SECO 78 Tube Tester

Make a selection and click 'Go'.

Select a Tube 1AX2 1B3 1G3 1H2 1J3 1K3 1S2 1X2 1Z2 2AF4 2B3 2BN4 2C22 2C50 2C50 2C52 2C52 2CY5 2D21 2E6 2EA5 2EN5 2EN5 2ER5 2ER5 2ES5 2ES5 2J2 2T4 2V3 2W3 3A2 3A3 3AF4 3AL5 3AU6 3AV6 3AV6 3AV6 3B2 3BA6 3BC5 3BE6 3BN4 3BN6 3BU8 3BY6 3BZ6 3C2 3CE5 3CF6 3CS6 3CY5 3DK6 3DT6 3EA5 4AU6 4BA6 4BC5 4BC8 4BC8 4BE6 4BN4 4BN6 4BQ7 4BQ7 4BS8 4BS8 4BU8 4BX8 4BX8 4BZ6 4BZ7 4BZ7 4BZ8 4BZ8 4CB6 4CE5 4CS6 4CX7 4CX7 4CY5 4DE6 4DK6 4DT6 4ES8 4ES8 4EW6 5AM8 5AM8 5AN8 5AN8 5AQ5 5AR4 5AR4 5AS4 5AS4 5AS8 5AS8 5AT8 5AT8 5AU4 5AU4 5AV8 5AV8 5AW4 5AW4 5AX4 5AX4 5AZ4 5AZ4 5B8 5B8 5BE8 5BE8 5BK7 5BK7 5BQ5 5BQ7 5BQ7 5BR8 5BR8 5BS8 5BS8 5BT8 5BT8 5BT8 5BW8 5BW8 5BW8 5BZ7 5BZ7 5CG4 5CG4 5CG8 5CG8 5CL8 5CL8 5CM6 5CM8 5CM8 5CQ8 5CQ8 5CR8 5CR8 5CZ5 5DB4 5DB4 5DH8 5DH8 5EA8 5EA8 5EH8 5EH8 5EU5 5EU5 5FV8 5FV8 5GH8 5GH8 5J6 5J6 5R4 5R4 5T4 5T4 5T8 5T8 5T8 5T8 5U4 5U4 5U8 5U8 5V3 5V3 5V4 5V4 5V6 5W4 5W4 5X4 5X4 5X8 5X8 5Y3 5Y3 5Y4 5Y4 5Z4 5Z4 6A8 6AB4 6AB7 6AB8 6AB8 6AC5 6AC6 6AC7 6AD5 6AD7 6AD7 6AD8 6AD8 6AD8 6AE5 6AE6 6AE7 6AE7 6AE8 6AE8 6AF3 6AF4 6AF5 6AG5 6AG6 6AG7 6AH4 6AH5 6AH6 6AH7 6AH7 6AJ5 6AJ7 6AJ8 6AJ8 6AK5 6AK6 6AK7 6AK8 6AK8 6AK8 6AK8 6AL5 6AL5 6AL6 6AM5 6AM6 6AM8 6AM8 6AN4 6AN5 6AN7 6AN7 6AN8 6AN8 6AQ4 6AQ5 6AQ6 6AQ6 6AQ6 6AQ7 6AQ7 6AQ7 6AQ8 6AQ8 6AR5 6AR8 6AS5 6AS6 6AS7 6AS7 6AS8 6AS8 6AT6 6AT6 6AT6 6AT8 6AT8 6AU4 6AU5 6AU6 6AU7 6AU7 6AU8 6AU8 6AV4 6AV4 6AV5 6AV6 6AV6 6AV6 6AV8 6AV8 6AW7 6AW7 6AW7 6AW8 6AW8 6AX4 6AX5 6AX5 6AX6 6AX6 6AX7 6AX7 6AX8 6AX8 6AZ8 6AZ8 6B3 6B4 6B6G 6B6G 6B6G 6B8 6B8 6B8 6BA6 6BA7 6BA8 6BA8 6BC4 6BC5 6BC6 6BC7 6BC7 6BC7 6BC8 6BC8 6BD4 6BD5 6BD6 6BD7 6BD7 6BD7 6BE6 6BE7 6BE8 6BE8 6BF5 6BF6 6BF6 6BG6 6BH5 6BH6 6BH8 6BH8 6BJ5 6BJ6 6BJ7 6BJ7 6BJ7 6BJ8 6BJ8 6BJ8 6BK4 6BK5 6BK6 6BK6 6BK6 6BK7 6BK7 6BK8 6BL4 6BL7 6BL7 6BL8 6BL8 6BM5 6BM8 6BM8 6BN4 6BN5 6BN6 6BN7 6BN7 6BN8 6BN8 6BN8 6BQ5 6BQ6 6BQ7 6BQ7 6BR7 6BR8 6BR8 6BS5 6BS7 6BS8 6BS8 6BT4 6BT4 6BT6 6BT6 6BT6 6BT8 6BT8 6BT8 6BU4 6BU5 6BU6 6BU6 6BU6 6BU8 6BV7 6BV7 6BV7 6BV8 6BV8 6BV8 6BW4 6BW4 6BW6 6BW7 6BW8 6BW8 6BW8 6BX4 6BX4 6BX6 6BX7 6BX7 6BX8 6BX8 6BY5 6BY5 6BY6 6BY7 6BY8 6BY8 6BZ6 6BZ7 6BZ7 6BZ8 6BZ8 6C4 6C5 6C8 6C8 6CA4 6CA4 6CA5 6CA7 6CB5 6CB6 6CD6 6CE5 6CF6 6CG6 6CG7 6CG7 6CG8 6CG8 6CH6 6CH7 