100 Watt Marshall 2203 Slave Amp Build

ivan H said:
Good to see you've started on the slave amp.
Regarding the band denoting the capacitors outer foil, with Sozo caps you can be pretty well certain that it is oriented correctly, I've never found one that isn't & would be interested to hear if you do.
So which way should the cap be oriented in a circuit??? The outer foil should be oriented toward the lower impedance side of the circuit the cap is placed in. So generally, when decoupling your common pre-amp gain stages (voltage amplifiers), which includes the PI, the outter foil band will go toward the plate of the valve being decoupled. In these cases the DC plate voltage acts to shield the cap, just like using ground.
When it comes to cathode follower driven tone stack's things get a little fuzzy. Which side of the circuit is of lower impedance can be dependant on how the tone controls are set. As such we see people orient them either way in this application. Any other type circuit, outter foil to the lower impedance side of the circuit. Hope this helps. Cheers
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Another example is the bypass caps on the cathode resistors. The outer foil lead should go to ground.

2203 stock.JPG
 
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I hate getting old. I can plainly see the direction markings on the caps of Sysco's above post. I am working of a printed version of the same layout. Can't see a damn thing. Have to hold it up to outside light to read resistor values. Meh..
 
Cadorman said:
I hate getting old. I can plainly see the direction markings on the caps of Sysco's above post. I am working of a printed version of the same layout. Can't see a damn thing. Have to hold it up to outside light to read resistor values. Meh..
Click to expand...

This type thing has been fighting me too, Cador. Lighted Magnifying visor has been my friend for a few years now while soldering etc.
 
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