How to connect MFJ-998 tuner and ALS-1306 amp to a Flex 6400 ?

Larry

I am a new FlexRadio owner and need some help getting my amplifier and external antenna tuner talking with the Flex 6400.

The hardware is:

Radio: Flex 6400

Amp: Ameritron ALS-1306

ATU: MFJ-998

I purchased the Ameritron cable to go from the Flex USB to the Ameritron serial connection for Band Control Data. This cable is specific for this model amp to a Flex radio, part# DB-USB6000. So I think this will take care of the amp following the band selection on the Flex radio. 

What I am not clear on is how to get the Flex 6400 talking to the MFJ-998 antenna tuner.

With my old radio (Icom) I am able to push the tune button on the tuner and the tuner puts the radio in low power, transmits to find a tune solution, then sets the radio back to the setting before the tune started.

I want to achieve the same functionality with the Flex 6400.

Does anyone have this configuration successfully working?

M0GVZ

K2KXK

Tim - W4TME

I do not recommend using hardware ALC for exciter control.  The power level setting in SmartSDR is granular enough to prevent overdriving the amp and the max power can be set for each band and saved as a TX profile. 

Also, the amp should have sufficient protection circuitry to shut down in the event of a fault.  For the ALS-1306 this is optional, as per the manual, as it has it's own internal ALC.

In addition, Hardware ALC used with a digital radio can be too slow to make corrections fast enough to protect the amp because of the necessity of sampling an analog signal (negative voltage) and the subsequent decrease in RF power based on threshold settings.  

K2KXK

Right Tim, that's why I haven't used the hardware ALC connection.  As I mentioned, I do occasionally leave the Flex power at 100 W (accidentally) but the AMP seems to tolerate this OK in SSB.  However, I once inadvertently put 100W of FT8 into the AMP and blew one of the final transistors.  It wasn't able to protect itself against this.  I have since changed the settings in my FT8 profiles to limit the power.  I suppose I could have separate profiles for running barefoot at full power and running the AMP at reduced power but I haven't taken the time to do that.  One advantage to this approach would be that you can disable the AMP switching in the barefoot profiles.  However, I use profiles mostly to group different bands together and I'd have to double the number of profiles to take this approach.  Other comments and suggestions would be welcome.

Brian Denley KB1VBF

I use ALC to protect my amp.  I do not use it to control exciter power (nor should anyone), but as a layer of protection in case I **** up.  Are you and Tim advocating not using ALC to prevent overdriving a linear?

Tim - W4TME

Larry

Thanks Ken, for the detailed reply.  
I am going to try the setup you described.  I don't plan to use ALC, 
I'll post my results when I get it set up.

Thanks,
Larry

Brian Denley KB1VBF

Tim:
that link doesn’t work: asks me to sign in,  I did, says it doesn’t know me (?), I signed up again, now says OOPS...

Larry:
I am using that same usb cable and it works perfectly.

Alan

Tim - W4TME

@Larry - try it now.

Brian Denley KB1VBF

That worked for me.  Thanks a Tim.

Dawg Fan

I have 1306, 998 tuner and I simply switch my amp to standby to tune.  Not good for amp to tune with amp in line. I find my tuner takes about 10W to trigger tune, 5 watt is advertised minimum.

KI4P

Larry

I am having a problem getting the amp to follow the Flex.
After connecting the interface cable,
The amp would change correctly on some bands i.e. 20m, 15m
Other bands would it would change to the wrong band or error out.

I measured the BCD voltages coming out of the Amertron DB-USB6000 cable going to the amp and found that Bits 0 and 2 are reversed!

Is this a setting in the SmartSDR software that can be change?
Or did I get a bad interface cable?

Thanks,
Larry

Larry

Ned K1NJ

  You might try opening up the cable itself and exchanging the two wires rather
than dealing with the connector pins.  Proceed with caution.
     Ned,  K1NJ

                

Brian Denley KB1VBF

Brian Denley KB1VBF

Buddy Spiegel

i have the same configuration with a flex 6500. i set the parameters for the usb cable per the specs which came with the cable. auto band switching in REM mode does not work. any suggestions, please.

KD0RC

Hi Buddy, does the cable contain the FTDI chip? It will not work with the clones - it needs to be genuine FTDI.