Nagai superstar 3900 freq plan p!ease

[original45]

Image showing rear of potentiometer and second image showing green wire from that very potentiometer to the resister on board.
Hope this helps identify if it is a variable power pot as well as swr cal and where i can obtain a replacement please. Cheers .
Apologies in reply to the question of image .radio was put away a while over xmas.atvb

[cb4ever104]

That's just your standard DIY variable power on the SWR CAL . Usually the SWR CAL is bypassed/jumpered on the SWR switch and it gets used to vary the AM/FM power instead . You've got a few choices :

1) Fix your rotating SWR CAL and rewire it to stock and use the VR to set it to 4W . (My choice)

2) Get hold of a pull switch that operates the SWR CAL when in and power when out . Don't know where you would get one . Aliexpress or similar ? Or maybe an old Dirland or something , although I'm not sure of the value of those DSF filter controls .

3) Fix your rotating SWR CAL and leave it as is (Variable power)

The SWR CAL and VR are both 5Ks .

Sammy

[original45]

Thank you confirmed my thought as standard. I did buy a standard swr cal pot for 3900 .Will now consider how it gets wired.
I don't need variable rf output, I too prefer 4 or 5 watt so I think we know where this is going here.

Thank you as ever my friend .love this site ,so many knowledgeable folk willing to share.

If only now I had the skills to sort it .hopefully a friend will come to the rescue again
Atvb.
Bless ya

[14CS06]

Hello



https://radio-media-system.com/p/potentiometre-swr-cal

@+
Claude

[cb4ever104]

No problem. The SWR CAL wiring is the same in all of these. If you download the wiring diagram for the Cobra 148 GTL-DX MK2 then you'll be able to see how it's wired. The Ranger is the same.

[original45]

Thank you claude and Sammy. The link is excellent indeed. Atvb