March 17, 2026 – Powering your radio (Battery or AC Power)

If you are using a mobile or base station radio an external power supply or battery is required. In recent years switching power supplies have taken over from linear supplies. Switching supplies are much lighter, smaller and cheaper but can cause noise especially on the HF bands. This is due to the fast switching rates that are part of the switching supply designs. This can be mitigated by adding filtering to the power supply to lower the noise generated internally. Linear power supplies do not have this issue and are inheritally noise free. The major disadvantage of linear supplies are their weight and low efficiency.

If you are planning on powering your 50 watt VHF or UHF mobile radio a power supply that can source at least 12 amps is recommended. Higher wattage base radios will of course require more current. Most dual band radios are only about 50 – 75% efficient when supplying 13.8 Vdc regulated power. Even better would be buying a power supply that can handle 22-30 amps at 13.8 Vdc in case you plan on upgrading to General and getting on HF with a 100 watt radio. Heavy 12 gauge wiring between the power supply and the radio is also recommended to keep the voltage drop low between the radio and the power supply when transmitting.

An external 12V battery may be used to power your handheld radio as well as your mobile or base station radio. The size of the battery needed is largely dependent on the power requirements of the radio and how long you need to maintain communications. A 20 amp-hr battery is large enough to power a handheld radio for several hours but won’t last long running 50 watts from a mobile radio. For longer operation time a 50 amp-hr or even a 100 amp-hr capacity battery is much better especially for emergency situations. The main two types of battery chemistry are lead-acid and lithium-iron phosphate batteries. Lead acid batteries have been around for well over 100 years and are relatively cheap but heavy. Lithium Iron Phophate, or LiPo batteries as they are known, are much lighter and maintain their output voltage much better that lead acid batteries. Each type of battery will require a different type of charger or a charger that can be set for both chemistrys. I would personally recommend a LiPo type of battery as prices have come down significantly.

If using a lead acid battery be careful where you place the battery and whether it is an AGM or wet cell battery. AGM batteries tend to be safer as they are sealed. Charging a lead acid wet cell battery should be done in a well ventilated room. No such precautions are needed for LiPo batteries and is another reason I recommend these types of batteries.

For further information check the internet or battery manufacturer.