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Excellent information Todd.
I own the following portable radios:
Panasonic DR-22 (Australian version of the RF-2200).
Tandy Realistic TRF radio.
Tecsun PL-380 / 390.
Sangean PR-D3 (Australian version of the Crane CC 2E).
My Panasonic DR-22, and Realistic TRF radios are insensitive compared to the other Tecsun and Sangean radios. Moreover, I don't bother using any radio that doesn't feature digital frequency readout to minimum 1 KHz steps. They are both packed away in storage.
My favourite radio for general MW DX reception from home is the Sangean PR-D3. When used 'barefoot' it is the most sensitive of all six radios. From a single 5 inch diameter speaker, it produces the best overall audio fidelity. As expected the CC Crane 2E reportedly also sounds excellent. The 200 mm length internal ferrite rod couples well to external air core loops. It features nominal 6 KHz wide, and 3 KHz narrow bandwidths. The SiLab 4734 3 KHz narrow bandwidth setting improves weak signal S/N. Narrow bandwidth also assists when peaking loop antenna. Optimal inductive signal pickup is when the radio is placed to the side centre of an air core loop. It doesn't suffer from any overload in my city area. Selectivity is good, but not as good as the PR-D15.
My next MW favourite is the Sangean PR-D15. Its main attribute is high MW selectivity when attempting to receive split channels (e.g. weak 1580 KBLA California next to strong Australian 1584 KHz), or a 9 KHz weak signal adjacent to a strong local. Selectivity is better than all six radios. SiLab 4731 chip default selectivity is ~ 4 KHz. The 200 mm length internal ferrite rod couples well to external air core loops. Fair audio quality. Optimal inductive signal pickup is when the radio is placed to the side centre of an air core loop. Signal overload rejection is better than all six radios.
Tecsun PL-380 / 390 are mainly used for their excellent digital signal strength meter. Potential applications include determining relative ambient RF noise on blank channels. Internally generated spurious hets are a disadvantage unique to these two radios. None of the other four radios generate signal spurs. Audio quality via the speaker is arguably relatively poor. Quality headphones would improve this. Shorter length internal ferrite rod inductive signal coupling is fair to air core loops.
The most sensitive radio: Sangean PR-D3.
The most selective radio: Sangean PR-D15.
Paul - Moderator