blown caps for fta receiver

[AcWxRadar]

That could still leave the guy behind the 'scope floating at 110v.
Not a situation I'd put a neophyte in.

The first rule of working on line-powered switchers, is to run it on a reliable isolation transformer.
As there might still be leakage, I use two robust 24v transformers, back to back.

I'm all for giving tricks to the newbies, but not if it might kill a stupid one.
And when it comes to strangers on a forum, ya just can't tell.


edit:
Oh, you might be right!
And that makes my point!

Anole,

You are definitely correct. I also use an isolation transformer, but failed to mention so. The iso transformer I have is a manufactured one that I got from work as salvage. I use the 3-prong to 2-prong adapter plug on its cord to ensure that earth ground isn't tied in there somewhere. I should have been more specific.

EDIT: May I add that I also did not expect Fhorta to rush right out and buy an O'scope for this task nor did I expect that he already owned one. Therefore the situation is moot other than the learning that was gained by all. I don't wish to withold information, but I don't want to sacrifice anyone's personal safety either. I know that you believe me in this regard, but I should have explained it in detail right off.

RADAR

 

[AcWxRadar]

The main thing here is if he's not sure what needs to be done then check everything without power or find someone to help.

Now I will say that when working on computer mainframes and the drives we did remove the ground which was common practices for working on the equipment and that included all types of devices.

To help others understand using a scope and this issue check out this link as some might find it interesting.

[h=3]Oscilloscope operation differential voltage measurement[/h]http://www.youtube.com/watch?v=VWodjUSkYVE

Sergei,

The video you posted is the best (safest) method. Rules out the earth ground/neutral leg connection and still provides the o'scope view of the signal where you can see, in real time, what is really happening with your circuit or across any load. Totally safe. It is a most excellent method to accomplish the troubleshooting that is required. I would still recommend the isolation Xfrmr and no earth ground in conjunction with the ADD/Invert mode on the scope and remove the ground clips from the leads/probes.

EDIT: I must add that these are the discussions which are most beneficial. Regardless of the negative comments that occurred, this thread has brought us to some very important information that is valuable to everyone and that is POSITIVE! It is occasions such as this which make me very proud to be among this group and be able to discuss troubleshooting practices in this way. I believe that we are here and this forum is here to educate and learn. I learned from this experience and I beliwve that other's did as well. Expressly FHorta. I hope that he has discovered his error and knows for the future what to look for and where to get answers. It's just a win-win situation when we all put our thoughts together and critique every item and discuss them all openly.

RADAR

 

[fhorta]

Hello all. I do.apologize for flaming . I know there lots of members here with plenty of knowledge.and experience. Well, thanks to your help I was able to replace capacitors the right way this time, negative and positives sides how they should.be. caps are ok after receiver has been connected for well over an hour. Receiver powers up, goes on standby, channels, the whole nine, but still no signal or quality....again, any help is appreciated. I know I had posted that I might have damaged my rectifier in a previous post but being that receiver operates fine except for.signal and quality issues would that still be the case? Thanks again.

edit: added an image of the board i'm working with. the 3 caps i replaced are at top right hand corner .