Building an Aleph 5...two quick questions

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So here they are:

1) For the 1 ohm (power mosfet source resistors) and 0.47 ohm ( x4 output resistors), is a 5 watt rating for each sufficient?

2) What kind of capacitor is recommended for the 680pf and 10pf caps? Silvered Mica, Ceramic?

Your advice is most appreciated.

Greg.
 
Hi Guys,

I actually am building an Aleph 2 now, but thought I would post this question here rather than start a new thread.

Just wondering if 0.5 watts is a high enough rating for the 9.1v zener diodes used to bias the input current source and protect the input fets from static?

Your advice is appreciated.

Regards,

Greg.
 
Sounds a bit like you bought a 30VAC toroid that gives 30xsqrt(2)=42.3 VDC as output voltage (minus 1.4 V of the recitfier bridge plus the voltage regulation of the toroid).

If so, you can either use the higher voltage to feed your Aleph5 (and lower bias to get power dissipation down, maybe not so nice option) or get a 21 or 22 VAC toroid.

Hannes
 
the toroids do give 2 x 30v and i do whant to use them.
i bought it all together as a set from someone who did not have the time to finish the project.
so if it is possible to use the, then i would like to know how to lower the bias.
i am using the pcb from KK.

you can use your toroids. no problem. the design is for 2x28V transformer.
use a CRC psu and 0.5-1ohm resistors 25W. and your down to ~+/-34V.
 
i bought a nearly complete set from a man here in holland who did not have time for it anymore. it whas with pain in hiss heart he sold the set. only thing i mis is the dale 453 ohm.
the toroids where his choice. tiny problem, but i think i'll be a lucky man when i am finnished.
 
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