Workman HP202S calibration question.

[881TX6666]

I have a workman 202S meter and the 100 watt and 1000 watt scales are off. I opened it up and see the 6 pots. I assume 3 are for forward power for each scale and the other 3 are for reflect in each scale. I want to calibrate it or at least get it as close as possible to my Daiwa CN-901hp that I know is accurate. Does anyone know what pot adjust what on the workman?
I’ve emailed workman a couple times and it’s been a month and I haven’t got any response. I don’t really want to just blindly more each pot to see what it does because the 10 watt scale seems to be dead on. I bought it to run in my mobile so I don’t have to run my more expensive Daiwa while driving in my city with huge potholes.
Thanks,
881 Texas

 

[sp5it]

Schematic attached.

 

[881TX6666]

Schematic attached.

Awesome! Thanks so much!

 

[Recon]

I have a workman 202S meter and the 100 watt and 1000 watt scales are off. I opened it up and see the 6 pots. I assume 3 are for forward power for each scale and the other 3 are for reflect in each scale. I want to calibrate it or at least get it as close as possible to my Daiwa CN-901hp that I know is accurate. Does anyone know what pot adjust what on the workmantwore each pot to see what it does because the 10 watt scale seems to be dead on. I bought it to run in my mobile so I don’t have to run my more expensive Daiwa while driving in my city with huge potholes.
Thanks,
881 Texas

I recently returned my new Daiwa CN-901HP3 to Amazon because when I compared the readings of the Daiwa to two BIRD watt meters, there was a four-watt difference on the 0–30-watt scale and a six-watt difference on the 0–3000-watt scale.
The batteries in both BIRD watt meters are two weeks old. I'll admit the watt meters and elements have not been calibrated since 2020 but both BIRD meters indicate the same watts.
No problem with returning the Daiwa to Amazon. They gave me a choice to return the Daiwa for another CN-901HP3 or credit my payment to my credit card. I selected Door #2!

 

[881TX6666]

I recently returned my new Daiwa CN-901HP3 to Amazon because when I compared the readings of the Daiwa to two BIRD watt meters, there was a four-watt difference on the 0–30-watt scale and a six-watt difference on the 0–3000-watt scale.
The batteries in both BIRD watt meters are two weeks old. I'll admit the watt meters and elements have not been calibrated since 2020 but both BIRD meters indicate the same watts.
No problem with returning the Daiwa to Amazon. They gave me a choice to return the Daiwa for another CN-901HP3 or credit my payment to my credit card. I selected Door #2!

Used one of my professors birds to check mine. Was well within the plus or minus 5% difference on all scales. Actually less than 3% on all scales. I made sure to use the element closest to the wattage that was being produced. Not doing that can make a good difference. Even bird meters are “accurate” to plus or minus 5% when newly calibrated. That’s the standard on most good meters. Some being higher. I quote accurate because with RF watt meters you can only be so accurate when it’s capable of measuring a range of frequencies.
Six watts on the 3000 scale is very accurate but the 4 watts on the 30 watt scale isn’t, that’s about 13%. Shouldn’t be any more than plus or minus 1.5 watts on the 30 watt scale.