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Magnum S680 29.090mhz only

OL, nothing

That's with meter on 2k setting, then 20k setting, then 200k setting, them 20m setting.

With meter in 200/beep setting, I get a brief beep and numbers jump from 1000 down to 0 then OL. Reverse leads and get a brief beep and the meter jumps from 1500 down to 0 then OL.

On diode setting I get 1000 one way and 1500 the other way.

Numbers are not exact, just approximate.
OL, nothing
There's a chance it's a bit out of spec.

You might also want to check resistance of the circuit past the inductor to make sure there's not a short there. If the inductor did it's best fuse impression because of excessive current draw a new one would probably repeat the performance.
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Inductor L100 is cracked between the silver and red stripe. Pictures always help.

Good eyes, I didn't even notice that
Now to see if I can find one of the same value in a parts radio.

Thank you, I'll update y'all once I find a replacement.
Well, I have no 1mH, but I do have a 5.6uh. Not sure if it'll work. Just might order one and put this radio on the side till the part comes in.
Maybe this is not a big issue and hopefully someone else can chime in on it, but I have often wondered about inductors that get hot like that.

Assuming nothing is shorted elsewhere on the board and the heat that caused that crack is from regular use, does that not suggest the inductor is being used at or near saturation? And if it is being used at saturation, wouldn't its ability to block RF be diminished to some degree? I know for most materials, saturation doesn't happen at a well-defined current, but when I see typical saturation currents of 25-50% the rated DC current listed on mouser, that heat crack has me curious.

Am I going overboard to to think its a good idea to jump that bad inductor with a milliamp meter to see what the DC current draw is so that an inductor with a higher saturation current can be found???
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I went ahead and ordered an assortment, which includes the 1mH 10% I need.

When the part comes in, then I'll update on the outcome.

Right now I've got an oldie on the desk. A President Dwight D (AM only, non 858, 25/29 style board layout). Owner wanted transmit fixed (had no xmit), variable key and complete alignment done to it. I've already got the xmit issue fixed, now just got to throw in a variable key (going the R49 route) and then align it.

Thank you guys for helping out, when the part gets here, I'll throw it in and give an update.
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Your gonna have to remove that board from the metal shell to look under it for sure. Could have gotten hot from solder balls under the board especially under those 3 diodes. Don't be surprised if it needs a 5v regulator too. The regulator is a LM78L05.
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Mine looks just like the one pictured as above.

Pin 1 and pin 4 are jumpered (ON state).

Where would I look for the reset button, if it has one?

Also, this radio has no display of any kind. Channel indicator does not light up, frequency counter does not light up and neither does the meter light. When I first turn the power on, the meter light will flicker on then off and stay off until I turn the radio off and back on, then the meter light will flicker on then off again.

I checked the 8v regulator and the small regulator that's against the 8v regulator, the voltages on those are correct.

It's as though half the radio works, while the other part doesn't switch on.

Meter works,
All controls work (except Band, channel and 10khz),
Transmit works

Just stuck on one frequency and has no display at all, no lights.

This thread has probably gone beyond me being able to help but here is what I was referring to earlier. If you scroll down near the end in this review you will see the small board with the con ports, the black round button was the CPU reset. Magnum went through different phases on how easy or difficult it was to convert these radio's back then based on how unhappy the FCC was with them at that moment. Anyway here is the link, I was hoping your S6 had this small board in it.

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I got the parts but had to finish up a couple other radios and get them out the door before I finish this one up. I'm expecting the reg is gonna be what caused it to go out, but I'll have to wait and see if the reg is good after I put in the inductor.

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