04-30-2008, 01:08 AM
Hello Philco Fan! Dont know where everybody has disappeared to these days!? Congrats, on flyin-by-the-seat of your pants getting your Radiobar working again!! As far as tubes (pentagrid-converters types) such as 6A7s acting "flaky" when wiggling them around, here are a few suggestions to improve operations I always check closely.
(1)... make sure orig tube sockets arent broken(small intermittent shorts to chassis), then carefully clean inside the sockets female individual pin connections on the socket, and carefully "squeeze" each individual socket connection with needlenose pliers to make sure tube-pins are getting good connections once tube is installed in the socket. (tightening the connections on all tube sockets in the entire set is good practice also while tubes are removed)! You will find some "loose connections" indeed!!
(2).... make sure the tube-pin connections between base of tube and glass envelope are making good electronics connections thru the tube pins! I have found many "intermittent-shorts" in the tubes themselves because the small wires that terminate at the tips of the tube-base have a "cold solder joint". Scrape the old tube pin tips clean from tarnish, then carefully re-solder all the tube-pin connections by adding abit of new solder to each tube pin on the tube.
As you know, "flaky" pentagrid-converter tubes can really be critical in proper operation of any vintage radio. Whenever I get a "flaky" intermittent problem on these tubes, ( by wiggling them), and it interferes with sets operation, the prob can usually be found around the socket connections, or cold-solder joints in the tube pins.
(3)... make sure the pentagrid-converter tube has a tube-shield in place, (if needed and used as orig design). I have found many pentagrid-converter tubes missing orig tube-shields as needed on vintage sets discarded by previous hackers. Some vintage radios need-shields, some dont, but the tubes that "do", can be as touchy as a old-maid at a stags-convention indeed when "wiggling" occurs!!
(1)... make sure orig tube sockets arent broken(small intermittent shorts to chassis), then carefully clean inside the sockets female individual pin connections on the socket, and carefully "squeeze" each individual socket connection with needlenose pliers to make sure tube-pins are getting good connections once tube is installed in the socket. (tightening the connections on all tube sockets in the entire set is good practice also while tubes are removed)! You will find some "loose connections" indeed!!
(2).... make sure the tube-pin connections between base of tube and glass envelope are making good electronics connections thru the tube pins! I have found many "intermittent-shorts" in the tubes themselves because the small wires that terminate at the tips of the tube-base have a "cold solder joint". Scrape the old tube pin tips clean from tarnish, then carefully re-solder all the tube-pin connections by adding abit of new solder to each tube pin on the tube.
As you know, "flaky" pentagrid-converter tubes can really be critical in proper operation of any vintage radio. Whenever I get a "flaky" intermittent problem on these tubes, ( by wiggling them), and it interferes with sets operation, the prob can usually be found around the socket connections, or cold-solder joints in the tube pins.
(3)... make sure the pentagrid-converter tube has a tube-shield in place, (if needed and used as orig design). I have found many pentagrid-converter tubes missing orig tube-shields as needed on vintage sets discarded by previous hackers. Some vintage radios need-shields, some dont, but the tubes that "do", can be as touchy as a old-maid at a stags-convention indeed when "wiggling" occurs!!
