[Heathkit] Dumb speaker question

[rbethman]

Wayne,

You could begin by unsoldering one leg of say 25% of the resistors and 
measuring their value.

Use that result as the basis to determine whether to go for complete 
replacement, OR continue to check another section, and replacing only 
those that are out of tolerance.

Those components dealing directly with IF stages and oscillators will be 
the most productive.

Yes, getting one of these old gals up to snuff isn't trivial or fast.  
Takes a fair amount of time and effort.

You could "try" an alignment first, and see how much that helps.

It is going to be ultimately up to you, but you also don't know whether 
someone "twiddled" adjustments along the way.

Bob - N0DGN

On 2/28/2010 2:53 PM, Wayne Harrah wrote:
> <snip>
>
> An SB-310 or an SB-102 "SHOULD" receive as well as an FT-101 or a
> TS-520.
> An alignment would be beneficial, HOWEVER, you'll most likely also find
> resistors and some capacitors have gone significantly out of spec.
> It will be a dual effort.  I'd suggest first checking component values,
> especially the resistors, before performing an alignment.
>
> <endsnip>
>
> This will sound like its right out of a "Mr. Obvious" script, but need a
> clarification on philosophy in restoring Bas... I learned a long time
> ago from my Elmer that in checking resistances, you have to isolate the
> device being measured from the rest of the circuit... which means there
> is likely a lot of invasive lead-cutting and re-soldering to restore
> connections, is there not?  If so, it seems to me that just going ahead
> and replacing each component might be the smart thing to do.
>
> What is the general concensus on that endeavor?  Is that a wise move
> once one decides to go thru the radio, to just replace every resistor
> and cap? Seems like a daunting job, but at the same time your reply
> makes it sound worthwhile.
>
> Thanks.
> Wayne, ke0ms
>
>
>
>
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