U47xfet PCB from UTM / IGS?

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i have seen it, but how do i know whether a capacitor is a film capacitor or not....
I'm just referencing the pcb to see which are polarized or not, and also checking some of the photos at the beginning of this thread. There's 3 styrene caps, one should've came with the kit, the other two I ordered from Banzai, along with the 2sk117.
SKU21152Styroflex 100pF
SKU273972SK117
 
I'm going to give this build a go and have ordered a UTM47LB kit and a UTM0547f transformer from UTM.
The hardest part is deciphering the BOM and sourcing the components. Its like trying to solving the da Vinci code.
Doesn't help when TimGs Mouser BOM is only 50% complete.
Anyway I got the Mouser BOM and hunting down the rest. Nothing like the thrill of the hunt.
The only thing I have to go off is the schematics and the build picture which are a bit ambiguous.
I sent Igor from UTM an email asking him for clarification of some of the caps used as there has been some confusion as to what type they were.

This is what he said.
C2, C3 - styroflex or ceramic
C4, C9 - WIMA or similar
C6 - Tantal (0.33uF)

C2, C3 I think I can get 18p and 33p Polystyrene caps, just waiting on conformation on stock. If not Ceramics it is.
C4, C9 WIMA caps are easy to get but I might go MKTs.
C6 He said tantalum but I can only get them in 35V. Would they work? If not an Electrolytic it is.

C10 Elna caps are high quality Japanese caps and are easy to get. Should use them for all Electrolytics.

Anyway I hope I've got things right.
 
I'm going to give this build a go and have ordered a UTM47LB kit and a UTM0547f transformer from UTM.
The hardest part is deciphering the BOM and sourcing the components. Its like trying to solving the da Vinci code.
Doesn't help when TimGs Mouser BOM is only 50% complete.
Anyway I got the Mouser BOM and hunting down the rest. Nothing like the thrill of the hunt.
The only thing I have to go off is the schematics and the build picture which are a bit ambiguous.
I sent Igor from UTM an email asking him for clarification of some of the caps used as there has been some confusion as to what type they were.

This is what he said.
C2, C3 - styroflex or ceramic
C4, C9 - WIMA or similar
C6 - Tantal (0.33uF)

C2, C3 I think I can get 18p and 33p Polystyrene caps, just waiting on conformation on stock. If not Ceramics it is.
C6 He said tantalum but I can only get them in 35V. Would they work? If not an Electrolytic it is.
What's similar to a WIMA cap?

C10 Elna caps are high quality Japanese caps and are easy to get. Should use them for all Electrolytics.

Anyway I hope I've got things right.
 
If not Ceramics it is.

Aim for C0G / NP0 - values so low will more likely than not be those materials by default, but you'll wanna make sure.

C6 He said tantalum but I can only get them in 35V. Would they work? If not an Electrolytic it is.

I'd stick with known-brand Japanese electrolytics - Panasonic, Nichicon, Rubycon, Elna, United Chemi-Con.

C10 Elna caps are high quality Japanese caps and are easy to get. Should use them for all Electrolytics.

See above.

What's similar to a WIMA cap?

Film capacitors (PET, PP) - you'll be hard-pressed to hear any differences between the same value but different materials. Well, outside of deluding yourself, that is...
 
Are you guys using 550 and 560 "B" or "C" transistors? I read that the C have a higher gain rating. Not sure if this is a good thing or bad. Thanks!
I used BC550B and BC560B with hfe between 300..400 in similar schemes. They are closer to BC182B and BC212B from the original scheme. I paired T5 and T6.
 

Attachments

  • U47FET-schematic.png
    U47FET-schematic.png
    106.7 KB
  • utm47fsch.pdf
    159.5 KB
  • BC182B Fairchild.PDF
    33.9 KB
  • BC550Fairchild.PDF
    55.7 KB

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