Original Polish version by Lukasz Kopciuch

GSM repeaters
![]() GSM repeater Signal GSM-305 A6765 | ![]() GSM repeater Signal GSM-505 A6775 | ![]() GSM repeater Signal GSM-1205 A6785 |
Name | Repeater SIGNAL GSM-305 | Repeater SIGNAL GSM-505 | Repeater SIGNAL GSM-1205 |
Code | A6765 | A6775 | A6785 |
Operating bands [MHz] | 880-915 925-960 GSM+EGSM | 880-915 925-960 GSM+EGSM | 880-915 925-960 GSM+EGSM |
Output power [dBm] | 10 | 15 | 20 |
Gain [dB] UP/DL | 60/60 | 65/65 | 70/70 |
Max group delay [ μs] | 0.5 | 0.5 | 0.5 |
Input attenuation (adj. manually) [dB] | 0-31 (step 1) | 0-31 (step 1) | 0-31 (step 1) |
AGC range [dB] | up to 20 | up to 20 | up to 20 |
Indoor coverage area [m2] | 300 | 500 | 1200 |
Impedance [Ω] | 50 | 50 | 50 |
Certificates | CE (ETSI 300 609 -4), RoHS | CE (ETSI 300 609 -4), RoHS | CE (ETSI 300 609 -4), RoHS |
Dimensions [mm] | 218x155x65 | 218x155x65 | 218x155x65 |
Antenna connectors (for outdoor/indoor antenna) | N-f/N-f | N-f/N-f | N-f/N-f |
The new GSM amplifiers/repeaters from Signal series can be used
in all GSM networks
in all GSM networks
- Extended operating band
The appearance of additional frequency ranges (880-890 MHz, 925-935 MHz), extending the existing GSM900 band (890-915 MHz, 935-960 MHz) aims to increase competition in the market by assigning "new" frequencies to new mobile operators. The new band is called EGSM - Extended GSM.
The lack of the new GSM band (880-890 MHz, 925-935 MHz) in GSM repeaters/amplifiers would eliminate the possibility of using cellular phones of the new operators (in the areas/buildings/rooms that do not guarantee proper connectivity without such boosters).
- Some cellular networks using EGSM band:
- Poland:
- Play
- Aero2
- Austria
- One GmbH
- Belgium
- Base
- Bulgaria
- BTC Mobile EOOD
- Czech republik
- Telefónica O2
- Denmark
- Telia Nättjänster Norden AB
- Estonia
- EMT AS
- Elisa Mobiilsideteen-used AS
- Tele2 Eesiti AS
- Holland
- Orange
- Telfort
- Finland
- Radiolinja Origo Oy
- Sonera Mobile Networks Oy
- DNA verkot Oy
- France
- Bouygues Telecom
- Deutchland
- E-PlusMobilfunk GmbH & Co KG
- O2 (Germany) GmbH & Co OHG
- Italy
- TIM
- Liechtenstein
- Orange
- Lithuania
- Omnitel
- Bite Litetuva
- Tele2
- Luxembourg
- VoxMobile SA
- Moldova
- Eventis Mobile SA
- Romania
- Cosmote RMT
- Slovakia
- Telefonica O2
- Spain
- Telefonica Moviles
- Orange
- Swiss
- TDC
- Orange
- Great Britain
- 02
- Vodafone
- To avoid such problems, DIPOL has introduced new GSM amplifiers that amplify the whole GSM and EGSM (880-915 MHz, 925-960 MHz) bands.
GSM band consists of 124 channels, each 200 kHz wide. The channels are numbered from 1 to 124. The center frequency fn of n channel is determined by the formulas: for "upper" channels" fn= (890 + n*0.2) MHz, for "lower" channels fn=(935 + n*0.2) MHz.
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 |
21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 |
41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 |
61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 | 73 | 74 | 75 | 76 | 77 | 78 | 79 | 80 |
81 | 82 | 83 | 84 | 85 | 86 | 87 | 88 | 89 | 90 | 91 | 92 | 93 | 94 | 95 | 96 | 97 | 98 | 99 | 100 |
101 | 102 | 103 | 104 | 105 | 106 | 107 | 108 | 109 | 110 | 111 | 112 | 113 | 114 | 115 | 116 | 117 | 118 | 119 | 120 |
121 | 122 | 123 | 124 |
GSM channels
EGSM, which uses 880-890 MHz and 925-935 MHz frequency ranges, includes additional 50 channels. They are numbered from 975 to 1023 according to the formula fn=[890+(n-1024)*0.2] MHz and fn=[935+(n-1024)*0.2] MHz, where fn is the center frequency of channel n (each 0.2 MHz wide).
975 | 976 | 977 | 978 | 979 | 980 | 981 | 982 | 983 | 984 | 985 | 986 | 987 | 988 | 989 | 990 | 991 | 992 | 993 | 994 |
995 | 996 | 997 | 998 | 999 | 1000 | 1001 | 1002 | 1003 | 1004 | 1005 | 1006 | 1007 | 1008 | 1009 | 1010 | 1011 | 1012 | 1013 | 1014 |
1015 | 1016 | 1017 | 1018 | 1019 | 1020 | 1021 | 1022 | 1023 | 1024 | 1025 | 1026 | 1027 | 1028 | 1029 | 1030 | 1031 | 1032 | 1033 | 1034 |
EGSM channels
- Compliance with ETSI 300 609-4

