Let's discuss ZM's Good Gemini shunt

Thank you both. It ain't pretty, but I 'hacked' it and added the two resistors.

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D5 and T2 were toast. Also replaced Q2 and JFET2 for good measure/conscience.

So far so good. +/-30V without red-hot heatsinks.

Fun 🙂
 
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I am on my way down another rabbit hole, trying different PSUs for the D1 IV.

Looking at the schematic of Shunty (and uBib), there is what I interpret as 220u across the outputs, but this is not seen on the GG. Could I ask what is behind this difference? It is entirely possible I missed something ... as usual 😆

Happy Saturday -
 
Thank you ZM. I hope I am not stressing your patience too far.

In Shunty this cap is 220uF with 0.22uF across, in GG it is 470uF/1uF. Are these picked based on experience, simulation, anticipated load, or other? I am not going to rush out and by new caps but am curious to understand the difference and/or how one would size these.
 
The story continues.

I have added CRC filtering before the GGs in my DAC and Pre amp. To do this, I removed D1-D4 and then feed the filtered DC to the GG. I think it makes a subtle difference, but then, my expectations are a little biased.

The CRC basically looks like this (curtesy of @miro1360) and the GG has D1 and D4 'shorted. My question is whether there is benefit from adding a resistor in place of shorting D1 and D4 on GG when feeding it from this filter.

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Got a little space management on my hands, or a separate PSU chassis coming up.

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Happy Saturday.
 
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so lets just copy paste what I replied in PM, then harassed you to keep thingies public :rofl:

****************

you can shave 1V max

so, calc - 1V/GG programmed current

calc dissipation on resistor then take triple

P=I^2 * R

say 100ma

1V/100mA=10R

P=100ma^2 * 10=100mW

either use 600mW metal film or use 1w (any sort)

more than triple, in this case, knowing from practice - 600mW (usual 0207 size) are prone to burn if there are any bigger caps to fill during powering up

if having no bugger caps than 470uF, 600mW will suffice for long
 
Thanks ZM. No Danes were harassed in this episode 🙂

Got the resistors in CRC sorted out - at 9R. So, currently, there is 16g solid core between CRC and GG. Basically feeding filtered DC into C1 of GG. Would there be any benefits to a series resistor between CRC and the C1 of GG, basically in the spots of D1 and D4 of GG. Almost CRCRC.

Be patient... Formulating these questions is challenging for me.