Testing B+, Resistors, IF Cans

[cpacamper]

Hello folks,

I am new to old radios but have recapped a Zenith X337 from 1968 ( a great sounding little radio) and a much smaller aa5, a Zenith M504 am only radio from the mid-1960's I acquired to experiment with and learn on. Both were quite simple jobs. My knowledge of electronics is limited to what I remember from high school (very little), what I have read online, and in books such as "Fixing Up Nice Old Radios".

Since I am such a fresh newbie, my questions are pretty basic, but to me the answers will be very practical as I don't want to kill myself poking around the insides of 40-60 year old electrical equipment! Thanks for indulging me...

1. How does one test B+ voltage? I know one lead should be clipped to negative, ground I presume, and the other to various spots in the power supply circuit. Is ground a common ground such as a water pipe or is ground the chassis? In order to test B+, the radio should be plugged in and turned on? Also, if I want to test the voltages of the various tube filaments in series, I'd clip the red lead to the appropriate tune pin and black to ground (common or chassis?)?

2. On an ac-dc set, to test the chassis to see if it is hot, clip the red lead to the chassis and black to common ground such as a water pipe, turn on the set, then see if there is voltage? I realize there can be voltage with the set off as well and I have read the importance of using an isolation transformer.

3. On Photofacts for the 2 radios, I see charts for resistance measurements for various pins of tubes. These measurements should be taken with the radio off? Also, can accurate measurements of this type be made with typical Radio Shack analog multimeter (I've read where you need a VTVM for this)? Unless otherwise noted, the red lead of the meter is clipped to the indicated pin and black clipped to ground (again is it common ground such as a water pipe or to the chassis)?

4. On my little Zenith M504, I think there is silver migration problem with an IF can. Is there a measurement I can take to test the can before I try to pry it off the chassis and take it apart?

Many thanks in advance. I am learning and really appreciate any feedback you can offer.