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PTT and Multi-function Buttons
The ESP Hub PTT has three PTT buttons marked 1, 2 and 3 on one side of the hub. On the other side there
is a fourth PTT marked 4 and a multi-function button (MFB) below PTT 4.
•The PTT 1 button controls the primary device plugged into the jack
labeled PTT 1-2 MAIN.
•The PTT 2 button controls the secondary device plugged into the
jack labeled PTT 1-2 MAIN.
•The PTT 3 button controls the primary device plugged into the jack
labeled PTT 3 AUX
•The PTT 4 button controls the secondary device plugged into the
jack labeled PTT 3 AUX.
•The MFB is used to configure or control various ESP Hub PTT
features such as toggling the Spatial Audio Positioning and Mic
mode features.
Radio Configuration
1. Radios that will be powering the hub must have an accessory power supply capable of 200mW and
be configured for 5V.
2. The spatial audio performance is optimal when the radio’s internal speaker is disabled while the
headset speaker is enabled.
3. When the Mic Mode is PTT, the radio should be configured for accessory PTT. In Hot Mic Mode, hub
PTT or radio PTT may be used.
Device Operation
Note that the connectors on the ESP Hub PTT are keyed to create proper alignment of the connector pins.
1. Plug the audio connector cable on the OTTO® headset into the jack marked HDST on the top of the
hub.
2. Plug a device connector cable into the bottom of the hub. The cable must be the appropriate cable
for the device in use. Plug the other end of the cable into the device.
3. Devices plugged into the MAIN jack are controlled by PTT 1 and 2.
4. Devices plugged into the AUX jack are controlled by PTT 3 and 4.
5. When using a Y cable, the radio that is to supply power must be connected to the shorter lead of
the cable labeled PTT1.
6. When using a straight single channel cable, devices plugged into MAIN use PTT 1. Devices plugged
into AUX use PTT 3.
7. Listening volume for radio communications is controlled by the volume controls on the radios.
8. The Mic Mode on a channel is toggled between PTT and Hot by simultaneously pressing the MFB and
the PTT button for that channel.