6CH7 6CH8 6CH8 6CJ5 6CJ6 6CK4 6CK5 6CK6 6CL5 6CL6 6CL8 6CL8 6CM6 6CM7 6CM7 6CM8 6CM8 6CN6 6CN7 6CN7 6CN7 6CQ6 6CQ8 6CQ8 6CR5 6CR6 6CR6 6CR8 6CR8 *6CS5 6CS6 6CS7 6CS7 6CS8 6CS8 6CU5 6CU6 6CU8 6CU8 6CW5 6CX7 6CX8 6CX8 6CY5 6CY7 6CY7 6CZ5 6D4 6D8 6DA4 6DA6 6DA7 6DB5 6DB6 6DC6 6DE4 6DE6 6DE7 6DE7 6DG6 6DG7 6DH8 6DH8 6DJ8 6DJ8 6DK6 6DN6 6DN7 6DN7 6DQ5 6DQ6 6DR6 6DR7 6DR7 6DS5 6DT5 6DT6 6DT8 6DT8 6DW5 6DY7 6DY7 6DZ7 6DZ7 6E8 6E8 6EA5 6EA7 6EA7 6EA8 6EA8 6EB5 6EB5 6EB8 6EB8 6EF6 6EH5 6EH8 6EH8 6EM5 6ER5 6ER5 6ES5 6ES5 6ES6 6ES8 6ES8 6ET6 6EU8 6EU8 6EW6 6EX6 6EY6 6F5 6F6 6F8 6F8 6FH8 6FM8 6FM8 6FM8 6FV6 6FV8 6FV8 6FY8 6FY8 6G6 6G7 6GH8 6GH8 6H4 6H6 6H6 6H7 6H7 6H8 6H8 6H8 6J4 6J5 6J6 6J6 6J7 6J8 6J8 6K5 6K6 6K7 6K8 6L5 6L6 6L7 6M5 6M6 6M7 6M8 6M8 6M8 6N4 6N6G 6N7 6N7 6N8 6N8 6N8 6P5 6P8 6P8 6Q4 6Q5 6Q6 6Q6 6Q7 6Q7 6Q7 6R4 6R6 6R7 6R7 6R7 6R8 6R8 6R8 6R8 6S2 6S4 6S5 6S6 6S7 6S8 6S8 6S8 6S8 6SA7 6SB7 6SC7 6SC7 6SD7 6SE7 6SF5 6SF7 6SF7 6SG7 6SH7 6SJ7 6SK7 6SL7 6SL7 6SN7 6SN7 6SQ7 6SQ7 6SQ7 6SR7 6SR7 6SR7 6SS7 6ST7 6ST7 6ST7 6SU7 6SU7 6SV7 6SV7 6SZ7 6SZ7 6SZ7 6T4 6T6 6T7 6T7 6T7 6T8 6T8 6T8 6T8 6U3 6U4 6U6 6U7 6U8 6U8 6V3 6V4 6V4 6V5 6V6 6V7 6V7 6V7 6V8 6V8 6V8 6V8 6W4 6W5 6W5 6W6 6W7 6X4 6X4 6X5 6X5 6X6 6X8 6X8 6Y3 6Y6 6Y7 6Y7 6Z6 6Z7 6Z7 6ZY5 6ZY5 7A4 7A5 7A6 7A6 7A7 7A8 7AD7 7AF7 7AF7 7AG7 7AH7 7AJ7 7AK7 7AN7 7AN7 7AU7 7AU7 7B4 7B5 7B6 7B6 7B6 7B7 7B8 7C4 7C5 7C6 7C6 7C6 7C7 7D7 7DJ8 7DJ8 7E6 7E6 7E6 7E7 7E7 7E7 7EY6 7F7 7F7 7G7 7G8 7G8 7H7 7J7 7J7 7K7 7K7 7K7 7L7 7N7 7N7 7Q7 7R7 7R7 7R7 7S7 7S7 7T7 7V7 7W7 7X6 7X6 7X7 7X7 7X7 7Y4 7Y4 7Z4 7Z4 8AU8 8AU8 8AW8 8AW8 8BA8 8BA8 8BH8 8BH8 8BN8 8BN8 8BN8 8BQ5 8BQ7 8BQ7 8CG7 8CG7 8CM7 8CM7 8CN7 8CN7 8CN7 8CS7 8CS7 8CX8 8CX8 8CY7 8CY7 8EB8 8EB8 8EM5 8SN7 8SN7 9A8 9A8 9AK8 9AK8 9AK8 9AK8 9AQ8 9AQ8 9AU7 9AU7 9BM5 9BR7 9BR7 9BR7 9BR8 9BR8 9BW6 9CL8 9CL8 9EF6 9EJ5 9U8 9X8 9X8 10C8 10C8 10DA7 10DA7 10DE7 10DE7 10DR7 10DR7 10EB8 10EB8 10EG7 10EG7 11C5 11CY7 11CY7 12A4 12A6 12A8 12AB5 12AC6 12AD5 12AD6 12AD7 12AD7 12AE6 12AE6 12AE6 12AE7 12AE7 12AF3 12AF6 12AG6 12AH7 12AH7 12AH8 12AH8 12AJ6 12AJ6 12AJ6 12AJ7 12AJ7 12AL5 12AL5 12AL8 12AL8 12AQ5 12AT6 12AT6 12AT6 12AT7 12AT7 12AU6 12AU7 12AU7 12AV5 12AV6 12AV6 12AV6 12AV7 12AV7 12AW6 12AW7 12AX4 12AX7 12AX7 12AY7 12AY7 12AZ7 