6700 and SWR readings

AH0U

My 6700 is connected to a PGXL and a 4O3A 8x2 switch... for test purposes I have this combination connected to an Alph 2100 dummy load via an Alpha 4510 SWR meter....

On 6 meters on the Aport the 6700 shows an SWR of 2.5+ while the Alpha meter showa 1.3 which is factory spec. for the 2100 load... on the B port it shows 2.25 while the 4510 shows 1.3..... In both cases the PGXL shows 1.5.... the 6700 antenna tuner cant fine a solution so that is not in play... the question is why is the Flex reading soooooo different??

Tnx, bc AH0U

Mike-VA3MW

@AH0U

You may want to review this. It is required reading for all Hams:

https://www.arrl.org/files/file/Technology/tis/info/pdf/q1106037.pdf

Simply put, SWR is not so black and white. You will always see different SWR readings.

The SWR bridge in the radio is an actual SWR bridge unique to the rest of the hardware. To test if it is at fault, take 2 50 ohm dummy loads in parallel and see if you get a 2:1SWR reading on both ports. That is one part of the calibration process.

You should never use an ATU before an amplifier. ATU's should only be used at that antenna side of the RF chain.

Remove the AG from the chain and manually test. It is possible that is a problem with the AG. In order to test correctly, you will have to test each item one at a time with dummy loads and something like a VNA (a nanoVNA is a good choice).

Let us know how you make out.

73

AH0U

Tnx fer the comment...

I never use the ATU in the Flex on any band but have tried to use it on 6 meters.. directly without the AG in the line but it cant find a solution or it says it does sometimes but the solution is worse than without... Ill try the two 50 ohm loads but on other bands the SWR meter in the Flex seems ok

TNX ES 73 BC