Date: Wed, 11 Nov 92 11:54:37 EST
From: jas@proteon.com (John A. Shriver)
Subject: EL34 tube data

Since people have been interested about how to use EL34 tubes in
various classes of operation, and good tube data is so hard to come by
these days, I decided to type in the data for the EL34.  

This comes from the Sylvania Electronic Tubes Technical Manual,
Twelfth Edition.  This is better than the RCA bound tube handbooks
(RC-nn).  The RCA HB-3 covers more tubes, but often in not as much
depth, and is usually not as up to date.

(I've supplemented with with data from the Tung-Sol tube handbook, as
reprinted in the VTL Book.  I left out all the Class B data from that
source!  If anyone knows where I can get "recent" Tung-Sol and Amperex
tube data books, let me know.)

The 6CA7/EL34 data seems to be derived directly from the Mullard data.
The illustration is of the Mullard metal-base version.

I take no responsibilities for typos!

MAXIMUM RATINGS (Design Center Values)

					Triode	Pentode
					Conn.	Conn.

Plate Voltage				500	800	Volts
Plate Voltage Without Plate Current		2000	Volts
Grid No. 2 Voltage				425	Volts
Grid No. 2 Voltage Without Plate Current	800	Volts
Plate Dissipation			30	25	Watts
Plate Dissipation Without Input Signal		27.5	Watts
Grid No. 2 Dissipation				8	Watts
Cathode Current					150	Ma
Grid No. 1 Circuit Resistance
   Cathode Bias				0.7*	0.7*	megohms

* The maximum permissible limit for Grid No. 1 Resistor in a Class B
  Circuit is 0.5 megohms.

CHARACTERISTICS AND TYPICAL OPERATION

Pentode Operation Single Tube, Grid Bias:

Plate Voltage				265	265	Volts
Grid No. 2 Voltage			250	250	Volts
Grid No. 2 Resistor			2000	0	Ohms 
Grid No. 1 Voltage			-14.5	-13.5	Volts
A-F Grid Voltage (RMS)			9.3	8.7	Volts
Zero Signal Plate Current		70	100	Ma
Zero Signal Grid No. 2 Current		10	15	Ma
Transconductance			9K	11K	Micromhos
Plate Resistance			18K	15K	Ohms
Load Resistance				3K	2K	Ohms
Power Output				8	11	Watts
Total Harmonic Distortion		10	10	Percent

Pentode Operation Single Tube, Cathode Bias:

Plate Voltage				300	Volts
Grid No. 2 Voltage			300	Volts
Cathode Resistor			190	Ohms
A-F Grid Voltage (RMS)			8.2	Volts
Zero Signal Plate Current		83	Ma
Zero Signal Grid No. 2 Current		13	Ma
Load Resistance				3.5K	Ohms
Power Output				11	Watts
Total Harmonic Distortion		10	Percent

Triode Operation Push-Pull, Cathode Bias [I assume Class A]:

Plate Voltage				400	Volts
Cathode Resistor			220	Ohms
Zero Signal Plate Current		130	Ma
Max. Signal Plate Current		142	Ma
Load Resistance				5K	Ohms
Power Output				16.5	Watts
Total Harmonic Distortion		3	Percent

Class AB1 Pentode Operation Push-Pull, Cathode Bias:
(All currents for both tubes.)

Plate Voltage				375	450	Volts
Grid No. 2 Voltage			375	450	Volts
Common Grid No. 2 Resistor		470	1000	Ohms
Cathode Resistor			130	232	Ohms
A-F Grid Voltage (RMS)			20	27	Volts
Zero Signal Plate Current		150	120	Ma
Max. Signal Plate Current		188	143	Ma
Zero Signal Grid No. 2 Current		25	20	Ma
Max. Signal Grid No. 2 Current		39	44	Ma
Load Resistance (P to P)		3.5K	6.5K	Ohms
Power Output				35	40	Watts
Total Harmonic Distortion		1.7	5.1	Percent

Class AB1 Pentode Operation Push-Pull, Grid Bias:
(All currents for both tubes.)

Plate Voltage				400	Volts
Grid No. 2 Voltage			400 	Volts
Common Grid No. 2 Resistor		800	Ohms
Grid No. 1 Voltage			-36	Volts
A-F Grid Voltage (RMS)			25	Volts
Zero Signal Plate Current		60	Ma
Max. Signal Plate Current		221	Ma
Zero Signal Grid No. 2 Current		9	Ma
Max. Signal Grid No. 2 Current		46	Ma
Load Resistance (P to P)		3.5K	Ohms
Power Output				54	Watts
Total Harmonic Distortion		1.6	Percent

Class AB1 Push-Pull Ultra-Linear Operation, Cathode Bias:
Grid No. 2 at 43% of Primary Winding
(All currents for both tubes.)

Plate Voltage				430	430	Volts
Cathode Resistor			235	235	Ohms
A-F Grid Voltage (RMS)			17.5	25	Volts
Zero Signal Plate Current		125	125	Ma
Max. Signal Plate Current		130	140	Ma
Zero Signal Grid No. 2 Current		20	20	Ma
Max. Signal Grid No. 2 Current		20.4	18	Ma
Load Resistance (P to P)		6K	6K	Ohms
Power Output				20	34	Watts
Total Harmonic Distortion		0.35	2.5	Percent