1. HOLD: Switch will flash Red when call is present allowing operator to communicate with caller via telephone  and divert to hybrid when required. Switch momentary action. Call disconnects if pressed or caller replaces telephone. Jumper select.

2. HD: Half Duplex Switch. Allows 18 - 12 - 6dBs of caller reduction  (10)  with studio having priority. Studio noise gate on only when caller is active.

3. Tx: Transmit Gain to caller maximum level set by Limiter. Preset default setting -3dBu.

4. LIM: LED indicates limit mode. Pink noise generator (11) is set at limit  threshold.

5. BAR GRAPH: Peak reading, indicates optimum receive level, set in conjunction with (6) Rx receive gain control. The Chilton C200 Hybrid input module will automatically hold this level.

7. BAL: Allows resetting the Auto Balance for extreme line conditions ( or maladjustment ) in conjunction with preset 8 and 9 to minimises the Pink noise level on the Studio output.

10. Recessed switches with LED mode indication, select Half Duplex (2) status.

12. VOICE EQ: Selects the full range of the voice spectrum to enhance or correct the callers voice, on PFL prior to broadcast or record. This can be fine tuned with Q control ( 11). Then use the EQ IN Switch (13) for comparison. Q High is useful when boost or cut is minimal.