Tapping in an external S meter

[sparky17]

I run a live videogate, and wanted to use my base radio instead of my secondary radio. This requires a second S meter external to the radio.

I'm cheap and have meter movements, so I was planning on adding an RCA jack to the back of the radio and running that out to an external meter.

I figured I could just use an opamp as a voltage follower and tap into the existing meter, but wasn't having much luck...

(- and output are tied on the opamp, input is going in on the +)

Worst case I can do it with a microcontroller, but I figured there'd be an easy way to add a second S meter to a radio.. This is on a Cobra 2000. I have tons of parts, just wondering if I'm trying to reinvent the wheel, or if I'm over complicating things..

[sparky17]

Put two RCA jacks in the back of the radio, and ran the second meter in series. I put a potentiometer across the meter leads and adjusted it until both meters read the same..

It did load it down, but it only dropped the S meter calibration down by 1 S unit which is acceptable..

[Night Crawler]

Adjust the S meter calibration potentiometer on the circuit board in the radio to bring it back up that 1 S unit.