General Electric

[emrr]

General Electric BA-1-F preamplifier.  Compare to Collins 356A and Langevin 5116.

 

[emrr]

Sales sheet lists 2N214 rather than 2N1304.  Also lists -25VDC @ 18mA.  I measured 10 examples which all matched my drawing.  Volume control is optional, may not be 'official'. 

 

[emrr]

160mA @ 1W output 50VDC.  100mA idle.  75dB. 

 

[envelope]

G.E. BA-7-A "Audiomatic Limiting Amplifier" circa 1957/58
2 pics attached:
First image is a packing list the contents in the box for BA-7-A showing the additional designation of 4BA7A3
Second image is the schematic labelled 4BA7A3 (BA-7-A)

these images are from the 30 page PDF technical manual ( > 45 MB) it's too large to upload...But I will eMail it to anyone who asks.

 

[ToBSn]

General Electric Uni-Level Amplifier
Model 4BA9B1
EBI-2162

 

[ToBSn]

General Electric Audio Console
Model 4BC21A1, Revision B
EBI-2179A