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Portable Operation Battery and XCVR Protection

Sep 8th 2015, 18:53

DV1UBY

Joined: Jan 3rd 2015, 19:35
Total Topics: 0
Total Posts: 0
I would like to know what kind of telecoms battery for radio operation such as HF transceivers? I'm planning to operate in portable or stationary station. Also, I want to protect my XCVR from battery power surge. Please advise. Thanks.
Sep 8th 2015, 19:53

W1VT

Super Moderator

Joined: Apr 4th 1998, 00:00
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Normally one has to compromise for HF--it takes a very heavy battery to power a 100W station, so many stations will run less power reduced power, such as 25 watts, to allow a reasonably sized battery to power the station. Alternately, gas generators are often used when one needs to run 100 watts or more. There typically isn't an surge issue from batteries.

Zack W1VT
Sep 11th 2015, 01:37

AI4BJ

Joined: Sep 2nd 2003, 12:14
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Total Posts: 0
SLA (sealed lead-acid) batteries come in many different sizes, are relatively inexpensive, but very heavy. LiFePO4 (lithium iron-phosphate) batteries have a much higher energy density and have a longer life than SLA batteries, but cost more. As Zack states, you don't need to worry about surges, but batteries contain a lot of energy and a short-circuit can have catastrophic consequences. Fuse your power lines and be extra careful with any exposed leads or connections!
Sep 11th 2015, 17:28

DV1UBY

Joined: Jan 3rd 2015, 19:35
Total Topics: 0
Total Posts: 0
Meaning i need to connect the hf/vhf radios directly to batteries, take note of the polarity without any circuit protection aside from having fuses in the connect leads? I saw a locally made battery...a deep cycle type:
SOLARMASTER - DEEP CYCLE BATTERIES

Description

The solar power battery is designed specifically for solar power installations, particularly those in which it is desirable that maintenance be kept to a minimum.

Application

microwave stationsradio repeatersany remote or hard to reach installationany renewable energy installation

Product
Feature

Longer discharge period and a lower discharge rateUse of thicker, high-density platesExcellent cycling capability because of thick lead-antimony gridsHeavy duty glass-mat separators resisting plate corrosion and increasing battery life

Is 200AH is enough for heavy radio user like me?
Sep 11th 2015, 18:40

W1VT

Super Moderator

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
http://elecraft.365791.n2.nabble.com/K3-AGM-Battery-recommendation-for-K3-td7566351.html
W6ODJ says a 35 AH battery will last 5 hours--so one might expect 200AH to last 30 under similar usage.

You might measure your radio during transmit--if it draws 25 amps, it will draw down 200 AH in 8 hours. If the duty cycle is 25%, That gives you 32 hours. But then you need to factor in the receive drain, which shortens that 32 hours.

With some radios, you can only draw the battery down to 11 or 11.5 volts before the radio distorts, so you may only be able to draw 100 or 150AH. One way around this is to use a battery booster, or switching converter, to keep the voltage up. This can degrade receive by adding noise.

Zack W1VT

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