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Tagged: The Vibe
- This topic has 28 replies, 3 voices, and was last updated 2 months, 1 week ago by
Ben Ji.
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December 30, 2025 at 3:57 pm #38142
Ben Ji
ParticipantRegarding Q5 2N4125, i have tested a few from the bag i have (x10) i didn’t touch the one on the board.
I used the FNIRSI LCR-P1 which provides:
– DC current gain -> hfe,
– base-emitter voltage drop -> Ube,
– Ic/Ie, collector-emit-ter reverse cutoff current -> IceHere are the values for 3 FET i took from this bag (new), i’m not sure these value matches the datasheet. What do you think? It is difficult to say because there are so many values.


December 30, 2025 at 4:03 pm #38143Ben Ji
Participantthe speed pot affects voltage on Pin2 up or down a bit if i turn it clockwise or counterclockwise but does not oscillate ‘alone”. Pin6 voltage does not change when i turn the speed pot
December 31, 2025 at 3:35 am #38145
BillyModeratorDoes pin 6 voltage still oscillate regardless of the speed pot
It should if pin 2 oscillates
Try reflowing C8 solder joints
I’ve got a phase 90 circuit somewhere I’ll try to find it and confirm voltages etc unfortunately I had to empty my workshop to get some work done to my house recently so hopefully I’ll find it easily enough
January 1, 2026 at 1:54 pm #38150Ben Ji
Participant- Pin6 clearly does not oscillate
- I tried reflew C8 solder joints
What do you think about the JFET values i gave ? does it look good to you?
January 1, 2026 at 6:50 pm #38151
BillyModeratorThose look like pnp transistors not jfets
January 2, 2026 at 3:38 am #38152Ben Ji
Participanti agree.. i need to source proper ones. this pedal will not work with this PNP. thanks!
January 2, 2026 at 4:29 am #38153
BillyModeratorIt should work OK with any pnp transistor and your matched set of jfets if the LFO isn’t oscillating that’s your problem I’d check all components in that section
I’ve had solder joints that looked perfect but where dry inside not often but you never know
January 5, 2026 at 11:55 am #38171Ben Ji
ParticipantOK i’ll try to reflow a few of these around and let you know how it goes. thanks a lot
January 17, 2026 at 9:41 am #38225Ben Ji
Participanti reflew around C8 , R22/24/25 + IC3 socket. no progress
January 20, 2026 at 11:04 am #38233
BillyModeratorCheck you’ve got a good connection to G2 I’d personally have wired it direct to the DC jack
Remove IC3 from its socket and let us know the voltages on the socket
January 24, 2026 at 11:32 am #38239Ben Ji
Participant<span style=”-webkit-tap-highlight-color: rgba(0, 0, 0, 0);”>g2 is very well grounded i have verified it is connected to the jack and from the jack i go to another ground.</span>
with no IC3 we have
L2: 2,5/2,3v
L3: 3,7/3,8v
L6: 2,8v
L7: 8,9vall other Lugs are 0v
January 24, 2026 at 11:54 am #38240Ben Ji
Participantis this what you call oscillate ? this is Lug 6 after i replaced IC3 with a more trustworthy supplier. did not test the pedal yet but i can tell you i never had this on this Lug

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