Telex BTR-1 Frequency Bands, Band Pairing for Systems, Available Band Pairings

Section

10

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, 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 to 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

10-1