ALPHA 374A For Sale -
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ALPHA 374A:
$1900.00
I have an Alpha 374A fully upgraded and restored by Dick Byrd.
Repairs to Alpha 374A serial number 7043:
Lamp sockets
Lamps #85
2N3904 transistor
2N5307 darlington transistor
1000 uF, 50V electrolytic capacitor
Tantalum timer capacitor
New Front panel
wink-eye switch button, switch plunger
Step-start relay
Labor 2.5 hours
Removed and individually tested the six HV filter capacitors.
Tested HV equalizing resistors and reinstalled capacitors.
Fixed ON-OFF switch wiring error (factory recall).
Changed lamp driver transistors to proper type.
Replaced Low Voltage filter capacitor with improved type.
Amplifier would start but would turn off when the ON button was released.
Diagnosed problem and found defective primary step-start relay.
Replaced with a new unit to fix problem.
Unit would then turn on but never would time out.
Replaced timer capacitor to fix that.
Upgrades:
WARC fix This allows safe, full power operation on 12 meters.
The unmodified 374A will work just fine on 17 and 30 meters.
SO-239 RF input connector
It checked out very well on all bands at 1 kW output (RMS) key down. Slightly more on some bands
with 100 watts drive. Quite normal for this configuration.
Free shipping in the USA or OBO and I have the User Manual
Repairs to Alpha 374A serial number 7043:
Lamp sockets
Lamps #85
2N3904 transistor
2N5307 darlington transistor
1000 uF, 50V electrolytic capacitor
Tantalum timer capacitor
New Front panel
wink-eye switch button, switch plunger
Step-start relay
Labor 2.5 hours
Removed and individually tested the six HV filter capacitors.
Tested HV equalizing resistors and reinstalled capacitors.
Fixed ON-OFF switch wiring error (factory recall).
Changed lamp driver transistors to proper type.
Replaced Low Voltage filter capacitor with improved type.
Amplifier would start but would turn off when the ON button was released.
Diagnosed problem and found defective primary step-start relay.
Replaced with a new unit to fix problem.
Unit would then turn on but never would time out.
Replaced timer capacitor to fix that.
Upgrades:
WARC fix This allows safe, full power operation on 12 meters.
The unmodified 374A will work just fine on 17 and 30 meters.
SO-239 RF input connector
It checked out very well on all bands at 1 kW output (RMS) key down. Slightly more on some bands
with 100 watts drive. Quite normal for this configuration.
Free shipping in the USA or OBO and I have the User Manual
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