Mpp

[hesener]

Originally Posted by Joachim Gerhard

Hesener, C5 should be 1uF printed on the PCB and not 100nF i think, i also can not find the 1MOhm resistor from output to servo.

noted, thanks
the 1M is upper righthand corner, between bc337 and 6.8nf caps

[hesener]

Originally Posted by Joachim Gerhard

What is the big, single 15kOhm resistor in the middle of the PCB, left of the RIAA ?

thats R19, where michael said to let space for a bigger resistor due to higher power dissipation

[Joachim Gerhard]

"She blinded me by science" Thomas Dolby
I already stuffed it !

[TheShaman]

Try Pana FR as well while you're ordering.

[Joachim Gerhard]

It is under the 15 Ohm resistor.

[Joachim Gerhard]

Why ?

[FdW]

Originally Posted by Joachim Gerhard

Why ?

Most probably for thermal constraint, automotive design normally would be for -50C to +100C many (many many ...) cycles. Internal bounds, lead bounds and material tolerance could be at risk.

(that is where I come from )

[Audiofanatic]

Well well, we can shake hands than buddy

Likewise here and agree fully with you.


Audiofanatic

[hesener]

boards are full - power up planned for monday ;-)

this is with LCR caps, Dale resistors, and as good a matching as I could get. Input transistors are matched to 0.7% between all of them, the rest less... Its probably required to order 200...300pcs of each transistor type to get a perfect matching.....

[FdW]

Originally Posted by Audiofanatic

Well well, we can shake hands than buddy

Likewise here and agree fully with you.


Audiofanatic

Cool, and I can be a bit more specific on that. Once (a long time ago) I worked for Motorola, HP and International Rectifier (among others) as an industrial 'components in-design specialist', working with our customers helping with their designs (at the customer’s site) mostly do select components to fit them to their specific environment. I have done planes, trains and automobiles (among others, including the particle accelerator in Cern ).