

Posting photos would be a good idea.

LEDs explode when there's an electrically egregious miswire (usually).
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 09:49:32 AM
Here are the photos
Title: Re: #8 solder tab
Post by: Paul Birkeland on August 23, 2019, 09:56:05 AM
Ah, so the half of the C4S that feeds the side with the problematic voltage is OK.

It would be good to see the other 4 pin and 9 pin socket where that half of the C4S board feeds.
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 10:01:58 AM
Somehow I am having difficulty uploading pictures. Will do so later. Thanks for all your help!

The explosion might have gotten me banned from experimenting with DIY at home for a while....

PB, do you have an idea as to how long repair might take, if I decide to send it for repair?

Thanks!
Ben
Title: Re: #8 solder tab
Post by: Paul Birkeland on August 23, 2019, 10:09:50 AM
My bench is pretty jammed right now, as a bunch of repairs rolled in almost all at once, but they should be clear in a week or so.
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 10:11:10 AM
Thanks!
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 06:18:05 PM
Here are some photos. Thanks!
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 06:18:47 PM
More.
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 06:19:47 PM
Continued
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 06:20:23 PM
More.
Title: Re: #8 solder tab
Post by: Paul Birkeland on August 23, 2019, 08:03:28 PM
 I see a lot of little pointy bits sticking out that need to be trimmed.  It's quite possible two of them are touching (the one I noticed most quickly was around terminals 6 and 7).

When I see something like this, it is nearly always because the wire cutters used weren't side cutters, so it just ends up being really difficult to get in and trim things up properly. 

-PB
Title: Re: #8 solder tab
Post by: benzxc on August 23, 2019, 08:42:04 PM
Thanks!
Title: Re: #8 solder tab
Post by: Doc B. on September 06, 2019, 10:04:22 AM
I see a lot of cold joints. The red wire connecting to the 4 pin socket is an example. I'd suggest reflowing your joints with a little more solder. Make sure the solder flows into the joint and creates a fillet between the wire and the terminal.
Title: Re: #8 solder tab
Post by: benzxc on September 11, 2019, 06:38:12 AM
Thanks, Doc! Although I would have loved to continue to work on the Stereomour until the problem is fixed, I have decided to send it in for repair. The explosion of the LED, while minor, caused some concern among the household so that is the way we decided to resolve the issue. Living with others is all about compromise!

Ben