Hi All,

I am a novice at radio repair. I have a Zenith 9 tube radio that plays great on SW across the dial but can only pick up one AM station very weakly. The tubes test good and the band switch has been cleaned and appears to be working. Where do I start? Thanks!

Hi Dana - I would check a couple of things - first, the
band selector switch could be dirty - get a spray can
of contact cleaner/lubricant from radio shack and see if
spraying the switch contacts while switching the switch
helps.

another possibility is that the radio needs alignment -
the tuning circuits need to be re-adjusted. if you're
a novice at this, I'd suggest getting help from someone
who has done this before.

good luck - Jim

: Hi All,

: I am a novice at radio repair. I have a Zenith 9 tube radio that plays great on SW across the dial but can only pick up one AM station very weakly. The tubes test good and the band switch has been cleaned and appears to be working. Where do I start? Thanks!

Hi, After making sure what jim said is done (he is right, rf is picky and doesnt like the tarnish that often forms on contacts),,if that's not it,
check the wires around the coils for shorts or breaks.
you may want to use a good length (25ft) or so of wire to generate a solid AM signal for testing..
Locate the compression cap either mounted above the Large variable tuning cap, or sometimes below chassis near the coils..
With the long antenna attached and tuned to your station, gently and slowly turn the compression screw or just rock it back and forth, noting it's original position.
Failing that, just tapping around while the radio is on with the butt end of a screwdriver is a low tech approch i use that often pinpoints problems with amazing reliability..
Make sure all your tube pins are clean, rough them a little with a fine emery board..

Sounds like your RF and audio chain is good, it's bound to be right up front..

: : Hi All,

: : I am a novice at radio repair. I have a Zenith 9 tube radio that plays great on SW across the dial but can only pick up one AM station very weakly. The tubes test good and the band switch has been cleaned and appears to be working. Where do I start? Thanks!

: Hi, After making sure what jim said is done (he is right, rf is picky and doesnt like the tarnish that often forms on contacts),,if that's not it,
: check the wires around the coils for shorts or breaks.
: you may want to use a good length (25ft) or so of wire to generate a solid AM signal for testing..
: Locate the compression cap either mounted above the Large variable tuning cap, or sometimes below chassis near the coils..
: With the long antenna attached and tuned to your station, gently and slowly turn the compression screw or just rock it back and forth, noting it's original position.
: Failing that, just tapping around while the radio is on with the butt end of a screwdriver is a low tech approch i use that often pinpoints problems with amazing reliability..
: Make sure all your tube pins are clean, rough them a little with a fine emery board..

: Sounds like your RF and audio chain is good, it's bound to be right up front..

Thinking about this some more, check the contact tabs on the bandsw..i have seen them bent or nearly worn out from use, ie, use a meter through it..it may look like it's contacting when actually it isnt..

Thanks ...will give those suggestions a try.