04-27-2009, 12:09 AM
ahhh.. the wonderful loctal-socket syndrome strikes again! Sometimes, the loctal sockets are broken internally, between the wafers, that make contact from the tubes pins connections, to the solder pins under the sockets, not visible to the eye. To check for this, is by using your meter set to continuity. Find a small finish-nail that fits easily into the sockets pins connections of socket top-side of chassis,attach your meter leads to the socket individual solder connections under-chassis & finish nail top-side respectively for continuity check, and watch your meter as you move from pin-to-pin around the socket, while carefully "wiggling" the small (shiny clean steel type) finish nail. If a unknown invisible-internal socket pin "break" is located between the wafers, replace the entire socket. AES has replacements if needed. Ive run across several bad loctal sockets over the yrs! Intermittent only when you wiggle the tubes once installed. Very frustrating indeed! The old loctal sockets break (internally) easily, because of the force necessary for removal of the tubes in past servicing attempts. As for cleaning loctal tube pins, I carefully use a exacto-knife blade to scrape the pins to "shiny-clean" around the entire pins diameter. Even tho they look clean, try scraping them again!! If sockets show no signs of breakage, continuity good on all pins, spray a small amt of WD40 into the socket, re-install the tube, and remove it, repeat,re-install it several times, will help clean out debris & keep cleaned shiny tube pins from corroding again in the near future. Best of luck restoring your vintage Philco!