Racal MA.251 Buffer Amplifier

September 2015:

When an RA.66 Panoramic Display is used in conjunction with either an RA.17 or RA.17L it is first necessary to fit an MA.251 Buffer Amplifier between the receiver’s 2nd and 3rd mixer stages. RA.66s are very rare and sought after. MA.251s are even rarer.

MA.251
to RA.66
SK4 on 2nd VFO R61 in RA17(L)

Genuine MA.251 from RA17L N3372. Note: The BNC and mini Burndept connectors are swapped.

Integration of MA.251 in an RA.17L

5
1
2
6
7
3
4

MA.251 schematic