Fourth in a vaguely defined series on obscure spy equipment.
This is a cross-pollination of 2 and 3. It’s another Peilempfänger by Telefunken, in the same modular miniature form as the Tenzor. Telefunken called it Kleinstpeilempfänger, which is bigger than the device. I’ll call it Minipeil for convenience.
Here Agent Polistra (with her Tenzor rig) has acquired a Minipeil and is equipping her pet alien to locate enemy transmitters. He’s not especially happy about the task. He’s carrying the tube-based radio across his belly “disguised” as a hearing aid, with the signal indicator “disguised” as a wristwatch. He would find the strongest signal by turning his whole body around while “checking the time”. Definitely inconspicuous!
Closeup of the receiver and the “watch”. No Telefunken colors this time, but a couple of neat Zenith-style gadgets. The tuning scale is printed on a removable cylinder which contains the coils for this band. Another ancient trick; pre-1920 radios often had a set of plug-in coils for different bands instead of a rotary switch. The center knob adjusts the antenna phase. Lower switch selects off or CW or AM. Thumbwheel on left is the tuning, and slides the cursor across the removable band-coil. Thumbwheel on right is volume.
The article at CryptoMuseum doesn’t give much detail. I’m guessing that most spies carried the Minipeil in a briefcase or purse, with wires up the sleeve to the “watch” on the other arm. The body mount would take some clever tailoring to hide effectively, unless the spy was fat or pregnant. A briefcase could be turned casually without attracting attention.