Baofeng UV-5R Portable Temporary GMRS Repeater - Part 1 - Operational Testing - Proof Of Concept

Portable GMRS repeater kit using two handheld VHF UHF dual band FM transceivers two-way radios. Temporary 70cm band UHF repeater 440 MHz repeater itinerant repeater 440.750 MHz 440.8 MHz (input +5 MHz). Concept applies to GMRS (Part 95 FCC rules) and amateur radio ham radio 70cm band 420-450 MHz band 432MHz band 440mhz band (Part 97 FCC rules).

Portable GMRS repeater 12-15 volt battery power emergency power or regular 110 volt AC 120VAC mains power supply with 12volt adapter and 110/120 volt AC or 220/240 volt AC to 13.8 volt DC 12VDC adapter and battery eliminator to convert it to 7.4 volts to power the two Baofeng UV-5R radios

   • Business Band Basics Part 2 UHF Itine...  

Temporary emergency repeater UHF 450-470 MHz GMRS radio repeater 462/467 MHz 462MHz also 420-450 MHz 440MHz band 70cm band repeater portable 70cm band repeaters 432MHz 420 MHz - 450 MHz 430-440 MHz 432-440 MHz



400-470 MHz
Inexpensive GMRS repeater. Portable GMRS radio repeater. Solar power or emergency powered repeater backup power EMCOMM GMRS repeater. True duplex repeater (well, semi-duplex, technically).

Build your own GMRS repeater

This is not a simplex repeater. This is a real simultaneous retransmission as it’s happening in real time duplex repeater with a split offset standard UHF + 5 MHz offset. Standard GMRS repeater channels GMRS repeater frequencies pairs.

GMRS repeater programming
How to use GMRS radio repeater
What is the difference between simplex repeater and duplex repeater

Half duplex vs. semi duplex
Full duplex
Simplex GMRS radio

List of FRS frequencies GMRS channels channel frequency chart

Radio A [receiver] listens to the repeater input frequency

Radio B [transmitter] transmits on the repeater output frequency

Each radio has its own antenna. Antennas are separated by height and horizontal distance.

Radio A and Radio B are linked via a repeater interface cable (interface box or repeater box)

For this demonstration, I used one of the 8 GMRS repeater channels (output is also used for GMRS simplex and FRS simplex, as are all the GMRS repeater outputs).

462.700 MHz - output 467.700 MHz - input

Standard GMRS repeater band plan. In accordance with FCC regulations.

There are 8 GMRS repeater pairs. The repeater input frequency (so what radios that are using the repeater TRANSMIT on) is always the output + 5 MHz. So 462.550 MHz + 5 MHz means the input is 467.550 MHz.

Portable, mobile radios and any radios using the repeater listen (receive) on the OUTPUT (462 MHz frequency) and transmit on the INPUT (467 MHz frequency). Most repeaters require use of a specific CTCSS tone (also called a PL tone or tone squelch tone) to “open” or “access” the repeater.

Remember that the 8 GMRS repeater output frequencies are shared with both licensed GMRS simplex users and unlicensed FRS users. They (the 462 MHz repeater outputs also are FRS channels 15 to 22. All users must share the 22 simplex frequencies. The 8 repeater input frequencies are for repeater input use only. SIMPLEX OPERATIONS ARE NOT ALLOWED ON THE DESIGNATED GMRS REPEATER INPUT FREQUENCIES.

462.5500 MHz pair - FRS channel 15 (output)
462.550 MHz - repeater output
467.550 MHz - repeater input


462.5750 MHz pair - FRS channel 16 (output)
462.575 MHz - repeater output
467.575 MHz - repeater input


462.6000 MHz pair - FRS channel 17 (output)
462.600 MHz - repeater output
467.600 MHz - repeater input


462.6250 MHz pair - FRS channel 18 (output)
462.625 MHz - repeater output
467.625 MHz - repeater input


462.6500 MHz pair - FRS channel 19 (output)
462.650 MHz - repeater output
467.650 MHz - repeater input


462.6750 MHz pair - FRS channel 20 (output)
462.6750 MHz - repeater output
467.6750 MHz - repeater input


462.7000 MHz pair - FRS channel 21 (output)
462.700 MHz - repeater output
467.700 MHz - repeater input


462.7250 MHz pair - FRS channel 22 (output)
462.725 MHz - repeater output
467.725 MHz - repeater input


This example is using GMRS 700 or 462.7 MHz

462.700MHz output 462.70000 FM
100.0 Hz PL tone squelch transmit and receive
T-CTCS 100.0Hz
R-CTCS 100.0Hz



Non-standard - GMRS radio tone. Recommended tone is 141.3 Hz PL 141.3 also known as the “Travel Tone”. Use of 141.3 Hz is strongly recommended on the GMRS calling channel 462.675 MHz simplex - this is the same as FRS channel 20.

70CM band portable repeater temporary repeater special event emergency communications ARES RACES

440.750 MHz output 445.750 MHz input
440.800 MHz output 445.800 MHz input

Band plan cross-band repeat 144MHz band plan 440MHz band plan 29MHz band 222MHz band plan 902-928MHz band plan 902.500 MHz 927.500 MHz 915MHz

462.5625 MHz
462.5875 MHz
462.6125 MHz
462.6375 MHz
462.6625 MHz
462.6875 MHz
462.7125 MHz
467.5625 MHz
467.5875 MHz
467.6125 MHz
467.6375 MHz
467.6625 MHz
467.6875 MHz
467.7125 MHz
462.5500 MHz
462.5750 MHz
462.6000 MHz
462.6250 MHz
462.6500 MHz
462.6750 MHz
462.7000 MHz
462.7250 MHz