HeNe PSU repair.

[Morgan]

Hi All,

A while ago I received a non-special HeNe tube and brick PSU. All seemed to work fine. Tube sometimes didn't want to start but it was old and not that much of a surprise. Recently, however, I plugged it into a poorly wired socket which tripped out the house power circuits and I'm pretty sure popped the fuse in the wall plug, (UK 230VAC, fused plug). After replacing the fuse in the plug, the tube no longer fired up.

My question is; is there an internal fuse in the PSU itself and is it worth me opening it up to replace or simply replace the PSU?

I hope the attached photo shows the PSU clearly enough. It's the only photo I have at the minute.

I'd like to get this running to allow me to consider building an Argon alignment jig.

Thanks all,

M

 

[daguin]

Hi All,

A while ago I received a non-special HeNe tube and brick PSU. All seemed to work fine. Tube sometimes didn't want to start but it was old and not that much of a surprise. Recently, however, I plugged it into a poorly wired socket which tripped out the house power circuits and I'm pretty sure popped the fuse in the wall plug, (UK 230VAC, fused plug). After replacing the fuse in the plug, the tube no longer fired up.

My question is; is there an internal fuse in the PSU itself and is it worth me opening it up to replace or simply replace the PSU?

I hope the attached photo shows the PSU clearly enough. It's the only photo I have at the minute.

I'd like to get this running to allow me to consider building an Argon alignment jig.

Thanks all,

M

There is not a 'fuse" in the brick PSU, but there are some parts that can blow.

First, have you tested to see whether the PSU is still working? You said the tube had "trouble" starting. Maybe it has just gone over the edge.

Always test a component before working on it or replacing it. (No need to ask me how I know. )

Since the fuse in the plug blew, I would also test the plug, the wiring, and the wire-to-wire joints.

Have you tried it in a different socket? Maybe the socket didn't survive the short

If all the power to the PSU is good, but it is not putting out anything, my advice is simply look for a new one. Working inside them is a pain and based on your question, you do not appear to have much electronics knowledge.

Peace,
dave

 

[Morgan]

Thanks Dave,

I did test with another fuse and in another socket and nada.

I did think that the tube may just have passed on but I'm certain the PSU isn't putting out anything as there is no voltage to the tube. Primitive testing on that one but there was definitely no tingle!

The fuse in the plug was definitely toasted and this is why I'm confused the PSU is no longer working. As the fuse did blow, (3 or 5A I think), I would have thought it had done its job and protected the PSU? PSU blown, fuse blown and MCB tripping out seemed a bit odd?

Still, I will look for a new one and consider my options, (Maybe you are able to oblige?). I will dismantle it anyway as my electronics knowledge is improving all the time.

Thanks,

M

 

[roddenberry]

"brick" type power supplies unfortunately are composed of the main circuit board literally encased in epoxy, usually, when these go, there is no physical way to get access to the board, unless you use noxious "depotting" solvents that contains nasty stuff like tetrahydrofuran, acetone, and methylene chloride. That might melt the compound, as well as some of the components and part of your lungs...

If there are no voltage readings on your PS, I think it's toast and the easiest thing would be to buy another one. Oh and do salvage the big white HV alden plug, they're hard to find! There are chances the tube is still good.

- Robert

 

[Morgan]

I am feeling more and more resigned to the expensive of a new one. I hope I have learnt better wiring skills than my Dad considering his dodgey plug spur. I might just wire his lathe wrong in revenge! No, that'd be stupid. I want to use it too.

Thanks all, I'll be looking for a PSU if anyone sees one, (not the rarest of things so no-one go mad).

M

 

[diachi]

I have a HeNe with mount and PSU that you can have for £20 + postage. Leads on the PSU are a little short, but you can extend them or just make do as is. The mount has holes drilled for mounting, so you could incorporate that into your alignment jig?

 

[Morgan]

^PM sent Adam.

M