[Hallicrafters] SR-2000 post production change

[Carl]

Thanks Jim, now I understand having not owned a SR-2000. But have 
repaired many amps with crystalized solder.

Sorry about the confusion.

Carl



----- Original Message ----- 
From: "Jim Liles" <james.liles at comcast.net>
To: <hallicrafters at mailman.qth.net>
Sent: Thursday, January 29, 2009 2:51 PM
Subject: Re: [Hallicrafters] SR-2000 post production change


> Hi Carl:
> Thanks for your response.  This problem is not a lead tin 
> crystallization
> problem.  It is a cross section problem where a variable cap tab 
> connector
> is far too small.  We simply quadrupled the cross section area of the 
> tab
> and  the heating ceased to occure.  It was heating of the inadequate 
> joint
> that melted the solder.  The cap has three gangs and only one exhibits 
> the
> malady.  We used silver solder to restore the connections for added
> insurance.  What I probably did not convey is that if you have an 
> SR-2000,
> it will absolutely have this problem to some degree.  Kindest regards 
> Jim
> K9AXN
>
>
>
> ----- Original Message ----- 
> From: "Carl" <km1h at jeremy.mv.com>
> To: "Jim Liles" <james.liles at comcast.net>; 
> <hallicrafters at mailman.qth.net>
> Sent: Thursday, January 29, 2009 1:12 PM
> Subject: Re: [Hallicrafters] SR-2000 post production change
>
>
>> Any high power amp will crystalize standard Tin-Lead solder over 
>> time;
>> Hallicrafters is not unique. Solder has a finite amount of resistance 
>> to
>> RF.  The simple cure is to remove all of the solder and flow in new 
>> and
>> dont worry for another 10-20 years. Or use real silver solder.
>>
>> Carl
>> KM1H
>
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