Here is a photo of some specialized Motorola items.
Many years ago Motorola produced a number of small individual boxes used to test various items. All the boxes were similar in appearance. One box had a meter and was used with a diode probe. Another was a pulse generator used to check low band radio noise blankers or as Motorola likes to call them Extenders. There were several other boxes produced for other applications. Shown below is a TEK 1A Tone Generator.
I have two of these Tone Generators. As a side note, the performances of both are a little disappointing. The frequency accuracy is not all that good and the distortion measured on the one above is 6.2% at the 1000Hz position and 2.3% at the 400 Hz position. The distortion was measured across a 1000 Ohm load. The performance must have been good enough for their intended use but it is a little puzzling why they did not finish the job and make the tone generator capable of producing a decent sign wave output.
Here is another box sample. This one is a TEK 20 PL Tone Generator.