joew wrote:
I'm not sure I'm doing this correctly but here is what I did to check the transistor.
Pedal Off:
E-27.2 Ohms
B-0
C-0
Pedal on (same reading with the switch in both env/man
E-9.31v
B-0
C-0
A couple of comments here:
1) Why is your "Pedal off" emitter result reported as ohms?? Looking for DC voltage here.
2) When the pedal is in bypass, the power to the circuit is
still on, as long as your power source is connected and there's a cable inserted into the input jack. The footswitch is
not an on/off power switch; it just switches the effect circuit in and out of the signal path between your guitar and amp/output device.
3) Ignoring the ohms/volts confusion, the results still aren't right. For the transistor in my fully functional EF/FW:
C = 9.95V (same as my power source, to which it is directly connected in the circuit)
B = 1.26V
E = 0.84V
These values are constants withing a couple of hundredths of a volt whether or not the pedal is engaged or bypassed, auto or manual.
You need to get these transistor voltages sorted out before worrying about the 13600. The correct procedure for measuring the transistor voltages is as follows:
Set your multimeter to the DC voltage mode; use the 20VDC range setting if it's not an auto-ranging meter. Of course, your power source needs to be connected and there needs to be a cable in the input jack. If the pedal is assembled into the metal enclosure, put the black probe into one of the corner screw bosses of the enclosure--this is your ground connection. If the "guts" are out of the enclosure, use the sleeve tab of the input jack for the ground connection. Then touch the red probe to the test point that you want to measure and hold it there until the reading is stable within a couple of hundredths of a volt. Repeat the process for each leg of the transistor.
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