Why is the CRT taking longer to light up?

[Tubejunke]

Originally Posted by Magnavox300

Thanks for all the replies,
after tapping on a few things in the back,
the screen now comes up right away...
Not sure what it was, maybe the CRT plug as Tubejunke thought,
though it was on tight. Magnavox300

This may have been one of the most valuable lessons that you will learn in this hobby, and frankly I think you learned it the easiest way; with a c.r.t. I say this because with a c.r.t. you get to see the fix on the screen. Tubes have a pretty big design flaw being pins and sockets made of varying qualities of metal, most of which oxidizes over time.

Everything can appear to be "tight" and is in many cases like this where the plastic locating plug is the primary anchoring point. Meanwhile you have electronic connections often marginal at best or even open as would be the case here with the final possibility of voltage dropped to a point so low as to not be able to rated potential.

With any tube equipment it is essential to get a cleaner for electronic parts and go through all tubes cleaning the tubes and the sockets. They used to make cleaners especially for this along with tuner contact cleaner which worked just as well like DeOxit and such. The trick is to take an old pocket knife or what have you and scrape the tube pins until they shine. It's not hard; just a few swipes and you can often cover more than one pin at a time. Spray the socket and insert, remove and reinsert the tube several times to help clean the socket. You will be much less haunted with misguided troubleshooting this way. Hope this helps!

[Magnavox300]

Originally Posted by Tubejunke

This may have been one of the most valuable lessons that you will learn in this hobby, and frankly I think you learned it the easiest way; with a c.r.t. I say this because with a c.r.t. you get to see the fix on the screen. Tubes have a pretty big design flaw being pins and sockets made of varying qualities of metal, most of which oxidizes over time.

Everything can appear to be "tight" and is in many cases like this where the plastic locating plug is the primary anchoring point. Meanwhile you have electronic connections often marginal at best or even open as would be the case here with the final possibility of voltage dropped to a point so low as to not be able to rated potential.

With any tube equipment it is essential to get a cleaner for electronic parts and go through all tubes cleaning the tubes and the sockets. They used to make cleaners especially for this along with tuner contact cleaner which worked just as well like DeOxit and such. The trick is to take an old pocket knife or what have you and scrape the tube pins until they shine. It's not hard; just a few swipes and you can often cover more than one pin at a time. Spray the socket and insert, remove and reinsert the tube several times to help clean the socket. You will be much less haunted with misguided troubleshooting this way. Hope this helps!

Thanks, good advise!
I think I'll take an hour and clean the tube pins, and sockets with Deoxit...
I remember once reading you shouldn't scratch the tube pins, since they are coated? I would rather go with your suggestion, and get them bright again and not worry about it, I'd rather have a good connection...
You said use a pocket knife or something and scrape them till they shine,
are you sure that's okay to do?

[Tubejunke]

Originally Posted by Magnavox300

I remember once reading you shouldn't scratch the tube pins, since they are coated? I would rather go with your suggestion, and get them bright again and not worry about it, I'd rather have a good connection...
You said use a pocket knife or something and scrape them till they shine,
are you sure that's okay to do?

I think my reply is a little late in the game and you have probably already done the right thing. Actually, I found it interesting that you stated that you read that the tube pins were somehow coated. I'm not saying that there is no truth to that; maybe some special applications or something, but I have never heard of any coating. If they did coat them with say some conductive anti-oxidant or something, then it didn't work. Gold would be the way to go, but counter cost effective. Silver is the best conductor, but it tarnishes which would give us what we have. The pocket knife (cheap) or whatever implement you use to me is one of your most valuable service tools; right up there with your V,O.M.

Also, I think the topic of pins being delicate came up and someone correctly put any fears there at ease. In fact, they are very rugged in my experience. Even the small pins on say a seven pin miniature can be bent and straightened a number of times without issue. Actually, I have never broken one. The most likely to break would be something like an octal, and they would break from the plastic base. C.R.T. pins have a bad habit of needing to be re-soldering once the epoxy (or whatever glue they used) gives out and the plug is left supported by the wires protruding from the glass.