47 ohm tail resistor

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Mikante
Posts: 200
Joined: Fri Oct 29, 2021 7:07 pm
Location: Italy

47 ohm tail resistor

Post by Mikante »

Guys,
Talking about the 47 ohm resistor after the cathode bypass resistor and cap of the second gain stage of the preamp tube, right where the NF goes back from the output transformer.
I had this resistor on my silver face style champ removed by accident, i just didn t noticed it in the schematic :roll:
I have put it back and find out that now, the cathode bypass capacitor 3way switch selector the i installed as a mod is completely useless.
From 20uf to 0,47uf it makes no difference at all. Also the negative feedback seem to have a lot less impact, why is that?
It is all wired correctly.
3C786035-6260-47BE-8FB2-9A4098142FC5.jpeg
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maxkracht
Posts: 595
Joined: Tue Dec 10, 2019 7:18 pm
Location: Iowa, USA

Re: 47 ohm tail resistor

Post by maxkracht »

If it was all wired correctly it would work. Maybe you are accidentally bypassing the 47r resistor instead of the 1k5?
Mikante
Posts: 200
Joined: Fri Oct 29, 2021 7:07 pm
Location: Italy

Re: 47 ohm tail resistor

Post by Mikante »

sorry for the almost useless post, but I really thought I had everything checked. The wire going to the 3way switch was connected after the 1.5k and so I had the 47 ohm and capacitor in parallel.
maxkracht
Posts: 595
Joined: Tue Dec 10, 2019 7:18 pm
Location: Iowa, USA

Re: 47 ohm tail resistor

Post by maxkracht »

Glad you got it figured out.
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