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Arny Krueger Arny Krueger is offline
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Default ONE repair in all my years...


"ScottW" wrote in message
oups.com...
On Oct 18, 3:05 pm, "Trevor Wilson"


**Arny is acting like an idiot, for reasons best known only to him. The
AVR485


http://www.hifiengine.com/download_c...85_service.pdf

has numerous OP amps which are decoupled, using electros. These are
some of them:


IC781, IC782, IC783, IC784


Actually, the 7 op amps in this part of the schematic are named IC781A,
IC781B... ...IC784A.

VCC+ and VCC- for the entire group of op amps are decoupled by R791 and R792
100 ohm resistors in series with C791 and C792 47 uF/25v electrolytics,
other ends grounded.

But we were talking about power for individual op amps. Each op amp's VCC+
and VCC- line is bypassed to ground by 47 NF (0.047 uF) type Z ceramics.
There is no decoupling for individual op amps. There are no individual
electrolytic capacitors for each op amp.

Well.....I looked at them and they appear to be bypassed with ceramics
(as I noted above)


Agreed.

and all decoupled with a common electrolytic and a resistor
per the definition Arny provided.


Agreed.