TROUBLESHOOTING GUIDE
WON’T TURN ON
1. Make sure AC cord is securely connected at both ends.
2. Verify the power source with something you know works.
3. Check the mains fuse, and replace if necessary (if it blows again, refer to qualified service personnel).
NO SOUND
(One or both channels):
1. Check volume controls.
2. Make sure that the input sensitivity switch is in the proper position.
3. Check the standby switch.
4. Check input cables.
5. Make sure that the mode switch is fully engaged in either pentode or triode mode.
6. Check speaker cables to see if they are disconnected or shorted.
7. Make sure that the impedance selector is fully engaged in its detent.
8. Check for blown speakers.
9. If a channel’s fuse is blown, replace with a 1A fast-blo (if it blows again, refer to qualified service personnel).
RUNNING HOT
1. Set the fan speed to “Hi.”
2. Make sure that the unit has adequate ventilation.
3. Make sure that the fan cord is securely connected.
4. The tubes may be under-biased (refer to qualified service personnel).
DISTORTION
1. Check the speakers.
2. Check the cables. See Installation & Operation
3. Check the impedance setting.
4. Check the signal level at other devices in the signal path.
5. The tubes may be over-biased (refer to qualified service personnel).
11
CONNECTING TO A GUITAR AMPLIFIER
E
ver wonder what that treasured old tweed Deluxe would sound like as a 200-watt powerhouse?
Here’s a simple load box/output pad configuration that will allow you to drag all your favorite antiques
out of the closet and really go for a spin. Just connect the speaker output from your source amplifier to
the input of this load box, and then connect the variable line output of the load box to the A/Mono input of
your 2150 or Classic.
PARTS
LIST
J1, J2 Mono 1/4" phone jack
S1 SPST (single-pole/single-throw) heavy-duty toggle switch
R1 4, 8, or 16 ohm, 100-watt resistor (Dale NH 100 or equivalent)
R2 2,200 ohm, 1/2-watt resistor
R3 470 ohm, 1/2-watt resistor
VR1 10k ohm audio-taper potentiometer
Input
(J1)
S1*
Variable
Line
Output
(J2)
R1**
R2
R3 VR1
* S1 must be closed when no speaker
is connected to amplifier.
** R1’s value will be determined by the
source amplifier’s impedance rating.
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