Vertex Standard FT-1000MP Rtty Operation, Baud Packet, AM Transmission, Digital Mode Operation

OPERATION

TRANSMITTING

AM TRANSMISSION

Transmitter setup for the AM mode is essentially the same as for LSB or USB, except that you must avoid overmodulating, and limit carrier power to 50 watts. This carrier level ensures that sufficient power is available for the voice sideband envelopes.

rVOX can be used in the AM mode, but for now, make sure the [VOX] switch is off, so as not to con- fuse adjustments.

rWith the AM mode selected, press the METER [ALC/COMP] button to view the ALC range.

rPress the PTT switch, and rotate the RF PWR con- trol for the desired power output (remember to limit transmitter carrier power to 50 watts in the AM mode).

rIf you have already set the MIC control as described for SSB transmission, there should be no need to readjust it. If not, close the PTT switch, and adjust this control just to the point where the ALC begins to deflect slightly, and stays within the red ALC zone. Don’t set it too far beyond this point, or your signal will become distorted from over-modulation.

rThe transmit monitor is very helpful in setting the correct modulation level, and if you have head- phones on, you should turn the monitor on now.

Note that the speech processor is disabled in the AM mode. You can, however, activate the VOX, if de- sired.

DIGITAL MODE OPERATION

Information regarding connection of your MARK-VFT-1000MPto commonly-available digital-mode mo- dem devices is presented beginning on page 15.

Operating practices generally are governed by de- tails provided in the operating manual for the TNC or modem you are using. However, a few guidelines are presented below, to help you get on the air quickly.

RTTY Operation

To operate, just press the RTTY mode button once or twice to select the desired sideband for operation. LSB is default, and is used by normal convention (USB can be selected for MARS or other applications). Should you need reverse tone polarity or non-standard shift (other than 170 Hz), configure menu selection 6-1and 6-2as desired.

RTTY TONE/SHIFT INFORMATION

Shift	High Tone Pairø		Low Tone Pair
	Mark	Space	Mark	Space
170 Hzø	2125 Hz	2295 Hz	1275 Hz	1445 Hz
425 Hz	2125 Hz	2550 Hz	1275 Hz	1700 Hz
850 Hz	2125 Hz	2975 Hz	1275 Hz	2125 Hz

øindicates default setting (used by normal convention)

For optimum signal-to-noise ratio, use the 250-Hz or 500-Hz BANDWIDTH selection for 170-Hz shift, the 500-Hz selection for 425-Hz shift, or the 2.0-kHz se- lection for 850-Hz shift. Remember that the Sub VFO receiver bandwidth is only selectable between 6.0 kHz,

2.4kHz and 500 Hz (optional YF-100required) for RTTY (and PKT).

Note that for AMTOR operation, you must have the VOX button off, and may need to set the AGC control to “FAST” or “OFF” (and reduce the setting of the RF Gain control) for Mode A (ARQ).

300-Baud Packet

Construct a patch cable as required, and connect your TNC to the rear-panel PACKET jack. Do not con- nect the squelch line (pin 5) for 300-baud packet op- eration.

Tuning is very critical for F1 packet: you should tune the transmitter and receiver within 10 Hz of a signal to minimize repeats. The MARK-VFT-1000MPincludes a few custom features to make packet operation more convenient.

Packet Tone Pair - This offsets the center of the IF bandpass according to the packet tone pair you are using. If set correctly, the receiver passband will re- main centered on a properly-tuned packet station when switching between wide and narrow IF filters, minimiz-

MARK-V FT-1000MP Operating Manual page 57