Recently, European countries have tightened the regulations applicable to some wireless telecommunications equipment. Currently, in order to distribute GSM repeaters in EU countries as lawful merchandise, the manufacturer or distributor has to put them through testing procedures in appropriate laboratory, to confirm compliance with the following standards:
Radio equipment launched on the market from June 13, 2016 to June 12, 2017 should meet the requirements of Directive 2014/53/EU or Directive 1999/5/EC. After June 12, 2017, all radio equipment being placed on the market or put into service must comply with the Directive 2014/53/EU
Currently, the equipment must be tested for compliance with the following standards:
- ETSI EN 300 609-4 V8.0.2 (The most important) Digital cellular telecommunications system (Phase 2 and Phase 2+); Base Station System (BSS) equipment specification; Part 4: Repeaters (GSM 11.26 version 8.0.2 Release 1999).
- EN 60950-1:2004-. Security.
- ETSI EN 301 489-1 V1.6.1 Electromagnetic compatibility and Radio Spectrum Matters (ERM); Electromagnetic Compatibility (EMC) standard for radio equipment and services; Part 1: Common technical requirements.
- ETSI EN 301 489-8 V1.2.1 Electromagnetic compatibility and Radio spectrum Matters (ERM); Electromagnetic Compatibility (EMC) standard for radio equipment and services; Part 8: Specific conditions for GSM base stations.
- ETSI EN 301 502 V8.1.2 Harmonized EN for Global System for Mobile communications (GSM); Base Station and Repeater equipment covering essential requirements under article 3.2 of the R&TTE directive (GSM 13.21 version 8.1.2 Release 1999).
The certification evidence of compliance with European Union regulations issued by the laboratory has to encompass all the above mentioned standards. The same applies to CE declaration of conformity issued by the manufacturer or importer. There are also declarations of conformity with the harmonized standards of R&TTE Directive, but the distributor must be sure that the standards are contained in this directive.
- Adjustable input attenuation
A serious problem during the installation of a GSM repeater is to ensure adequate signal level at the input of the amplifier. In the case of too weak or too strong signal, the system will not function properly (broken calls, problems to establish connections etc.).
A convenient solution to this problem provides the built-in attenuator allowing to adjust the level of the input signal (attenuation 0-31 dB, step 1 dB). The approximate signal level is indicated by LEDs located on the front panel of the repeater.

- Automatic Gain Control (AGC)
As mentioned above, the input signal level is essential for stable operation of GSM repeaters. Of course, it can be adjusted manually when installing the system, but later, when a cellular operator increases output power of its base station, changes the transceiver or antenna, deploys a new base station etc, it would require another visit of the installer.
To avoid this problem, the Signal repeaters distributed by DIPOL have been equipped with automatic gain control, which keeps the output signal level stable irrespective of the input changes within 20 dBm range.