General Description
The WA301 is a DC to 1MHz amplifier with a maximum output (e.m.f.) of 30 Volts peak to peak
from a 50Ω source impedance. A 600Ω output is also provided. The unit can provide up to 15 Volts
peak to peak into a 50Ω load and can drive up to 300mA peak into a low impedance or short circuit.
Fully variable gain between x1 and x10 is provided by a rotary vernier with calibrated end stops.
A -20dB output attenuator is also incorporated. An "OUTPUT CLIP" lamp is provided to warn if the
output amplitude exceeds ±15V.
Power
When the AC power is connected the amplifier is on and the front panel POWER lamp is lit.
Disconnect from the AC supply by unplugging the mains cord from the back of the instrument or by
switching off at the AC supply outlet; make sure that the means of disconnection is readily
accessible. Disconnect from the AC supply when not in use.
Operation
Connect the signal to be amplified to the socket marked INPUT and the load to the appropriate
output. Note that the 50Ω and 600Ω outputs are not independent (the 600Ω OUTPUT is derived
from the 50Ω OUTPUT via a 550Ω resistor) and loading one will affect the other. Adjust the input
signal level and/or the vernier GAIN control to set the required output signal amplitude. The end
positions of the GAIN vernier are calibrated to be x1 and x10. The OUTPUT CLIP lamp will light if
an attempt is made to set the output level to greater than ±15V.
A -20dB output attenuator can be selected; this usefully extends the output amplitude range when
working with a fixed level input signal. The ATTENUATION lamp is lit when the -20dB attenuator is
selected. The amplifier output impedance is 50Ω and can source up to 300mA into a low impedance
or short-circuit indefinitely.
The Manufacturers or their agents overseas will provide a repair service for any unit developing a
fault. Where owners wish to undertake their own maintenance work, this should only be done by
skilled personnel in conjunction with the service manual which may be purchased directly from the
Manufacturers or their agents overseas.
Cleaning
If the instrument requires cleaning use a cloth that is only lightly dampened with water or a mild
detergent.
WARNING! TO AVOID ELECTRIC SHOCK, OR DAMAGE TO THE INSTRUMENT, NEVER
ALLOW WATER TO GET INSIDE THE CASE. TO AVOID DAMAGE TO THE CASE NEVER
CLEAN WITH SOLVENTS.
Operation
Maintenance
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