I just ordered a 6400 What MIC adapter will I need for a HEIL Pro 7? what special cables will I need to connect my AL-572 amp up?

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I just ordered a 6400, What MIC adapter will I need for a HEIL Pro 7? Also what special cables will I need to connect my AL-572 amp up?
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Rex Turvin

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Posted 1 year ago

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Bill Roberts

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Just a shielded audio cable with RCA male plugs on either end.
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I think Bill is directing you for the hookup between the amp and the 6400. As far as the headset I don't see a cable at Heil's website or Flex that you need. I think you can use a adapter 1/4 to 1/8 in for the audio from the headset to the input on the 6400 which for audio is 1/8 mini jack. This still doesn't give you P.T.T. I don't think,  i am not familiar with the cable you now have for the PRO7. I might add I am not at all crazy about this arrangement for audio in and P.T.T. on the back of this transceiver Maybe Flex will consult me next model HAWR
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Logan, KZ6O

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The 6400 and 6600 have the same jack setups.  Here is what I did to hook up a Pro 7 to a 6600.  The 6400 should be the same.

On the Pro 7 cable, the 3.5mm stereo plug is for the headphones and plugs directly into the 6600 PHONES jack.  The microphone is on the 3.5 mm mono plug.  I made a short jumper with a 3.5mm mono jack on one end and a 3.5mm stereo plug on the other.  I made the jumper length such that the headphone plug and new microphone plug matched up on the radio end to keep the cable run neat.

For the jumper, I used a piece of small diameter, multi conductor shielded cable that I had in the "leftovers box." I used one conductor to connect the jack tip to the plug tip, the ring on the plug on the radio end of the jumper has no connection.  The cable was shielded and I connected the ground wire to the sleeve on the jack and plug. The stereo plug goes into the 3.5 mm MIC jack on the 6600.

I set the microphone gain to +20 db in the SmartSDR Settings->Radio Setup->Phone/CW.  Bias is not needed.  It works great.

I did not rig up a PTT; I use the MOX button in SmartSDR.  I don't have a Maestro and do everything on the computer.  It's just as easy to click a mouse button as it is the click/push a PTT switch.  Plus my hand stays on the mouse so I'm ready to make any changes that might be needed.  And it's one less cable and device to deal with on the desk.  But that's a personal choice, YMMV.

I you want a PTT switch, you will need a cable with an RCA phono plug on one end and a matching jack for your PTT device on the other.

For the amp, you just need a cable with RCA phono plugs on both ends.  One end plugs into TX1 on the back of the radio and the other end goes to the PTT input on the amp.  Then you need to enable RCA TX1 in Settings->Radio Setup->TX.  I use this setup with my ACOM 1010.

I hope this helps.

Logan, KZ6O
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Michael Walker, Technologist

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Hi Rex

If you want to give us a call at the shop we can figure it out for you.  However, that answers above are very good too!