Bottlehead Forum

Bottlehead Kits => Stereomour II => Topic started by: Sugar Man on September 17, 2015, 09:26:06 AM

Title: Resistance Check for No. 28 [resolved]
Post by: Sugar Man on September 17, 2015, 09:26:06 AM
The manual says 0.  I'm reading .433 Kohms.  Everything else checked out fine.  On 28L there is a resistor from B5 and a drain wire.  Nothing on 28U.
Title: Re: Resistance Check for No. 28
Post by: fullheadofnothing on September 17, 2015, 09:44:13 AM
Did you paint your chassis?
Title: Re: Resistance Check for No. 28
Post by: Sugar Man on September 17, 2015, 10:30:25 AM
Yes.  Powder coated top and bottom.
Title: Re: Resistance Check for No. 28
Post by: fullheadofnothing on September 17, 2015, 10:56:06 AM
The terminal strip is supposed to be grounded to the chassis. Your paint is insulating it and needs to be scrapped off. This applies to any central terminal of a terminal strip with any connections. All places with bare metal against the chassis are assumed to be electrically connected to the chassis and it is important to confirm that they are.
Title: Re: Resistance Check for No. 28
Post by: Sugar Man on September 17, 2015, 11:37:04 AM
Well that is a substantial problem as the build is complete and the powder coating is not coming off very easily at all.  Is there a work around I can do?  Would I have to then do this to 13, 18 & 28? And the No. 8 screw/solder tab by the power cord?  Anywhere else? Can I scrape off the paint next to those areas and solder the terminal base to the bare metal?  Thanks.
Title: Re: Resistance Check for No. 28
Post by: Paul Birkeland on September 17, 2015, 11:44:19 AM
  Is there a work around I can do?
No, anything you do to "simulate" these connections may present a safety hazard or create a noise problem.  It isn't impossible to remove the screws in the pertinent areas, then scrape underneath them with a chisel or small knife.

Would I have to then do this to 13, 18 & 28? And the No. 8 screw/solder tab by the power cord?
Yes.

Anywhere else?
I don't believe so.

Can I scrape off the paint next to those areas and solder the terminal base to the bare metal? 
Soldering to aluminum is very, very difficult to do.  You have to deal with the oxide layer and you have to use a solder without tin in it.  In addition to this, when you get the plate hot enough to actually get a joint, you'll burn the powder coating right off on the other side of the panel. 
Title: Re: Resistance Check for No. 28
Post by: Sugar Man on September 17, 2015, 11:57:34 AM
Well, it looks like a-scrapin' I will go.  Thanks for the quick replies.
Title: Re: Resistance Check for No. 28 [resolved]
Post by: Sugar Man on September 17, 2015, 02:07:30 PM
Okay, all 0's are 0's now except for 33 and 43 which read O.F.  Neither of these has anything hooked up to them so I did not scrape off paint there.  47 and 48 also read O.F.  I'll wait to voltage check until I get the go ahead that these numbers are kosher, especially since my 10 year old just played the packet of gum that shocks you trick on me.
Title: Re: Resistance Check for No. 28 [resolved]
Post by: Paul Birkeland on September 18, 2015, 12:24:28 PM
Okay, all 0's are 0's now except for 33 and 43 which read O.F.  Neither of these has anything hooked up to them so I did not scrape off paint there. 
No worries there.
47 and 48 also read O.F.  I'll wait to voltage check until I get the go ahead that these numbers are kosher, especially since my 10 year old just played the packet of gum that shocks you trick on me.
Your readings are consistent with what's in the manual.
Title: Re: Resistance Check for No. 28 [resolved]
Post by: Sugar Man on September 20, 2015, 04:56:57 AM
Thanks, PB.  With the go ahead I plugged her in and all the voltage tests were spot on, so another Stereomour II is up and running, dead silent and singing!  Wow!!!  :o
Title: Re: Resistance Check for No. 28 [resolved]
Post by: Paul Birkeland on September 20, 2015, 03:50:40 PM
I like the color choice for the top plate!