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Scott
July 13th 03, 11:26 PM
One day (back in 1983) I was listening to a Technics receiver in an
audio store. This particular model was rated at something like 40 or
45 watts per side.

When the receiver was cranked up (and not clipping according to the
power indicators) the bulb that lights up the tuner dial was dimming
(brighter, dimmer, brighter, etc) to the beat of the music.

Was this caused by an inadequete(sp) power supply? I never saw any
other brand of receiver do this except for this cheap Sharp all in one
system I had was I was a kid.

thanks all
Scott

Mark D. Zacharias
July 14th 03, 12:31 PM
Mainly just means it was a DC voltage for the lamps instead of AC. Yes it
was probably lightly (poorly) filtered. Could mean other things I suppose,
like resistive losses in the power transformer, but I would say this is
unlikely.

Mark Z.

"Scott" > wrote in message
m...
> One day (back in 1983) I was listening to a Technics receiver in an
> audio store. This particular model was rated at something like 40 or
> 45 watts per side.
>
> When the receiver was cranked up (and not clipping according to the
> power indicators) the bulb that lights up the tuner dial was dimming
> (brighter, dimmer, brighter, etc) to the beat of the music.
>
> Was this caused by an inadequete(sp) power supply? I never saw any
> other brand of receiver do this except for this cheap Sharp all in one
> system I had was I was a kid.
>
> thanks all
> Scott
>

Nothing40
July 14th 03, 08:33 PM
Hmm,I think it would make me wonder if the power supply is up to par.
That's somewhat normal,to some extent.
Personally I like amps that have Honkin Huge power supplies,ones that
will make the lights in the house dim,instead of the ones in the amp.
;-)

If the amp is rated at 200wpc,and the power supply isn't nearly back
breaking,forget it.Unless,of course if the power supply is a switching
type.
Some will also tell you to run from an amp with a switching supply!
I'd tend to agree..I like the big huge solid linear supplies myself.


(Scott) wrote in message >...
> One day (back in 1983) I was listening to a Technics receiver in an
> audio store. This particular model was rated at something like 40 or
> 45 watts per side.
>
> When the receiver was cranked up (and not clipping according to the
> power indicators) the bulb that lights up the tuner dial was dimming
> (brighter, dimmer, brighter, etc) to the beat of the music.
>
> Was this caused by an inadequete(sp) power supply? I never saw any
> other brand of receiver do this except for this cheap Sharp all in one
> system I had was I was a kid.
>
> thanks all
> Scott

GregS
July 15th 03, 01:57 PM
In article >, (Nothing40) wrote:
>Hmm,I think it would make me wonder if the power supply is up to par.
>That's somewhat normal,to some extent.
>Personally I like amps that have Honkin Huge power supplies,ones that
>will make the lights in the house dim,instead of the ones in the amp.
>;-)
>
>



>> Was this caused by an inadequete(sp) power supply? I never saw any
>> other brand of receiver do this except for this cheap Sharp all in one
>> system I had was I was a kid.

Most receivers do that. Its mostly the transformer chracteristics, line cord, fuse, connections,
and basically how well the transformer can deliver to the amp without affecting
the cores linearity.

greg

Jerry Greenberg
July 17th 03, 04:14 AM
This is a crude way to find out that the supply is a bit weak for the
output stage when under a lot of stress. Infact, it is very hard on
the output stage of any amplifier to drive it near or at the clip
level. This causes it to run very hot, and increases the chance of
failure.

If the power supply gives a little, it will help aleviate some of the
stress to the output stage, even though it causes some less stable
conditions.

In the design, larger main filter capacitors is one way to achieve
peak stability, but for overall continious stability, a larger power
supply design with a higher current output is the best solution.


Jerry Greenberg
http://www.zoom-one.com

--






(Scott) wrote in message >...
> One day (back in 1983) I was listening to a Technics receiver in an
> audio store. This particular model was rated at something like 40 or
> 45 watts per side.
>
> When the receiver was cranked up (and not clipping according to the
> power indicators) the bulb that lights up the tuner dial was dimming
> (brighter, dimmer, brighter, etc) to the beat of the music.
>
> Was this caused by an inadequete(sp) power supply? I never saw any
> other brand of receiver do this except for this cheap Sharp all in one
> system I had was I was a kid.
>
> thanks all
> Scott