LEN BM 80(160) so-called. BULGARIAN
A general description of
Bulgarian radio station LEN BM 80, or BM 160 – generally called BULHAR. It works in the 80MHz band(160MHz). It is easy to retune to shared frequencies and conversions to the 2m FM amateur radio band are especially well-known.
Assumed frequency setting options, table with frequencies in the 70MHz band, Details about PLL settings and especially the complete diagram and layout of components can be found here: http://www.tenzor.cz/qwsaq/ham/bulhar/index.html
Diode matrix programming
The channels are programmed by soldering the diodes to the diode matrix on the board of the S41 block inside the radio station. Each channel frequency of the radio station is programmed by two rows of diodes separately for the receiver (series B) and separately for the transmitter (T series), since the synthesizer used has separate outputs for the receiver and for the transmitter. Each channel frequency has its own division coefficient different for the receiver Nr and different for the transmitter Nt. To calculate the coefficient we use the following formulas:
Coefficient calculation
Nr=fRX (kHz)-10700/12,5 Nt=fTX (kHz)/12,5
All information about diode matrix programming can be found here:http://www.progress1.kvalitne.cz/bulharprg.htm
Operating software for debugging
Properties resp. program options:
• Possibility to create your own list of frequencies.
• Automatic keying off (to prevent accidental keying)
• Two types of scanning. (frequency scanning and list scanning)
• Possibility to set various program functions
The program is not demanding on the system or on the PC. Works without problems on Win95,98 and XP. The connection to the station is made via a serial port. A detailed description together with the download program can be found here: http://www.sweb.cz/pajkadrak/programy/bulhar80/progbulhar.htm
73, Petr OK1RP
