Hubbell 670-801-UL, 670-801-EX InternalAdjustments, Offset Level, VLC Level, FSK Transmit Level

	Pub. 42004-615L2
Model 670-801-EX and 670-801-UL SmartSeries Amplifiers	Page: 11 of 15

Offset Level

The Offset Level adjustment causes the speaker amplifier to maintain a set difference between the ambient level and the speaker output level. The SmartVolume™ feature measures the ambient noise at the associated speaker and adds the Offset Level to set the speaker amplifier gain. This keeps page announcements louder than the ambient noise. The Offset Level can be set from 0 dB (the speaker output level is the same as the ambient level) to 49 dB. A speaker should be set for 6 to 10 dB louder than the ambient noise, so the factory default is 9 dB.

To adjust the Offset Level, perform the following steps:

NOTE: There must be enough ambient noise for the amplifier to sense. The exact level depends upon the speaker type, but it is typically approximately 80 dB.

1.Turn USER ADJ fully clockwise and wait to hear two beeps over the associated speaker.

This switches the amplifier into the Offset Level adjustment mode. If there is an audio signal on the page line when the amplifier enters this mode, you hear it over the speaker. Otherwise, you hear an amplifier-generated test tone.

2.Turn USER ADJ counterclockwise to the desired speaker volume level.

The amplifier remains in the Offset Level adjustment mode for as long as USER ADJ is varying. After USER ADJ has remained stable for five seconds, the amplifier returns to its normal operating mode.

VLC Level

The VLC Level adjustment sets the speaker amplifier gain for the Page Priority VLC feature to provide an emergency output level. The amplifier can be set from minimum to full output (12 watts into 8 ohms) in 100 discrete steps, or to no output. The factory default is step 10, but the System VLC Control feature is disabled.

To adjust the VLC Level, perform the following steps:

1.Have an assistant page from a station that forces the amplifier being adjusted into VLC mode.

2.Turn USER ADJ fully counterclockwise and wait to hear two beeps over the amplifier’s associated speaker.

This switches the amplifier into the VLC Level adjustment mode.

3.Turn USER ADJ clockwise to the desired speaker volume level.

The amplifier remains in the VLC Level adjustment mode for as long as USER ADJ is varying. After USER ADJ has remained stable for five seconds, the amplifier returns to its normal operating mode.

InternalAdjustments

This assembly includes additional internal control, the FSK Transmit Level, which affects system performance. Therefore, only qualified GAI-Tronics personnel with the appropriate test equipment should make any adjustments. The function and location are included for information only. Tampering with this control may void your warranty.

FSK Transmit Level

The control labeled XMIT LEVEL adjusts the level of the frequency shift keying (FSK) signal transmitted to the page line.

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