Hi, regarding vintage tube radios, am I correct in assuming part of restoration is cleaning tube pins and tube sockets in order to better electrical connections especially on the low voltage bias connections.

What I think I am seeing on my current project is a poor connection in my tube sockets as changing tubes makes a difference however readings are not consistence when I put the original tubes back in.

Also for those who have more experience then me, what is the probably that I may need to re-solder tube pins or should this be a standard practice.

Current project is a Zenith 6-S-229

Thanks
Larry Goldy

Larry: cleaning the tube pins and sockets is standard practice. Maybe use a contact cleaner along with a Q-Tip?

Shouldn't be necessary to automatically resolder connections to sockets. If there is a bad connection which you detect by visual inspection or wiggling, the you can remelt the connection and perhaps apply a little fresh solder.

Thanks Doug, I suppose my question was a little basic however I will add this part of cleaning to my routine. I didn’t think about wiggling the tube inside the tube socket to check electrical connections thanks, I will remember that. However on the tube pins themselves are they subject to internal oxidation causing poor continuity.

On rare occasion you will come across a tube with a loose pin lead. As Doug said, visually inspect pins, but don't automatically resolder. I had a 6K6G that would light up and then turn off occasionally. This was due to a loose filament lead. Sometimes tubes will do this when the filament is broken internally, too. The filament will heat up and then move due to thermal expansion. Then it'll go out. With filament trouble, suspect the filament, the tube pins, the socket, and the wiring under the chassis. If the tube doesn't go on and off in your tube tester, then you can narrow things down to the socket and associated wiring.

If you hear crackling noise in your speaker, this could be due to a loose grid or plate pin lead inside of the tube pins (suspect more than just the control grid when working with multi-grid tubes). It is more likely a faulty component such as a leaky and/or arcing condenser, or a faulty resistor (broken internally....possibly visibly cracked or charred)...maybe even the volume control. It could also be faulty chassis wiring or a fault in the power transformer, field coil, etc. It could even be a short between tube elements within the tube. The least likely cause would be a loose tube to pin wire. Check all items in the order which I have given them. If you haven't replaced condensers, then don't even think about tube pins unless one is obviously at fault--you can see the wire loose in the pin.

Though resoldering all of the tube pins is fairly easy, it usually is unnecessary. It ruins their appearance, as the original solder was buffed by some means to the nice round shape. With a glob of solder at the end of the pin, it'll make insertion of the tube into the socket difficult. Simply put, it's extra work that doesn't need to be done.

Thomas

Thanks Thomas,

Point well taken, I guess I was a little paranoid about good connections and will exhaust other avenues first before resorting to soldering tube pins.

Larry