[Johnson] Invader 2000

Tue, 27 Apr 2004 07:50:05 -0400

However, TDSL does NOT show the 4-400A as a viable substitute to use in the 
Invader 2000 in place of theior specified PL-175A.

Maybe some have done this but apparebntly the two tubes are 
in fact different.

PL-175A
Power Tetrode
Data Source and Substitute Data
Prefered Substitutes .......................... None
Substitutes ................................... None
Mechanical Data
EIA Base ...................................... F86Electrical Data
Heater CharacteristicsHeater Voltage ................................ 5 VoltsHeater Current 
................................ 14.5 AmperesDirect Interelectrode Capacitances (approx)
TetrodeInput ......................................... 15.1 pfOutput 
........................................ 9.8 pfGrid to Plate ................................. 0.06 
pfMaximum Ratings (Design Center Values)
TetrodePlate Voltage ................................. 4000 VoltsGrid No. 2 Voltage 
............................ 600 VoltsPlate Dissipation ............................. 400 WattsGrid 
No. 2 Dissipation ........................ 25 WattsCharacteristics and Typical Operation
Class C Amplifier/Class C Modulated Amplifier (Plate)Plate Voltage 
................................. 4000 VoltsGrid No. 3 Voltage ............................ 0 
VoltsGrid No. 2 Voltage ............................ 600 VoltsGrid No. 1 Voltage 
............................ -200 VoltsGrid No. 1 Current ............................ 6 Ma.Plate 
Current (Zero Signal) ................... 350 Ma.Grid No. 2 Current (Zero Signal) 
.............. 29 Ma.Driving Power ................................. 1.4 WattsPower Output 
(approx) ......................... 960 WattsClass C Amplifier/Class C Modulated 
Amplifier (Plate)Plate Voltage ................................. 2500 VoltsGrid No. 3 Voltage 
............................ 0 VoltsGrid No. 2 Voltage ............................ 600 VoltsGrid 
No. 1 Voltage ............................ -180 VoltsGrid No. 1 Current 
............................ 7 Ma.Plate Current (Zero Signal) ................... 350 Ma.Grid 
No. 2 Current (Zero Signal) .............. 40 Ma.Driving Power 
................................. 1.6 WattsPower Output (approx) ......................... 600 
WattsClass AB1 AmplifierPlate Voltage ................................. 2500 VoltsGrid No. 
2 Voltage ............................ 750 VoltsGrid No. 1 Voltage ............................ -
143 VoltsPeak Grid No. 1 Voltage ....................... 143 VoltsPlate Current (Zero 
Signal) ................... 100 Ma.Plate Current (Maximum Signal) ................ 350 
Ma.Grid No. 2 Current (Zero Signal) .............. 1 Ma.Grid No. 2 Current (Maximum 
Signal) ........... 35 Ma.Driving Power ................................. 0 WattsPower Output 
(approx) ......................... 570 WattsClass AB1 AmplifierPlate Voltage 
................................. 3000 VoltsGrid No. 2 Voltage ............................ 750 
VoltsGrid No. 1 Voltage ............................ -150 VoltsPeak Grid No. 1 Voltage 
....................... 150 VoltsPlate Current (Zero Signal) ................... 80 Ma.Plate 
Current (Maximum Signal) ................ 350 Ma.Grid No. 2 Current (Zero Signal) 
.............. 1 Ma.Grid No. 2 Current (Maximum Signal) ........... 29 Ma.Driving 
Power ................................. 0 WattsPower Output (approx) ......................... 
680 WattsClass AB1 AmplifierPlate Voltage ................................. 3500 VoltsGrid 
No. 2 Voltage ............................ 750 VoltsGrid No. 1 Voltage ............................ 
-160 VoltsPeak Grid No. 1 Voltage ....................... 160 VoltsPlate Current (Zero 
Signal) ................... 75 Ma.Plate Current (Maximum Signal) ................ 350 
Ma.Grid No. 2 Current (Zero Signal) .............. 1 Ma.Grid No. 2 Current (Maximum 
Signal) ........... 24 Ma.Driving Power ................................. 0 WattsPower Output 
(approx) ......................... 790 Watts

On 26 Apr 2004 at 11:43, Roy Morgan wrote:

> At 09:39 AM 4/26/2004 -0400, George Shapow wrote:
> >Hi all,
> >
> >I have an Invader 2000 in need of finals.  It uses PL-175As but I've
> >been told that 4-400s are direct substitutes.  Is that true?
> 
> George,
> 
> It may not be true. (Unless you put in a different socket, or change
> operating conditions, perhaps.)
> 
> This link shows no preferred or normal substitutes:
> <http://www.nj7p.org/cgi-bin/tube?tube=PL-175A>
> 
> The PL-175A has EIA Base F86
> 
> The 4-400 has  EIA Base 5BK  (I cannot tell you the difference.)
> 
> Roy
> 
> 
> 
> 
> 
> >George Also, Does anyone
> >know where I can get them at a reasonable price?
> >
> >Thanks
> >
> >George, NY2O
> >
> >
> >_______________________________________________
> >Johnson mailing list
> >[email protected]
> >http://mailman.qth.net/mailman/listinfo/johnson
> 
> - Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
> 7130 Panorama Drive, Derwood MD 20855
> Home: 301-330-8828 Work: Voice: 301-975-3254,  Fax: 301-948-6213
> [email protected] --
> 
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