In the cubicle the group faders were used to ride the levels of the studio channels - this was the only design failure - you could not pre-lift any one studio channel but had to wait for it almost to get to air and lift it with the group. There were additional source faders in the cubicle of the 3 tape machines (plus a cubicle cart) and 4 outside sources which had gain tweakers and pan (PA8 297's). But each group of the 5 (carts, grams, mics and cubicle tapes and outside sources) had access to limiters. They were delay line types (AM6/11) and you could crush the sound really hard and still sound ok. There were separate lims on the mic group, mixer group and repro which enabled fabulous voice-over (again on a quadrant) control for auto gain-ducking (Noel Edmonds, Terry Wogan) and great separation for telephone calls.
There was a telephone balance module which could be plugged to OS channels, limited RSA (AM22/2 equalisers) facilities, again patchable, except for a permanent one in each mic chain (DLT's setting is etched on my brain as half top, one bass and 3 at 2.8). And of course network switching. Only six inlets and six outlets on the relay matrix and it was very crude (PA8 320). The accepting con placed his finger on the connect button and tannoyed to the releasing con to "let it go". It was usually done after the junction with the outgoing con having picked up the incoming one as a source. But it was possible to drop any network into thin air by just pressing the release.
There were a few other bits and pieces in the cubicle such as GTS inserts, OS control/cue line switching.
The desks were quite hissy but for ease of use and the sheer pleasure in moving quadrant faders they were fab. There was also a plug-in sports mixer trolley with another 12 outside sources intended for big OB operations. It could be wheeled around and plugged into the cubicle desk but to my knowledge was never used in anger.
Monitoring was usually on Spendor BC1s right in your face as there was no room for distance listening. Later (as in this photo of Con D) the bi-amped LS3/7 speakers arrived.
At one time Radio 1 used to relay Radio 2 from 7pm to 10pm (up to Sounds of the Seventies when VHF switched to Radio 1). So one evening shift job was to sit in Con B add 8dBs of compression and "monitor" the Radio 1 distribution or MW check receiver to make sure it didn't drop off! After a supper break in the pub, it was sometimes a challenge to see how many of the type D modules could be pulled out before the distribution went off. We were able to get it down to 5 remaining - but then when your monitoring module was out how could you be sure you were still on air? Intercom howling was another great pastime. Ring your colleague in sleepy old Radio 3 on his PBX phone and when he answered hold the phone to the tech intercom mic and press talk. The resultant howl/whistle/roar was very satisfying.
In fact there were many japes to be had. I recall placing a talkback speaker in the desk below Noel's feet and occasionally feeding a low dog bark off the cubicle cart to it. Keeping a straight face was the hard bit. And the all-time classic was to pre-record to tape one of Noel's records and play it in as he started the gram deck (having closed the gram group). The auto voice-over convinced him it was the record playing. After a minute I walked in and lifted the needle off the deck. Of course the output was from the tape and continued but he actually fell off his chair.
Shipping forecasts on 1500m LW were tricky if you were in Radio 2. There was a system to split the DJ desk away from the main output onto the STB output. So on an agreed pause the T.O. played a pre-rec 5 minute filler tape to VHF while the announcer warbled away on longwave. All would be rejoined on the GTS, but you had to keep your wits about you. The trickiest was a hot switch of VHF during the pips when many a time it was forgotten that Radio 1 pips were plus 8dB and Radio 2 ones only plus 4. So the last few pips suddenly dropped or rose in level.
The other great use of the type D cubicle desk was that with a sleeping bag the footwell made a great bed for nightshifts!