|   |   | 
				 
				HF pentode for battery receivers 
				The KF4M is a military version 
				Introduced in 1936 
				
					
						| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | tc | base |  
						| m | -f | +f | - | g3 | - | g2 | a | g1 | P |    
				
					
						| Vf | Af | Va | Vs | Vg | mAa | mAs | ra | gm | Pdiss |  
						| 2 | 0.065 | 90 | 90 | -0.5 | 1.2 | 0.4 | 900,000 | 0.7 | 0.5 |    
					
						
							| Equivalent | 2J2M*, 
							2B4, BHP61, TKF4 |  *) octal base |