Rf sampler smoked out my radio

[Tallman]

So with the scope on I got 24 volts DC on the front frame when I touch my multimeter meter from ground to front plate cover! Even with scope off I got 24 volts. I unplug scope, drops to zero. What the hell

Is the voltage just on the front panel or all of the exterior of the case?
Measure again with the volt meter set to AC volts.

 

[Robb]

Open ground in the AC wall socket supplying the scope?

 

[Captain Kilowatt]

Unless i missed it you never did say what the
end of the power cord for the scope has for a plug. Three pin grounded? Two pins with one blade wider than the other? Two pins both the same width? I just checked my Tektronix 465 scope and it has a three pin grounded plug. just wondering if yours has been replaced and possibly wired wrong by having the hot and neutral reversed.

 

[unit_399]

All of this discussion about the sampler, the 'scope and the house AC service is nice, but I believe the reason the radio smoked was due to "HUMAN ERROR". When 805 repaired the burnt trace, he soldered the jumper to wrong place on the board. Here is the photo he posted.

- 399

 

[805 california]

All of this discussion about the sampler, the 'scope and the house AC service is nice, but I believe the reason the radio smoked was due to "HUMAN ERROR". When 805 repaired the burnt trace, he soldered the jumper to wrong place on the board. Here is the photo he posted.View attachment 18580

- 399

No I have the radio on now, nice try.

 

[805 california]

No I have the radio on now, nice try.

And I had the radio the radio running multiple times and when I would hook up to the scope it would start smoking. Did you read through the posts and see if got 24 volts DC on the chassis of the scope.

 

[Robb]

Unit_399 has a lot more experience with radios than I do!
I'd check that out - IMO . . .

 

[805 california]

All of this discussion about the sampler, the 'scope and the house AC service is nice, but I believe the reason the radio smoked was due to "HUMAN ERROR". When 805 repaired the burnt trace, he soldered the jumper to wrong place on the board. Here is the photo he posted.View attachment 18580

- 399

There is continutiy and those are grounds so it makes no difference.

 

[805 california]

Unit_399 has a lot more experience with radios than I do!
I'd check that out - IMO . . .

Well the jumper is still in place and it's not smoking. And I checked for continuity and it's working. Maybe 24 volts of DC on the scopes chassis might be the answer.

 

[357]

All of this discussion about the sampler, the 'scope and the house AC service is nice, but I believe the reason the radio smoked was due to "HUMAN ERROR". When 805 repaired the burnt trace, he soldered the jumper to wrong place on the board. Here is the photo he posted.View attachment 18580

- 399

I was just about to say....

 

[805 california]

Is the voltage just on the front panel or all of the exterior of the case?
Measure again with the volt meter set to AC volts.

The 24 dc volt is on any non painted metal like the carry handle and metal knobs and what now. And actually is fluctuating 36 volts.

 

[805 california]

Unless i missed it you never did say what the
end of the power cord for the scope has for a plug. Three pin grounded? Two pins with one blade wider than the other? Two pins both the same width? I just checked my Tektronix 465 scope and it has a three pin grounded plug. just wondering if yours has been replaced and possibly wired wrong by having the hot and neutral reversed.

Three pin cord

 

[805 california]

The 24 dc volt is on any non painted metal like the carry handle and metal knobs and what now. And actually is fluctuating 36 volts.

AC*

 

[222DBFL]

So you have 24-36 VAC or VDC floating on the chassis of the scope?? If so then I would about bet that your wiring is screwed in the scope or somewhere in your electrical wiring for the house. You have got a floating ground and you may get zapped messing about with the scope any further. Unplug it and have a person qualified to perform the work on the scope or at least have it looked at. Also check the house wiring at the breaker box and make sure that all breakers have a ground wire going to the breaker panel ground buss bar. Like CK said, AC power is not to be messed with!! It kills! Just be careful messing with the scope from here on out. Just some food for thought. Like I said, at this point I would not keep messing with the scope and also I would have an AC service tech come and cheek all your house wiring to make sure it's all up to code. JMHO's.

 

[805 california]

So you have 24-36 VAC or VDC floating on the chassis of the scope?? If so then I would about bet that your wiring is screwed in the scope or somewhere in your electrical wiring for the house. You have got a floating ground and you may get zapped messing about with the scope any further. Unplug it and have a person qualified to perform the work on the scope or at least have it looked at. Also check the house wiring at the breaker box and make sure that all breakers have a ground wire going to the breaker panel ground buss bar. Like CK said, AC power is not to be messed with!! It kills! Just be careful messing with the scope from here on out. Just some food for thought. Like I said, at this point I would not keep messing with the scope and also I would have an AC service tech come and cheek all your house wiring to make sure it's all up to code. JMHO's.

10-4 roger that. I got a really nice paper weight now.