[Hammarlund] 180A Concerns & Problems(Long)

[Edward B Richards]

Hi Kim et al;

Some more thoughts:

A properly calibrated digital meter should measure B+ and line voltage
accurately. The only time it will read higher than a 260 is in a high
impedance circuit, then it is the digital meter that is closer to reality
as the internal resistance of the 260 will draw a small amount of current
causing a voltage drop across the high Z circuit

Old filter caps (dried out or leaky) will only lower the voltage. Since
the voltage is too high it indicates excessive line voltage. Even though
it is within tolerance, I would lower it to where B+ is what the manual
calls for. Excessive B+ means more power being consumed that adds extra
heat and stresses other components like the power transformer. Unless you
are prepared to replace the power transformer, lower that voltage.
Thanks.

Ed Richards K6UUZ 

On Mon, 29 Sep 2003 09:01:23 -0400 Kim Herron <kherron@voyager.net>
writes:
> Hi again gang,
> 
> 
> > > 1. ALL the tubes run very very hot, I removed the tube
> > > shields and tuning cap covers
> > > as per addendum.
> > > My house AC is at 121VAC, the 180's 250VDC is at 275VDC, and
> > > the 275VDC is
> > > 300VDC.  Should I run the 180A with a variac at 110VAC??
> > > Will the 180A fail?
> 
>        Something else here that I forgot to mention.  The volt meter 
> that 
> was use to establish the norms
> listed in the manual was a 20,000 ohms/volt meter, probably a 
> Simpson 260.
> If you are using a modern meter (digital 11 megohm input), you'll 
> find that 
> your measured voltage is 10 to 15 percent higher.
> Maybe more. They don't load the circuit like the old VOM's.  A 
> friend 
> called me from Ft. Wayne telling me that his line voltage was at 138 
> VAC.
> The power company came out and checked his voltage and it was at 
> 120VAC.  They used a Simpson 260.  The point is not to let
> your new DVM send you looking for problems that aren't there.  
> You'll see 
> that the voltages mentioned above are in that range.  I'd bet
> that the receiver is just fine, needs caps and a touch up on the 
> alignment.
> 
> 
> Thanks!!
> 
> Kim Herron
> 1-616-677-3706 
> 
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