EF86 Modern Classic tones

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AleS
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Re: EF86 Modern Classic tones

Post by AleS »

Bieworm wrote:
Sat 01/14/23 8:00 am
With the stupid MV on 10 you won’t hear it’s there. But use shielded wires to implement it.
Will keep that in mind. Am I right in assuming the ground to which the PT grid ref resistors connect to would be an appropriate place to connect the shield?
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JMPGuitars
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Re: EF86 Modern Classic tones

Post by JMPGuitars »

AleS wrote:
Sat 01/14/23 5:33 pm
Bieworm wrote:
Sat 01/14/23 8:00 am
With the stupid MV on 10 you won’t hear it’s there. But use shielded wires to implement it.
Will keep that in mind. Am I right in assuming the ground to which the PT grid ref resistors connect to would be an appropriate place to connect the shield?
No, connect the shield to the back of the pot.
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Bieworm
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Re: EF86 Modern Classic tones

Post by Bieworm »

JMPGuitars wrote:
Sat 01/14/23 6:31 pm
AleS wrote:
Sat 01/14/23 5:33 pm
Bieworm wrote:
Sat 01/14/23 8:00 am
With the stupid MV on 10 you won’t hear it’s there. But use shielded wires to implement it.
Will keep that in mind. Am I right in assuming the ground to which the PT grid ref resistors connect to would be an appropriate place to connect the shield?
No, connect the shield to the back of the pot.
+1 on that! I always do this. But for best results in not ruining your pots you should follow this procedure:
1. Turn pot fully clockwise. In case you burn the carbon strip it’s only on the far end side, where the wiper almost never comes.
2. Sand the back of the pot with a rough grid paper
3. Apply a drop of solder on the back of the pot
4. Solder the shield to that spot while holding it down with a needle nose plier or flat head screwdriver. This helps to do it in one (short) time, to avoid overheating the pot.
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AleS
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Re: EF86 Modern Classic tones

Post by AleS »

More thank you's to both :)

Currently comparing values and voltages and a bit puzzled looking at this TC15 schematic from Trinity: https://www.trinityamps.com/wp-content/ ... tic-v9.pdf

Checking voltages at the EL84s, this reads 242V at the control grid and 384V at the plate - is this a typo and should assume g2 is probably 342?
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JMPGuitars
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Re: EF86 Modern Classic tones

Post by JMPGuitars »

AleS wrote:
Sun 01/15/23 1:55 pm
More thank you's to both :)

Currently comparing values and voltages and a bit puzzled looking at this TC15 schematic from Trinity: https://www.trinityamps.com/wp-content/ ... tic-v9.pdf

Checking voltages at the EL84s, this reads 242V at the control grid and 384V at the plate - is this a typo and should assume g2 is probably 342?
You're reading it wrong. That says 242V at SCREEN grid, and 384V at plate. Plate voltage should be higher than screen voltage, but that's a lot bigger difference than I normally see. Not that there's anything wrong with that, if that's their goal, there may be a reason or sound they like. 🤷
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