Flex-6700 External GPSDO Questions

Ed, K0KC

Al K0VM

Tim - W4TME

Tim - W4TME

Steve Sterling

Ed, K0KC

Al K0VM

Ed, K0KC

WX7Y

Ed, K0KC

Thanks, Bret!

How would I know that my 6700 has lost lock? I normally turn the 6700 off each night, so I might not see the problem arise.

Ed, K0KC

WX7Y

Ed, K0KC

roger na4rr

Geoff AB6BT

Just curious, why do you have to increase the offset? What happens when you run the calibration routine against WWV?

roger na4rr

Geoff AB6BT

Copy, standing by...

Steve Sterling

Just like it should.

Ed, K0KC

Tim - W4TME

There is actually a defect in the 6700 where the 2m frequency is off regardless if you use WWV or CHU to frequency calibrate the radio.  If you use an external driver XO (GPS or Rb), the frequency error is corrected.

Ed, K0KC

This is what I discovered accidentally...a pleasant surprise!

Ed, K0KC

Ed, K0KC

WX7Y

Ed, K0KC

Yep, Bret, you warned me!

I will experiment a bit more, but I have a feeling this is something that will not be under my control.

Larry _ NY8T

My 6700 does the same with the Trimble and BG7TBL GPSDO's.

KD0RC

WX7Y

this is only on the 6700 my 6600 works great

Ed, K0KC

It appears that I have identified my problem with the Flex-6700 losing lock with the GPSDO. I sometimes have the 6700 running when I work 2 meter FT8 on my IC-9700 with no issues on the 6700 which stays locked to the GPSDO

I also sometimes operate 6 meter FT8 with my IC-7700 while my 6700 is running. Today I noticed that the 6 meter RF (either in the shack or coupled into closely-spaced antennas) causes the Flex to lose lock. Once the Flex loses lock, I have to shut SmartSDR down and power-down the 6700 and then calibrate the 6700 against the GPSDO again after turning the 6700 back on and re-starting SmartSDR.

In my tests today, the 6700 has stayed locked to the GPSDO for over 5 hours once I identified the problem and stopped operating on 6 meters. I plan to let the 6700 run overnight to see if it maintains lock.

Apparently the RF on 6 meters adversely affects the 6700, but not the IC-9700 or the GPSDO. The solution for me will be to ensure that the 6700 is turned off when I operate 6 meters...I cannot address my antenna limitations at this point in time.

Bret and Larry, this does not sound like the issue that you guys are experiencing, but I though that I would share my solution with you and the group just in case it helps.

Ed, K0KC

KD0RC

Good catch Ed. You might try some ferrites on the GPSDO cables if you have not done that yet.  Other cables could also be causing the problem, so don't stop at the GPS if the problem persists.

73,
Len, KD0RC

Al K0VM

Larry _ NY8T

I choked everything on my gpsdo and divider, we will see.

Ed, K0KC

In some tests yesterday and today, my Flex-6700 has stayed locked to the GPSDO for at least 12 hours but lost lock overnight.

In a test today, it lost lock on its own (without any RF in the shack) after only a few hours.

To get it to lock again, I typically have to close SmartSDR, power down the 6700 and turn off the power supply for a short time and then restart the 6700, SmartSDR, and then run the calibration routine.

I have not yet tried ferrites or grounding the GPSDO case, but the tests indicate that loss of lock occurs even without any RFI.

Ed, K0KC