Are you testing if the switch works with a local broadcast, or one that is just barely able to be recieved? When I tweak a radio for sensitivity, I will tune to the extreme end of the dial and search for a station that is barely audible, but distinct; and those are usually about 600 miles away.
If that is the basic parameter that you are using and not noticing any differences between switch positions, but still pull those stations in well, it may be an issue with the AVC buss such as excessive leakage in the avc cap, or a bypass. Even new caps can sometimes be deffective. I would look at the one that "seems" to be working too, because the AVC would tend to mask whatever effect you might be getting from the different switch positions. Or maybe there is enough gain in the tubes to cover up the differences that you hear, or there is enough design variation between the radios themselves to produce the results that you see.
But I would first try for very distant stations. Usually this is best done after 9:00 PM central time, or later- Through to about 7:00am Central, as this corresponds to many stations that go to full power like KFAB, KOMA, KOXA, and others, and othe class B, C and D stations drop power output.
This is when you should really note differences.
: Hello,
:
: I have a couple Zenith AC-DC portable battery sets that have the three position switch on the chassis, which can be set for the best reception depending on wavemagnet postion -- in the cabinet, outside. Only one radio that I own with this feature seems to work as advertised. Both have been completely recapped and aligned and generally work swell.
:
: The switch is OK itself, I tried shorting that out to see if any change so it must be further upstream. Any ideas? Thank You.