▼ Menu

UM4

 
See also:
Tuning Indicators
    
Extras ▼

 

The UM4 tuning indicator from Mullard has dual sensitivity, the 10M2 is directly equivalent. The grid voltage change can be 4.2 V or 12.5 V.
See also EM4.
The control element is clearly visible in the centre of the picture.
The wide glass tube envelope is 26 mm in diameter and, excluding the IO base pins, is 73 mm tall.
References: Data-sheet, 3002 & 1040. Type UM4 was first introduced in 1940. See also 1940 adverts.

 

Pin Connections
IO
1
2
3
4
5
6
7
8
h
ic
a(2)
t
g1
a(1)
k
h

 

Absolute Maximum Operating Conditions
Indicator
Vh
Ah
Va
mAa
12.6
0.1
300
1.4
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated November 18, 2013.
Return to Main Index