discrete opamp current sources?

Found this discrete audio type opamp from 1977

http://es.geocities.com/mart_in_medina/918opamp.jpg

Question
The designer used two sets of diodes for setting the bias for Q3, Q4

I would normally just use 2 diodes common to Q3, Q4

What's the advantage in using 2 sets of diodes?


martin
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Relevant Pages

  • Re: Telephone : Checking for "RTS"
    ... far as I can see he (the designer) mixed up his zener-diode ... trafo and capacitors etc. ... As far as I can see it those diodes cannot limit anything to 5V, ... Rudy Wieser ...
    (sci.electronics.design)
  • Re: Telephone : Checking for "RTS"
    ... why did the designer de-couple from the Phone-line with a trafo and ... Why did he not just leave-out those capacitors? ... As far as I can see it those diodes *cannot* limit anything to 5V, ... Now I look more closely at it, I must say that that opto-coupler does not ...
    (sci.electronics.design)
  • Re: discrete opamp current sources?
    ... The designer used two sets of diodes for setting the bias for Q3, ... I would normally just use 2 diodes common to Q3, ...
    (sci.electronics.design)
  • Re: discrete opamp current sources?
    ... The designer used two sets of diodes for setting the bias for Q3, ... I would normally just use 2 diodes common to Q3, ...
    (sci.electronics.design)
  • Re: Rf switch using pin diodes
    ... The bias traces don't carry any power to speak of. ... The end of Agilent app note "Application of PIN Diodes" explains power handling capabilities. ...
    (sci.electronics.design)