06-07-2018, 06:43 PM
resto in work and so today for a little bit i swapped out one capacitor at at time.,, then verifying the unit still works and moving on.
towards the end of the cap replacement i took a phone call while the radio was playing.
suddenly the speaker noise went quite so... i raced over to the work bench and turned it off and unplugged the radio.
the last two caps i was dealing with were tied to the antenna terminals both "ANT" and "GND".
the "ANT" terminal had what appears originally as a .1MFD cap. the diagram showed a .01 MFD.,, which leads to the designated "T1".
I decided to install a .01MFD cap for the ANT ckt to match the diagram.
the antenna "GND" had an original .01MFD cap in i replace it with the same value.
when my Minerva unit speaker when quiet, i powered down but soon powered back up to see if i could finish off any resistor that was letting out the magic smoke... in other words see if the radio could show me where it is broke. Nothing,, all is well ,, just no sound.
at this point i all i can tell is that both my 6SK7's are barely getting above room temp but they are not lighting up nor getting anywhere hot,, they do seem to get a tiny bit "warm". I traded thier spots to see if it was just one bad tube but still no luck.
the nostalgia air diagram includes two prints,, my model is the top print "model w117 early" from what i can gather now that i have compared all the caps and a few resistors.
i have no 6sk7's avail,,, i have 6sc7's though but i dont think they will work.
attached is the schematic i am using.
does anyone think my antenna capacitor is wrong? and could it be causing this? i highly doubt it myself but just asking.
this is one of those typical "it was just working" situations,, im sure we all have been here before.
towards the end of the cap replacement i took a phone call while the radio was playing.
suddenly the speaker noise went quite so... i raced over to the work bench and turned it off and unplugged the radio.
the last two caps i was dealing with were tied to the antenna terminals both "ANT" and "GND".
the "ANT" terminal had what appears originally as a .1MFD cap. the diagram showed a .01 MFD.,, which leads to the designated "T1".
I decided to install a .01MFD cap for the ANT ckt to match the diagram.
the antenna "GND" had an original .01MFD cap in i replace it with the same value.
when my Minerva unit speaker when quiet, i powered down but soon powered back up to see if i could finish off any resistor that was letting out the magic smoke... in other words see if the radio could show me where it is broke. Nothing,, all is well ,, just no sound.
at this point i all i can tell is that both my 6SK7's are barely getting above room temp but they are not lighting up nor getting anywhere hot,, they do seem to get a tiny bit "warm". I traded thier spots to see if it was just one bad tube but still no luck.
the nostalgia air diagram includes two prints,, my model is the top print "model w117 early" from what i can gather now that i have compared all the caps and a few resistors.
i have no 6sk7's avail,,, i have 6sc7's though but i dont think they will work.
attached is the schematic i am using.
does anyone think my antenna capacitor is wrong? and could it be causing this? i highly doubt it myself but just asking.
this is one of those typical "it was just working" situations,, im sure we all have been here before.
