Thanks again for all your comments.I guess I can't reverse what I said on eBay remarks . I did leave positive feedback because it was too difficult to leave a neutral one. The rest I gave a one star rating to. Because there was non lower.
Ian,the plumbicons came up very well. I cannot remember the tube type they were one inch, used in the Phillips LDK25 cameras.
I do not know what I did with those rejuvenators I made several I wish I still had them. I guess I could make another, I full wave rectified the mains and filtered it and had a push button in series with the output volts. It was so long ago I can't remember where I applied it .
I think it was negative to the cathode and the 300+ volts onto grid one. Used to give them 2 or 3 quick bursts on the button and look at all the pretty sparks. I never blew any up. I often wondered how they would work on radio valves anyone up for a chalange?
I would imagine many of you have used them to rejuvenate your picture tubes.

Silicon Diodes and non sleeved feeding heater tubes are the most likely to need 630V caps. This, as they create a surge that can be close to twice EMF, before getting any significant current flow, prior to the heaters causing conduction & dragging it down.

Heater rectifiers don't do that, so you can get away with 400V, or less on a set that runs 250V loaded side.

The Russian 5Y3 is ruggedised and has a massive filament, it is built more like the 6X.. series and has from my experience with them, a cathode sleeve. It does not produce anywhere near the same surge.

Marc

Yes Jim , You can Edit what you wrote in the feed back ,Sometimes sellers send a link asking you to edit it , But you know mate ,Dont lose any sleep about ,,Its just Ebay at the end of the day and as you said you left a positive ....Pete

Pete I messaged them and asked them to send me a feedback review request. I don't like doing the wrong thing by people .
I looked on the net first and could not find any information on them . However Ian found it . I just could not see how these piddley little caps could have such high rating. If I use them I will be very cautious where I use them. I was just trying to conserve my dwindling supplies and thought I would give them a try. I still have enough of the good caps for the time being and will order more before I run out.
I was too ready to lash out after my last few experiences .

Getting back to my tube blasting I am sure I was correct negative to cathode and a big fat plus on grid one, to blast the crap off the cathode It was a common practice back in my TV repair days as a young bloke I am sure many of you did the same.
That was half a lifetime ago.
Regards Jim

They are good caps Jim, use them without a worry.

You could always wire them in, face the chassis away from you and apply power. If they come flying out in pieces you'll know why.

Now some toys are handy. I built an electrolytic capacitor "reformer" onto the end of the bench PSU. It steps from 25V to 400V. Its main purpose is to weed out the new duds that occasionally turn up, & making sure that the ones that have been sitting a while get refreshed before use.

Of course that could be used in a pinch as a leakage / voltage tester for NP ones, however there are other devices on hand here, for that, Both insulation testers are good for 1000V one has four steps & can go lower and the ageing valve & circuit tester has provision for valve radio caps.

That all saves putting them in radios & have them do damage. If you think it has potential to explode: Bund it in a bit of plastic conduit.

The reformer has an LR8 regulator which will lock up if the current is excessive. That makes it ideal for externally powering "B" when you think you have a dud cap and there is no voltage divider: It would need disconnecting. One does not power the heaters, or the set by any other means other than the reformer for this exercise.

Failure of new caps is rare & it won't get into the set it you reform it first. Really old Ecaps, one replaces not reforms. Often the dud Ecap will reach a voltage (below rated) and then start conducting at a hyperbolic rate. It should be noted for the unaware, that Electrolytic caps are chemical & rely on an oxide layer for insulation. That requires a current to pass through them to maintain the oxide layer and it will gradually deteriorate with no power.

This is why you never power a set with electrolytic caps, after it has been sitting unused for years. They are liable to explode OR present as a short circuit and do some expensive damage.

Thank you all again for your comments I always take on board what is said .
Kind Regards. Jim

I've just bought a small number of greencaps from Jaycar. They are shown as having a 100-=volt rating. I hope I can trust this?
John

Yes John 100v greencaps are reliable unless you exceed the voltage rating. Fine in valve radios for AGC bypasses and the like. They do have a small temp coefficient like most (but not all) plastic caps so don't use them in TV hor osc tuned circuits for example.

Thank you Ian🙂