Michael Landau amp resistor identification?

[FuzzFaceBuilder]

Hey all,

I’m looking at this 50 W once owned by Michael Landau. Can you guys help me identify the cathode value of the first stage? I’m reading it as 2.74K. Red-violet-yellow-brown-brown-red. Though the violet band is hard to see on the blue casing.

Even at that, the Rp-Rk ratio is 1/18.5, 100K/5K4!

What do you guys see?

Thanks!

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[martin manning]

I agree.

[FuzzFaceBuilder]

Martin,

Thanks for the confirmation!

[Matthews Guitars]

When the fourth band is red, it indicates 2 percent tolerance. This would replace the gold (5 percent) or silver (10 percent) tolerance band.

If there is a fifth band and it is yellow, that is a mil-spec marking indicating the established reliability category of the resistor.

[sluckey]

When the fourth band is red, it indicates 2 percent tolerance. This would replace the gold (5 percent) or silver (10 percent) tolerance band.

If there is a fifth band and it is yellow, that is a mil-spec marking indicating the established reliability category of the resistor.

That's not true for this 6 band resistor. The first three bands are just numbers. The fourth band is the multiplier. The fifth band is the tolerance. And the sixth band is reliability.

So this red-vio-yel-brn-brn-red is 2740Ω 1% 50PPM

https://www.digikey.com/en/resources/co ... color-code

[Matthews Guitars]

I was thinking more of four band color codes. Obviously there are several color codes and even though I started learning electronics, beginning with resistor color codes, 46 years ago, there are times when I still have to refer to a cheat sheet. "Is that a mil spec high reliability resistor or a precision resistor with more significant digits? " Such as a 234.1K 1 percent resistor...which code series would you expect that to be?

It can still be confusing.

[sluckey]

Such as a 234.1K 1 percent resistor...which code series would you expect that to be?

Have you actually seen this resistor or did you just make up that value? If it exists it would probably make more sense to stamp the numbers on the resistor rather than use a color code.

[wpaulvogel]

It’s not going to get close to cold clipping. You’re only going to put about 100mV on the grid and even if you boosted the heck out of it, V1 has the last chance of clipping. It usually has an OUTPUT VOLTAGE swing of only 5volts. The 2.7k is to reduce gain.