In article , Old Fart at Play
wrote:
Jim Lesurf wrote:


In order to put the cat amongst the pidgeon I will admit that I ended
up preferring to use HA12017's as general purpose op-amps for audio
purposes.


I still have a couple of HA12017s and an RS datasheet from 1982.
(Photocopies on request).

I have the Hitachi databook for them.

Are the 12017's still avalable, or are they now obsolete and deleted from
all stocks?

What values did you come up with for compensation for line-level
low-gain circuits?

This has reminded me that the diagram really should be on the Armstrong
site as I used them for the 700 preamp...

10pF from pin 5. 100pF from pin 1.

Join the other ends of the above caps together and to a 1k resistor to
ground.

I also tended to have a 10pF or 20pF across the feedback resistor.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html