Gerry, As with any amplifier ---
Connect the K3 output coax to the AL82 input coax, and connect the K3 KEYOUT to the AL82 PTT IN (or whatever they call it). Forget the ALC cable - instead, adjust the K3 power output to drive the AL82 to its full output (or whatever you want below that level), and use that as the maximum when driving the amplifier. The amplifier instructions may tell you to connect an ALC line too. Be aware that using the amp's ALC to control the drive power is a recipe for distortion no matter what the amplifier may be. If you do choose to connect the ALC line, use it only as an amplifier fault control - adjust the drive power as I stated, and all will work fine.
A word on keying the amplifier (yes, even in semi QSK). Ameritron amplifiers are famous for their slow open frame relays (there are QSK mods to change those relays and eliminate the problem), but the K3 semi QSK mode does not increase the time between KEYOUT and the onset of RF. (There is a K3 menu parameter to increase that timing). Semi QSK does extend the cessation of RF keying to the time the K3 goes back to receive mode, and can eliminate relay chatter in the amplifier.
If you can extend the K3 TX DLY parameter sufficiently to assure that you will not hot switch the amplifier, then all will be fine, but if the delay time provided is not sufficient, you will be forced to use a footswitch (or other means) to activate keying of the amplifier before you start CW keying or SSB audio.
Note that I have not looked up the time from keying the amp to the relay settling, but that time is typically greater than the K3 8 ms. default KEYOUT to onset of RF timing.
In other words, semi QSK controls the training edge of the KEYOUT signal, but does not change the leading edge. TX DLY will control the leading edge up to the limit of its range.
If you increase TX DLY significantly, listen to your signal to be certain that leading CW elements (or SSB syllables) are not truncated by the delay parameter.
73, Don W3FPR On 12/24/2012 6:21 PM, Scott James wrote:
I do not have my K3 yet. I have been reading about it. I would like to use it with an Ameritron AL82 in semi QSK (vox on). I do not see an amp connection mentioned in the manual What is the hook up for a non QSK amp to the K3? Tks very much Gerry
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