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What is the frequency coverage of the SG-500 linear amplifier?
The SG-500 covers 1.8 - 24.5 MHz. Properly licensed operators can extend the coverage to 30 MHz.

What is the power output of the SG-500?
The SG-500 is rated at 500 watts CW output. This will vary somewhat depending on drive level, power supply voltage, frequency of operation, load VSWR etc. SSB PEP may be somewhat higher. Exciter power for full output is about 50 watts.

What are the power requirements for the SG-500?
The SG-500 requires 12 volts DC, and up to 90 amps in CW mode. The average SSB current is 40 amps.

What kind of power supply is suitable for the SG-500?
For operation from A.C. we suggest the use of our PS-50 power supplies. Use 1 PS-50 for SSB, and 2 for CW and data. We strongly discourage the use of inexpensive regulated power supplies. For operation from DC we suggest that you float a 100 AH battery near the unit. Ask for a copy of our Go Mobile at 500 watts publication for complete details.

What kind of protection circuitry does the SG-500 have?
The SG-500 is completely protected by microprocessor control, which monitors the following parameters: SWR, current, current balance, voltage, drive level, and temperature. If any of these parameters should go outside pre determined limits, the amplifier switches out of the circuit.

How are the PTT and band switching functions accomplished?
PTT and band switching may be configured for fully automatic operation. This type of operation is well suited to remotely located amplifiers. Of course you may choose to configure the unit for conventional (manual) PTT and band switching.

Is there a remote kit available?
Yes, the remote kit provides LED status indicators, power switch, and band switch, and comes with 20' of cable. (cat# 52-88)

I do RTTY a lot, do I need a cooling fan?
Yes, for data, or other severe service, the optional cooling fan kit is required. The kit is not needed for normal SSB service.

What is the maximum permitted drive level for the SG-500?
You may drive the SG-500 with up to 150 watts. The microprocessor controlled input attenuator will reduce the drive to a safe level. For most efficient operation, the drive level should be set to about 50 watts.

Why does the gray wire coming from the antenna tuner go to the PTT of the Amplifier and the brown wire from the antenna tuner go to the PTT ground of the Icom IC710. Why don't you just direct the PTT ground from the 710 to the amplifier PTT?
This is done for a very good technical reason. It is to activate the amplifier only when the coupler has succeeded to a proper tune. In other words the SG-500 is in the by pass mode until the coupler has tuned with the output power of the radio (100 watts), then when tuned the coupler will activate the SG-500. This provides a safe and reliable operation for the SG-235 and SG-500.

Does the SG-500 work with Pactor II?
Yes. The amplifier must be set in Manual PTT and Manual Filter to do this.