Warning: JIS-C7001 is abandoned. Those data are for reference only.

There is no warranty with this contents.


JAPANESE INDUSTRIAL STANDARD JIS

Type Designation System for Receiving Tubes C 7001-1965 (Reaffirmed: 1970)

1. Scope

This standard specifies designating system for receiving tubes.

 

2. Composition of Types

The types designation shall consist of number symbols, letter symbols and suffix letter symbol as shown in the following arrangements.
1st item 2nd item - 3rd item 4th item 5th item
Number symbol Letter symbol Hyphen Letter symbol Number symbol Suffix

 

 

3. Number Symbols of 1st Item

The number symbols of the first item shall consist of one or more digits indicating the rated filament or heater voltage of the receiving tube in accordance with the Table 1. In case the tapped filament or heater, the number symbols shall indicate the total rated voltage of the filament or heater section operated in series at the rated current, and in case the tube has a plural of filament or heater sections, the number symbols shall indicate the total voltage of these filament or heater sections operated in series.

 

Table 1 
Rated voltage of filament or heater Number symbol of 1st Item
Cold cathode 0
Over 0 V through 1.6 V 1
Over 1.6 V through 2.6 V 2
Over 2.6 V through 3.6 V 3
Over 3.6 V through 4.6 V 4
Over (n-0.4 V through n+0.6 V) n

Remarks: n shall be an integer longer than 1.

4. Letter symbols of 2nd Item

Letter symbols given in Table 2 shall be used for the second item in compliance with the

classification of base, lead or terminal of the receiving tube.

Table 2  
Classification of 

Base or terminal

Classification of outlines Letter symbol 

Of 2nd item

Reference figure
A 4-5, A 4-9 ST tube(4 pin) X Fig. 1
A 5-6, A 5-11 ST tube (5 pin) Y Fig. 1
A 6-7, A 6-12 ST tube (6 pin) Z Fig. 1
A 7-8 ST tube (7 pin) W Fig. 1
Octal base Series of GT tube, G tube, etc. G Figs. 2, 3, 4
E 7-1 Miniature tube (7 pin) M Fig. 5
E 9-1, E 9-37, 

E 9-68, E 9-82

Miniature tube (9 pin), ninar 

Tube, neonoval tube

R Figs. 6, 7, 8
D 8-1 Lock-in tube L Fig. 9
Subminiature, 

Round button base

(including E 8-9,E 8-10)

Round button subminiature tube 

(including those with external shield)

D Figs. 10, 11
Subminiature, 

Pinch press base

Round body, pinch press base 

Subminiature tube,

Flat body, pinch press base

Subminiature tube

E Figs. 12, 13
Series of E 12-64 Nuvistor N Fig. 14
E 9-23, E 9-75, 

E 8-76, E-9-88,

E 9-89

Magnoval tube, novar tube, etc. H Figs. 15, 16, 17
E 12-70, E 12-74 Duodecar tube (for instance Compactron) C Figs. 18, 19
Terminal Ceramic tube K Fig. 20
Other than above B

 

5. Letter Symbols of 3rd Item

Letter symbols given in Table 3 shall be used for the third item in compliance with the construction and use of the receiving tube. In case of multiunit tube, however, the corresponding number of letter symbols of Table 3 shall be used in alphabetical combination.

 

Table 3 
Construction Principal use Letter symbol 

Of 3rd item

Diode Detector, rectifier D
High vacuum diode Rectifier (for power supply) K
Gas filled diode   G
Triode (with amplification 

Factor 30 or more)

Amplifier H
Triode (with amplification 

Factor less than 30)

Detector, amplifier (except 

Power amplifier)

L
Triode Power amplifier A
Space-charge grid tube Detector, amplifier S
Tetrode, pentode   R
Tetrode, pentode Variable amplifier V
Tetrode, pentode Power amplifier P
Beam power tube   B
Multi-grid tube Frequency converter C
Fluorescent indicating tube Tuning indicator E
Others Others U

6. Number Symbols of 4th Item . 

A serial number of the fourth item shall be used, as a rule, to discriminate the characteristics of the receiving tube having the same letter symbol for the third item. As regards the rectifier for power supply, however, an odd number shall be used for the half-wave rectifier and an even number for the full-wave rectifier.

 

7. Combination of Letter Symbols of 2nd Item, Letter Symbols of 3rd Item and Number Symbols of 4th Item 

A combination of the letter symbols of the second item, letter symbols of the third item and numerals of the fourth item is called a family. This combination. alone shall establish a tube type family whose members differ only in one or more of the following. A family symbols for any one family shall be used only for the tube types within that family. 

(1) Voltage and current ratings of either filament or heater. The wattage rating of the filament or heater may differ from the first type registered, but the numerical difference between the highest and lowest members of a family shall not exceed 25% of the wattage of the first type registered. When the first registration includes two or more members of a family, the highest wattage member governs. 

(2) Heater and cathode voltage rating.

 

8. Suffix Letter Symbol of 5th Item

The suffix letter symbol of the fifth item shall be used to distinguish the modification from the original version or modified version, in compliance with the following.

(1) Capital letters A, B, C, D, E and F shall be suffixed in the order of the modification of the original version.

(2) The modified version can be substituted for any lower suffix letter version but not vice versa.

(3) Suffix letter shall be assigned to a new or to modified version of a family member such that this member has the same suffix letter as other members of the same family incorporating the same modifications.

 

9. Examples of Type Number

Examples of type number of receiving tubes complying with this standard as given below:

Examples

1. Rated heater voltage 2.5 V, 7-pin miniature tube, variable amplifier pentode, with characteristics 1: 2M-V1

2. Rated filament voltage 1.4 V, pinch press base subminiature tube, detector and amplifier pentode, with characteristics 2: lE-R2

3. Rated heater voltage 6.3 V, GT tube, multiunit tube composed of detector diode and triode with high amplification factor, with characteristics 4: 6G-DH4

4. Example 1, but with heater warm-up time specified ; capable of replacing the former type, and same letter and numeral designation up to the 4th item: 2M-VlA

5. Example of Family

Tube similar to Example 3 6G-DH4 (heater current 300 mA) changed to heater voltage 3.15 V (heater current 600 mA) with the characteristics same as before: 3G-DH4

These receiving tubes belong to the family.