Black Sabbath
New member
"OK, it happens to the best of us. If you tip or lean a tube a little too far you will hear a faint "snap" and then when you pull the tube out the central guide pin stays in the socket or drops into the amp. #!$!! Another scenario which is what we call a "noob incident" (we were all "noobs" at one time) when the "I GOT NEW TUBES!" adrenalin is pumping and you stuff the tubes in the sockets before even noticing that silly guide pin. Miss-indexing a power tube can cause some catastrophic results when the power is applied but some are lucky enough to miss-index a tube in the one or two positions that will cause no harm. Then when the amp does nothing and the tubes are removed the jammed in guide breaks off.
If you do break a guide pin then the tube is still usable as long as the glass is not physically broken. If this happens the silver getter flash in the top of the tube will turn white and it's game over. If the vacuum is still in tact then all you need to do is draw a line with a sharpie or white-out or even nail polish that runs up the side of the base of the tube so you can properly index or line up the tube with the timing notch in the socket. The first picture below shows a couple of "abused" tubes and the second shows a socket and the timing notch and the third with one of the abused tubes installed.
So carefully mark the tube to show where the timing key once pointed and then mark the chassis on your amp indicating where the timing key in the socket is pointing and carefully install the tube."
If you do break a guide pin then the tube is still usable as long as the glass is not physically broken. If this happens the silver getter flash in the top of the tube will turn white and it's game over. If the vacuum is still in tact then all you need to do is draw a line with a sharpie or white-out or even nail polish that runs up the side of the base of the tube so you can properly index or line up the tube with the timing notch in the socket. The first picture below shows a couple of "abused" tubes and the second shows a socket and the timing notch and the third with one of the abused tubes installed.
So carefully mark the tube to show where the timing key once pointed and then mark the chassis on your amp indicating where the timing key in the socket is pointing and carefully install the tube."
