.Subaudible tone

An optional subaudible tone unit TU-8 is available for installation in the TS-440S for accessing 10 meter FM

repeaters. This tone is activated whenever the TS-440S is in the SPLIT mode.

3-3-4. AM mode

1.Set the Meter switch to PWR.

2.Set the MODE key to AM.

3.Place the Standby switch to SEND.

4.Adjust the CAR control so that the meter indicates 25 watts.

5.Place the Meter switch to ALC.

6.Adjust the MIC gain control so that the meter deflection does not exceed ALC zone on voice peaks.

3-4. AUTOMATIC ANTENNA TUNER (The AT unit AT -440 is required for this function.)

The automatic antenna tuner operates within the amateur radio bands from 3.5 thru 29.7 MHz.

1.Ensure that an antenna designed for use within the band you intend to operate on is properly connect- ed to the antenna terminal.

2.Set the AUTO/THRU switch to the AUTO position,

3.Place the A T TUNE switch to the ON position. The AT TUNE indicator will light and the tuner will be- gin tuning. Then the CW mode indicator will light.

4.After a short period the ATTUNE indicator will go OFF and the motors will stop turning.

5.Place the ATTUNE switch to OFF

6.Tuning is now completed. You may now carry out normal communications.

Notes:

1.When the AT TUNE switch is ON and the AT indi-

cator lights but then goes out immediately it is an indication that the antenna was not that far off resonance and that tuning has been completed.

2.Normal operation is not possible until the ATTUNE switch has been turned OFF.

3.If the motors do not stop turning after approximately 30 seconds, place the AT TUNE switch to OFF, and then back to ON again. The tuner will attempt to tune again, and should find a good match. If the tuner will not stop after several tries it indicates some problem exists with the antenna system. Readjust the antenna and feedline before attempt- ing to tune again.

3-5. DUAL DIGITAL VFO's

Operational convenience can be enhanced thru the use of both VFO A and VFO B.

3-5-1. Why two VFO's

Occasionally OX stations will utilize an operational procedure known as split frequency operation. When the OX station is in this mode he will be transmitting on one frequency and receiving on another. This is done in order for the OX station to be able to recog- nize the calls of stations during pile-ups.

Older transceivers required the use of an external VFO to allow this split frequency operation. The TS-440S, thru the use of microprocessor controls, effectively pro- vides two separate VFOs in the same package. Several different controls and switches have been provided to increase the operators convenience when faced with this type of operation. The use of these controls is dis-

cussed below.

3-5-2. Split frequency

(a) A=B switch

Depressing this switch causes the data contained in the inactive VFO (the VFO that is not currently being displayed) to change to the same data con- tained in the active VFO (the one currently dis-

played). Both the frequency and mode are

changed.

For example: VFO A is set at 7 MHz in LSB, and VFO B is 21 MHz in USB. VFO A is the active VFO (show on the display). Depressing the A = B switch will cause VFO B to change to 7 MHz in LSB.

(b)A/B switch

Allows selection of the desired active VFO. Each time this switch is depressed the active VFO will alternate between VFO A and VFO B.

(c)SPLIT switch

Allows the use of one VFO for transmit, and the other for receive (Split Frequency operation). For example: VFO A is the active VFO, and VFO B is the inactive VFO. Depressing the SPLIT switch will cause the TS-440S to receive on VFO A and trans- mit on VFO B. The mode of reception and trans- mission will follow the mode contained in the appropriate VFO memory. It is possible to work cross band, cross mode if desired.

To avoid confusion during contest, or pile-up oper- ations we recommend using VFO A for receive and VFO B for transmit.

(d)T -F SET switch

Depressing this switch will allow you to rapidly set or check the transmit frequency, during SPLIT

operations, without the need of actually trans- mitting.

This switch is especially convenient when you are trying to locate the transmit frequency of the sta- tion currently in contact with the OX station, since

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Image 14
Kenwood TS-440S manual Dual Digital VFOs, Changed, Cussed below