12AZ7 12B3 12B4 12B6 12B7 12B8 12B8 12BA6 12BA7 12BD6 12BE6 12BF6 12BF6 12BF6 12BH7 12BH7 12BK5 12BK6 12BK6 12BK6 12BL6 12BN6 12BO6 12BR7 12BR7 12BR7 12BT6 12BT6 12BT6 12BU6 12BU6 12BU6 12BV7 12BW4 12BW4 12BY7 12BZ6 12BZ7 12BZ7 12C5 12C8 12C8 12C8 12CA5 12CM6 12CN5 12CR5 12CR6 12CR6 12CS5 12CS6 12CS7 12CS7 12CT8 12CT8 12CU5 12CU6 12CW6 12CX6 12CY6 12D4 12DB5 12DE8 12DE8 12DF5 12DF5 12DF7 12DF7 12DK5 12DK7 12DK7 12DK7 12DL8 12DL8 12DL8 12DM5 12DM7 12DM7 12DQ6 12DQ7 12DS7 12DS7 12DS7 12DT5 12DT7 12DT7 12DT8 12DT8 12DU7 12DU7 12DU7 12DV7 12DV7 12DV7 12DV8 12DV8 12DV8 12DW5 12DW7 12DW7 12DW8 12DW8 12DW8 12DY8 12DY8 12DZ6 12E5 12EA6 12EC8 12EC8 12ED5 12EF6 12EG6 12EH5 12EK6 12EL6 12EL6 12EL6 12EM6 12EM6 12EN6 12EZ6 12F5 12F8 12F8 12F8 12FA6 12FK6 12FK6 12FK6 12FM6 12FM6 12FM6 12FQ8 12FQ8 12FT6 12FT6 12FT6 12FY8 12FY8 12G4 12G7 12G7 12G7 12G8 12G8 12H6 12H6 12J5 12J7 12J8 12J8 12J8 12K5 12K7 12K8 12L6 12Q7 12Q7 12Q7 12R5 12S8 12S8 12S8 12S8 12SA7 12SB7 12SB8 12SB8 12SB8 12SC7 12SC7 12SF5 12SF7 12SF7 12SG7 12SH7 12SJ7 12SK7 12SL7 12SL7 12SN7 12SN7 12SQ7 12SQ7 12SQ7 12SR7 12SR7 12SR7 12SW7 12SW7 12SW7 12SX7 12SX7 12SY7 12U7 12U7 12V6 12W6 12X4 12X4 13DE7 13DE7 13DR7 13DR7 14R7 14R7 14R7 14S7 14S7 14W7 14X7 14X7 14X7 14Y4 14Y4 14Y7 14Y7 15A6 15A8 15A8 16A5 17AV5 17AX4 17BQ6 17C5 17C8 17C8 17C8 17CA5 17D4 17DE4 17DQ6 17H3 17L6 17R5 17Z3 18A5 18AK5 18AQ5 18FW6 18FX6 18FY6 18FY6 18FY6 18GD6 18GE6 18GE6 18GE6 18J6 18J6 19AQ5 19AU4 19BG6 19C8 19C8 19C8 19C8 19DE7 19DE7 19J6 19J6 19T8 19T8 19T8 19T8 19V8 19V8 19V8 19V8 19X3 19X8 19X8 19Y3 21A6 21A7 21A7 21B6 21EX6 22DE4 25A6 25A7 25A7 25AC5 25AC7 25AV5 25AX4 25B6 25B8 25B8 25BK5 25BQ6 25C5 25C6 25CA5 25CD6 25CG6 25CR5 25CU6 25D4 25D8 25D8 25D8 25DN6 25DQ6 25DT5 25E5 25EC6 25EH5 25F5 25FY8 25FY8 25L6 25N6 25U4 25W4 25W6 25X6 25X6 25Y4 25Z4 25Z6 25Z6 26A6 26BK6 26BK6 26BK6 26C6 26C6 26C6 26CG6 26D6 26E6 26Z5W 26Z5W 28D7 28D7 28Z5 28Z5 30A5 31A3 32ET5 32L7 32L7 35A5 35A6 35B5 35C5 35CD6 35L6 35W4 35Y4 35Z3 35Z4 35Z5 35Z6 35Z6 36AM3 38A3 40Z5 45A5 45 B5 45Z5 50A5 50AX6 50AX6 50B5 50BK5 50BM8 50BM8 50C5 50C6 50CA5 50CD6 50DC4 50EH5 50FY8 50FY8 50L6 50X6 50X6 50Y6 50Y6 50Y7 50Y7 50Z6 50Z6 50Z7 50Z7 55N3 ⇐ Select a tube type and click 'Go'.     ::SECO 78 Instructions

