BA7
- 50 -
of any of 150 pairs of programme monitoring points to any
or all of three monitoring positions. First used
Broadcasting House Extension. DD 1958. DD Spec 3.179.
OBSOLESCENT.
==========================================================================
BA7 Sub Group not available for new designs DD 1977.
BA9/l
BA9/2
BA9/3
BA9/4
BA9/5
BA9/5A
BA9/6
BA9/7
BA9/8
BA9/9
BA9 EQUIPPED UNISELECTOR SWITCHING BAY
Bay, Switching, Source/Route for selection by remote
control of any of 50 programme channels to each of 12
programme
routes.
First
used
Glasgow.
DD 1957/58.
DD Spec 3.147. OBSOLESCENT.
EMX Switching Bay 100
DD 1957/58. DD Spec 3.146.
line. First
OBSOLESCENT.
used
Glasgow.
Bay, Switching, EMX 200 line. Type 9 bay with Siemens
standard
apparatus.
First
used
Broadcasting
House
Extension. DD 1957/58. DD Spec 3.178. OBSOLESCENT.
Source/Route Switching Bay for selection by remote control
of anyone of 100 programme sources to each of 12
programme
routes.
Siemens
equipment.
First
used
Manchester. DD 1957/58. DD Spec 3.232. OBSOLESCENT.
Source/Route Switching Bay. Facilities for selection by
remote control of anyone of 50 programme circuits to each
of 12 routes, each circuit having up to 4 wires. Type 9
Bay with standard Siemens motor uniselectors etc. First
used Broadcasting House. DD 1957/58. DD Spec 3.164.
OBSOLESCENT.
Similar to BA9/5 but with 100 programme circuits each with
two wires. DD 1957/58. DD Spec 3.294. OBSOLESCENT.
Bay, Switching, Source A. Consists of Siemens equipment
on Type 9 bay. Used with BA9/7 for selection by remote
control of anyone of one hundred programme sources to
each of 12 programme channels. Broadcasting House
Extension. DD 1957/58. DD Spec 3.180. OBSOLESCENT.
Bay, Switching, Source B. Used with BA9/6. DD 1957/58.
DD Spec 3.181. OBSOLESCENT.
Bay, Switching, Source CiD. Used with BA9/6 and BA9/7 for
selection of a further fifty programme sources.
DD 1957/58. DD Spec 3.182. OBSOLESCENT.
Bay, Switching, Source A. Similar to BA9/6
motor unise1ectors are 8 level instead of
available switching levels instead of 12).
DD Spec 3.183. OBSOLESCENT.
except that
18 level (4
DD 1957/58.

50