HRO Coils

HRO Coils

HRO Coil Ranges

CoilGeneral Coverage RangeBandspread Range
A14.0-30.0MHz28.0-30.0MHz
B7-14.4MHz14.0-14.4MHz
C3.5-7.4MHz7.0-7.4MHz
D1.7-4.0MHz3.5-4.0MHz
E900-2050KHz
F500-1000KHz
G175-400KHz
H100-200KHz
J50-100KHz
JA14.0-30.0MHz
JB7-14.4MHzMHz
JC3.5-7.4MHz
JD1.7-4.0MHz


Pre HRO-50 Bandspread vs General Coverage Setting

Inspection of the bandspreadable coil terminal panels will show several small rectangular metal pieces. There are two of these pieces or terminal blocks on each of the coil panels that are threaded. A small flathead machine screw will be found in the right or left hand threaded terminal block of each coil. With the screws in the left hand positions, looking at the assembly from the top/front, the coil range will be that shown in the left hand, or general coveral, chart. If it is desired to change the calibration to amateur bandspread, as shown in the right hand chart, it is only necessary to move the four screws to the right hand threaded terminal block of each coil.


HRO Coil Identification

To positively identify an orphan set of HRO coils, inspect the coil housings. Each housing should have a designation in the form of letter-number stamped on the terminal panels. The letter corresponds to the band letter. The numbers 1 through 4 designate coils for the SR/M/5/7 series while numbers 5 through 8 designate coils for the RAS. For example, the HF Osc coil for an RAS Band 5 (or C) coil set is stamped "C8". This 1st RF coil for an HRO Band B coil set is stamped "B1".



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