I went to the yard sale looking for two items and found both of them in great shape.
First was a Triplett 630-A multimeter. These date back to the 1950's and were the go-to standard for benchtop multimeters. I sold mine when I moved from Boston to Seattle and always regretted it. They require an odd 30 volt battery but there are workarounds using three 9-volt radio batteries (27 volts is close enough).
Second was a Heathkit HD-1250 solid-state dip meter. You use plug-in coils to provide a wide range of frequencies from 1 million cycles per second or Megahertz all the way up to 250 MHz. 90% of the amateur radio frequencies lay within this range. The frequency is generated by a simple oscillator and when the unit is brought near to something that is resonant on the same frequency, power is transferred. I can rock the tuning dial back and forth, notice where the peak power transfer is and that is the resonant frequency of the object I am testing. I already have something that does this automatically for antennas but it only works for fully completed antenna systems and not for individual components. If I need to make a coil for a given frequency, I can calculate what I need, wind about 10% more turns and then gradually use wire clippers to nibble the coil down to my desired frequency. Not something I will be using every day but when you do need it, it is invaluable.
All in all, a great score. Ran into a bunch of friends at the event - probably about 20 people picking over a very large pile of junk collectibles. The museum is an amazing resource for Bellingham and an incredible collection of electricity, radio and television history.
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