5A anode current pulse, 11KV max anode voltage but only 15W anode dissipation
I guess that tells the story that it has ultra fast pulse capability! That and the -800V for cutoff suggest the currents going to scream skywards at every chance it gets
Its so easy to be wise afterwards - feel for you Paul... that was a real beast to get caught with!
On the subject of blowing up test kit - I've blown up an HP 4004 volt meter this afternoon...
I think its just a duff/end of life electrolytic - sure smells like one...
Ronald has given me a series of tests to do and report back to him. I am cooking now and have to go out for the evening also, tomorrow is a family day out.
As Ed says Oh waily waily. Not sure I spelled it correctly though.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
The "what has Paul done" head scratching is ongoing at Lab Ronald. Meanwhile I am sending him traces.
Ronald will be doing a write up of the specific situation, and testing the transistors which are damaged.
He is sending the necessary, but because I am an experimenter at heart and I had an MJE350 to hand I changed that alone. Did some tests and sent the results to Ronald.
One or more of the other transistors is affected, but there is an improvement in behaviour with the MJE350 changed.
I have no conscerns about the CV57 when you look at the job it, I can't see this event damaging it.
IT is hard to know where to go with the CV57. It says in the only information on the Web I can find, that it has the same type of box cathodes as the KT66. Perhaps this is where the valve supplier who was trying to offload them got the thought it was an "PX25 triode connected".
Well it clearly isn't, but I would like to see what it is like. We must need considerable negative bias before we find out.
Possibly with the uTracer on -50v and the anode limited to 100v and a current limit inline with the uTracer I can begin to edge up some information gathering slowly step by step.
Maybe if I find a quiescent point without runnaway I just hook it up and have a listen. All in the fullness of time.
Just buggs me to see such a beautiful valve never tried.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
Let me just say something here which is really important for us to take to heart.
Look at the fantastic after sales support we get here from Ronald.
This is where we in the West need to support people of similar background to us, instead of buying everything from emerging industrial revolution nations just because with their low labour rates and government support (which gives them an unfair advantage in our country, I can give you an example, when I did Solar PV the European manufacturers told me the certain country taking over the market are given a 20% premium by their own government for exporting to Europe[to counter VAT]) they have a 20% trade advantage.
I used to study Economics. This is disaster. Outr Western Governments must address this.
But the biggest issue for me is the after care. I guarantee it will be nill in such a case is the one documented here.
Similarly I recently bought a muse spdif converter it doesn't work to return it with proof of postage would cost me more than it is worth. OK a small thing. But he who can't be trusted in a small thing should not be trusted in a big thing.
So why say this?
I was considering importing a CNC coil winder from an emerging nation.
No thanks. Changed my mind. I would own a few grands worth of door stop as soon as the substandard design and production values reap fruit.
I'll just have to get my finger out and make my own. It is meant to be the first project after the uTracer.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
James wrote:Though I had referenced the uTracer heater circuit to the positive side of the filament, may not have though. Will check and re run during the week.
James.
Looks like my method was right.
I heat the dht's externally voltage devide to zero potential and connect this to the cathode uTracer post.
What is forbidden is using the internal heater on a dht and connecting that to the cathode connection. (which I would never consider doing) That is where the short circuit occurs which killed a whole uTracer.
"The situation is different when an external heater supply is used which is electrically floating with respect to the uTracer. In that case the cathode connection has to be connected to one of the heater connections on the tube (Fig. 23.2D). "
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein