GU-74B NOS 4CX800A NOS Tube GU74B with BOX

Description

ONE New, Nos tube GU-74B / 4CX800A in unopened plastic pack
with original box
You buy what you see at the picture
With green stripe and blue stamp OTK
Note
: All GU-74B tubes require proper conditioning (gettering) after long time storage
before they can be used in the equipment.
Failure to do proper conditioning may result in permanent damage to the tube
see info:
blog.kotarak.net/2009/02/gettering-gu74b-4cx800a.html
You can also simply hold the tube for 10 hours
under incandescence
without anode voltage
and
with anode cooling
.
During this time, the getter absorbs possible residual gases.
Operating Values -
Name: GU74B;
Type: tetrode;
Cathode type: oxide, indirect heating;
Application field: power amplification in broadcasting and SSB equipment;
Brief application: amplification;
Envelope: metall-ceramic;
Cooling method: forced air;
Dimensions: 90mm x 71mm;
Mass: 0.55 kg;
Filament voltage: 12.6 V;
Filament current: 3.3 - 3.9 A;
Mutual conductance: 26 to 38 mA/V;
Limit Operating Values -
Heater voltage (AC or DC), V 11.9-13.3
Heater current, A 3.3-3.9
Anode voltage, V: DC 2000  peak value 4000
Grid 2 voltage (DC), V 300
Negative grid 1 voltage, absolute value, V -150
Cathode current mA: DC component 750 peak value 2500
Dissipation, W: anode 600
Operating frequency, MHz 250
Shipping is due within 3 business days by Airmail with a track number.
73 GL dit-dit  :)