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[N4WRO]

I finally decided to get a amplifier to mate with the IC-7300.  Picked up a good deal on a ALS 600.

Being brand new to the use of any type of amplifier, during my research, I see where some folks are calling for a buffer between the devices.  The one from K4POZ comes to mind ($40.00), along with the Ameritron ARB-704.  That one also requires additional cables.  ($120.00 range with the cable)

I do see that the transmit delay should be set to 25ms on the radio.

The question is, are any of these devices really required to operate this combination.

Thanks for any and all suggestions/information.  I dont want to screw this up. 

[K6AER]

Take the key line output from the 7300 and connect the cable to the amplifier key line input. Set the 7300 RF output to the recommended amplifier input level.

Make sure your antenna is 50 ohms input impedance. If not you will need an antenna tuner that will handle 600 watts minimum.

You do not need an ALC cable. The 7300 will keep the power at the level you set it for.

[W0CKI]

You do not need a buffer. You do not need an ALC connection. Some may argue differently. You do need a resonant antenna and you may need an antenna tuner between the amplifier and the antenna.

[W9AC]

The answer to the question depends on two factors:

1) Do you operate full break-in modes like CW or VOX?

2) Do the ALS 600's T/R relays switch faster than the Icom 7300 SEND line?

The IC-7300 has a firmware problem where the SEND line releases before the RF envelope decays to zero in break-in modes.  This cannot be cured in the IC-7300's menu by extending the TX Delay time.  The latest Icom IC-7300 firmware still manifests with the timing problem.

A discussion of the problem and one potential fix is linked below:

http://www.wb6bbb.com/Icom_IC-7300/default.html

Regardless of the answer to the above questions, I have developed a small PC board, the size of a matchbook that solves the problem more easily than the invasive mod described in the link above.  It functions as both a key line buffer and SEND line pulse stretcher.  Contact me at my ARRL address if there's an interest. 

Paul, W9AC

[N4WRO]

Thanks to everyone for the information.

Yes, I have a LDG 1000 Pro II tuner inline with this setup.  This feeds a EFHW 8010 antenna which I have been more than pleased with.  On 75 meters, SWR was way out of specs, with the tuner, it brings it down to 1.2-1.3.  All the other bands run around the same with none higher than 1.4.

Again....   Thanks!