ID	Tube	IC	Fil. Volts	R	Load	L	Notes
1	1AX2		1	H	100	X	Special Socket 30% OK
2	1B3		1	H	100	y
3	1G3	*	1	H	0	y
4	1H2		1	H	100	X	Special Socket
5	1J3	*	1	H	100	Y
6	1K3	*	1	H	100	Y
7	1S2		1	H	100	X	Special Socket
8	1X2		1	H	100	X	Special Socket
9	1Z2		1	H	100	X	Special Socket
10	2AF4	*	2	B	40	Y
11	2B3		2	H	100	Y
12	2BN4	*	2	B	35	X
13	2C22		6	H	45
14	2C50		12	A	55
15	2C50		12	C	55
16	2C52		12	A	60
17	2C52		12	C	60
18	2CY5		2	A	45	X
19	2D21		6	A	30	X
20	2E6		6	D	50	X

Important

For additional technical data see last pages for tube chart index.

OPERATING INSTRUCTIONS

BEFORE YOU TEST

1. Set the "Function Switch" to its mid-position.

2. Set the Switch "L" to position marked "NORMAL"

3. Push the slide switch to "ON" position.

4. Allow a half minute for the tester warm up.

5. The meter pointer should rise to renter scale to the mark labeled "Line Adjust". Adjust control on the panel marked "Line Adjust" with a small screwdriver, if necessary.

TESTING

6. CAUTION: DO NOT INSERT THE TUBE INTO ITS SOCKET UNTIL ALL CONTROLS ARE PROPERLY SET UP.

7. Locate the tube to be tested on the set-up card.

Example:

Tube Type = 6AU4

Fil. V. = 6

Sw. "R" = D

Load = 50

Sw. "L" = Leave in "normal" unless indicated by X, Y, or Z

8. Set up the controls as indicated.

9. Insert the tube in its socket. There-are two nine-pin sockets. The one at the tipper left is only used when indicated in the tube set-up.

10. Place the cap clip on top of the tube if one is used.

11. As the tube warms up the meter pointer will gradually read into the "GOOD" area on the right side of the scale. REJECT THE TUBE IF IT READS IN THE RED "REPLACE" area.

12. Push the "Function Switch" forward to the position marked "GCT SHORTS AND LEAKAGE" and tap the tube gently. A good tube should read in the "GOOD" area at the left end of the meter scale. REJECT THE TUBE IF THE POINTER JUMPS INTO THE RED AREA OR STAYS IN THE RED AREA.

13. Tubes having two or more entries on the set-up require more than one test. Set controls as indicated and proceed to test again. NOTE: on many types having two entries it is only necessary to move the SELECTOR SWITCH "R".

14. If it is desired to check a tube for filament continuity ONLY then pull the "FUNCTION" switch to position marked "FILAMENT CONTINUITY". The meter should read in the "GOOD" on the right side of the meter scale if continuity exists.