Telex FM-1, QSB-1, SMP operating instructions Frequency Bands, Band Pairing for Systems

Section

8

Frequency Bands

Frequency Bands

The BTR-1 system operates in TV channels 16 to 36 and 38 to

59.This is the frequency range of 482 to 608 MHz and 614 MHz to 746 MHz. The band, the TV channels and frequencies are shown in Table 2. Most bands are 18 MHz wide, however band 7 is 24 MHz wide.

Bands F to E are always base transmit bands (beltpack receive bands). Bands 1-7 are always base receive bands (beltpack transmit bands). Thus an A2 base station would be comprised of an A band transmitter paired with a 2 band receiver.

Band Pairing for Systems

All band pairs cannot be made into a system (a single system is comprised of a base and beltpack). Table 1 show the avail- able band pairings.

Base TX Bands	Base RX Bands
F	1, 2, 3, 4, 5, 6, 7
H	1, 2, 3, 4, 5, 6, 7
A	2, 3, 4 ,5, 6 ,7
B	3, 4, 5, 6, 7
C	4, 5, 6, 7
D	5, 6, 7
E	6, 7

Table 1

Available Band Pairings

In Table 1 it can been seen that a C base station transmit band can be paired with 4, 5, 6 or 7 receive bands. However, a C3 unit cannot be made. This is because a certain amount of fre- quency separation between transmit and receive bands is re- quired for good transmit and receive operation. If they are too close the RF performance of the system is reduced.

Band	TV	Freq. Start	Freq. End
F	16	482	488
	17	488	494
	18	494	500
H	19	500	506
	20	506	512
	21	512	518
A	22	518	524
	23	523	530
	24	530	536
B	25	536	542
	26	542	548
	27	548	554
C	28	554	560
	29	560	566
	30	566	572
D	31	572	578
	32	578	584
	33	584	590
E	34	590	596
	35	596	602
	36	602	608
Not Used	37	608	614
1	38	614	620
	39	620	626
	40	626	632
2	41	632	638
	42	638	644
	43	644	650
3	44	650	656
	45	656	662
	46	662	668
4	47	668	674
	48	674	680
	49	680	686
5	50	686	692
	51	692	698
	52	698	704
6	53	704	710
	54	710	716
	55	716	722
7	56	722	728
	57	728	734
	58	734	740
	59	740	746

Table 2

Band Names and TV Channels

8-1