Cobra 148 GTL S/RF CAL SWR switch and meter problem

[cdennislll]

I also have this issue now unit 75 did you ever find out the cause?

 

[Robalo]

have you try with new meter or unlock the top screw mmmm, could be mechanical issue

 

[cdennislll]

have you try with new meter or unlock the top screw mmmm, could be mechanical issue

Ronald thanks for the reply I have just acquired this radio recently. Work fine on ssb just am seeing .63 mv across s meter used vr1 to get it down but that isn't the fix. Will look into it just found my old sams I copied from the library.

 

[Handy Andy]

Since you've got the radio, but not owned it thru the years (same radio) then this may simply be a mis-tuned section of the "twin IF coil" section that both SSB and AM pair with.

You'll see this in the SAMS for it as well as on the board itself.

 

[cdennislll]

Since you've got the radio, but not owned it thru the years (same radio) then this may simply be a mis-tuned section of the "twin IF coil" section that both SSB and AM pair with.

You'll see this in the SAMS for it as well as on the board itself.

Will check it out thank you

 

[Handy Andy]

Here...


This is for RX IF - note the pairs of coils together.

One type looks like a typical IF coil can be found in most AM radios - the WIDE slot RED, Black and Amber - which are for the radios AM IF side.

The other two - using a 2mm - fine slotted - are the SSB IF ones.

Since IF processing is similar, they put and use the same strip to handle both types of IF and use the passing of one IF - it only peaks in one set of coils, or so it should - leakage is possible so alignment is critical and if not done right you can peak to the other IF coil passage and generate a leaky IF problem similar to yours.