No grid stoppers on lite 2b pre amp?

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joekelly9692
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No grid stoppers on lite 2b pre amp?

Post by joekelly9692 »

Hey lads. Am I right in saying that there is No grid stoppers on lite 2b preamp?

Is it easy to explain why this is the case. :oops: Joe.
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JMPGuitars
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Re: No grid stoppers on lite 2b pre amp?

Post by JMPGuitars »

No you're correct, and maybe. I recently noticed that too. I'm going to add a 10K grid stopper on the input of my old single-input lite 2b. If you're going to do that, add the resistor directly to the tube, and use shielded wire from the jack (obviously only one side of the shielding gets connected to anything - jack side is easier).
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geoff 1965
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Re: No grid stoppers on lite 2b pre amp?

Post by geoff 1965 »

hello Joe,
the lite2b is a fairly clean preamp so i think that's the main reason for not having grid stoppers,the purpose of the grid stopper is to stop any radio interference etc and if you look at schematics of higher gain amps with cascaded preamps they have them to prevent this and also prevent any oscillation.i did a cascade mod to my lite2 and the increase in gain is massive so i used a 33K grid stopper into the 2nd triode but in parallel i have no grid stoppers and the signal is clean with no intereference.
PREAMP.jpg
saying that! i've seen other lite2 amps with grid stoppers and if you look at the standard 18watt the normal channel does'nt have them but the tremelo channel does! so it's a case of if you're picking up interference then fit them,Josh's advice is good regarding how to and resistor value.
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joekelly9692
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Re: No grid stoppers on lite 2b pre amp?

Post by joekelly9692 »

Awesome info fellas. .. this is all beginning to sink in.. :)
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