UrS,

Inspite of the natural number sequence :
2200 2600 2800 2900
..
The Pansonic RF Series of Radios came out :
RF-2200 RF-2800 RF-2900 RF-2600
..
The RF-2600 was the last (best?) of the Panasonic
'portable' AM/FM Shortwave Radios that had Analog
Tuning with a Digital [Frequency Counter] Read-Out.
..
hth ~ RHF