Wiring Required for an iCom CP-20 12v to 11v Power Source

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garich
Posts: 8
Joined: Mon Jul 07, 2014 1:01 pm

Wiring Required for an iCom CP-20 12v to 11v Power Source

Post by garich » Wed Oct 11, 2017 7:33 pm

Hi All, we are in the process of replacing our trusty iCom A4 handheld radio with the 8.33 compliant A6e. The A4 was a straight forward 12v dc affair but the A6e has a requirement for 11v and comes with a 12v to 11v dc power source. We have a 12v 7ah battery trickle charged off a solar panel which quite happily powered our intercom and radio setup before but while the CP-20 will power the A6e in RX mode it fades to nothing in TX mode.

Has anybody experienced a similar problem?

Any thoughts much appreciated.
Garic Howles
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John Price
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Joined: Mon Jan 07, 2008 7:27 pm
Location: Eynsford

Re: Wiring Required for an iCom CP-20 12v to 11v Power Sourc

Post by John Price » Thu Oct 12, 2017 12:20 pm

How old and what type of battery.

John.
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garich
Posts: 8
Joined: Mon Jul 07, 2014 1:01 pm

Re: Wiring Required for an iCom CP-20 12v to 11v Power Sourc

Post by garich » Thu Oct 12, 2017 5:42 pm

Hi John, the battery is only a couple of months old and is a yuasa 12v 7 ah sealed unit.
Garic Howles
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John Price
Posts: 189
Joined: Mon Jan 07, 2008 7:27 pm
Location: Eynsford

Re: Wiring Required for an iCom CP-20 12v to 11v Power Sourc

Post by John Price » Fri Oct 13, 2017 8:18 am

I think from memory that the power module works from 11-24v ish!

It'll either be a DC to DC regulator or a constant power regulator I think the former is more likely.

Because you are at the bottom of the working band when in transmit, the voltage drop may be a little to near the cut off thus the fade.

If you give I COM a ring they may tell you the voltage range of the A6E and it may be possible to operate the hand held without the CP-20.

If you find a 6v battery, connect them in series, and you could try a test at 18v to test this out.
Don't forget to add a fuse.

The CP-20 is used to be inserted into a cigarette lighter and the voltage there is normally at or about 14v due to the alternator charging the battery.

John.
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garich
Posts: 8
Joined: Mon Jul 07, 2014 1:01 pm

Re: Wiring Required for an iCom CP-20 12v to 11v Power Sourc

Post by garich » Sun Oct 15, 2017 8:20 pm

Hi John,

Many thanks for your reply. I've talked to iCom, who were v helpful and they recommend insuring that the converter is wired directly to the battery rather than the solar power controller, which is what our current installation achieves.

Wired directly to the battery, the radio works well so I think we'll need to examine the existing circuit and adjust and/or re-wire accordingly.

Cheers,

G
Garic Howles
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