[ICOM] Re Icom T-90a

[Gary Fiber]

The T-90A will draw up to 2 amps during TX and at full receive volume 220 
mA. The wall charger will not supply enough current to properly operate the 
T-90A.

Under External power operation on Page 16 of the instruction manual of the 
T-90A manual states you need to supply 5.5 to 11.0 Volts DC and never over 
11.5 volts DC for safe external power operation.

The CP-19 has built in regulation to supply proper operating voltage to the 
T-90A when supplied with external voltages of 11.5 to 16 volts DC. I don't 
have one here so i can't tell you exactly what voltage is supplied from the 
CP-19. If less than 11.5 volts external power is applied,  the T-90A will 
operate from the internal battery pack not the desired external power.

Hope this helps.

Gary K8IZ


At 08:40 PM 10/22/2004, you wrote:
>GOOD QUESTION - I have wondered the same thing.
>
>The BC-139 Rapid Charger which will charge the battery in 2.5 hours and has
>the CAUTION "To avoid damage to the transceiver, turn the transceiver OFF
>while charging" (Page 5 in the manual).
>
>External power operation can be done.  "An optional CP-19R cigarette lighter
>cable can be used for external power operation" (Page 4 and 5 in the
>manual).  This will charge the battery also.  This is the most practical
>solution.  The second solution I had considered is to purchase the rapid
>charger and a second battery pack now that the prices have come down.
>
>The question originates in that there is no reference about whether or not
>you can operate the radio while the wall charger is connected (Page 4 in the
>manual).  The voltage indicated on the radio while the wall charger is
>plugged in and the radio is then turned on is 11.2 volts.  If someone who
>has a cigarette plug cable will tell us the supplied voltage shown on the
>radio at power on while using the cigarette lighter cable, we will have the
>answer.  If the voltages are the same it should be SAFE to operate the radio
>BUT, the wall charger may not be able to supply the current for transmit,
>CAUSING (1) The radio may cut off the charger and use the battery during
>transmit if the current supply is too low, OR (2)(More likely) It may simply
>may NOT transmit or transmit with low power (or try to and this condition
>may be dangerous to the radio) because the current supply available from the
>wall charger is too small.
>
>Before I try to transmit or even receive for any amount of time, I would
>like to know the voltage shown when turning on the radio while using the
>cigarette lighter cable.
>
>Thanks, es 73, de Jim KG0KP
>
>----- Original Message -----
>From: "Gary Fiber" <g.fiber at verizon.net>
>To: "ICOM Reflector" <icom at mailman.qth.net>
>Sent: Friday, October 22, 2004 9:04 PM
>Subject: Re: [ICOM] Re Icom T-90a
>
>
> > Its unlikely the charger will power the T90A properly. Yes it might for
> > receive but not for transmit. Even when receiving you need to look at the
> > current draw of the T-90A and the current output of the charger. You would
> > probably be best to connect it to a regulated higher amperage power
>supply.
> > I have not looked but would think a nice 12 volt supply will do the trick
> > of some 3 amps or more.
> >
> > Gary K8IZ
> >
> > At 06:58 PM 10/22/2004, you wrote:
> > >The Icom T-90a handheld takes about fifteen hours to fully charge the
>battery.
> > >Is it permissible to use the unit while the charger is plugged into the
> > >wall and
> > >connected to the T-90a or must you leave the unit turned off until the
>battery
> > >is charged? Understanding, of course, that using the T-90a while the
> > >battery is
> > >being charged will cause the charging process to take longer.
> > >
> > >Thank you.
> > >
> > >Duane Fischer, W8DBF
> > >dfischer at usol.com
> > >
> > >
> > >----
> > >Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> > >Icom Users Net: Sundays, 1700Z, 14.316 MHz
> > >Icom FAQ: http://www.qsl.net/icom/
> >
> > Gary Fiber K8IZ
> > GROL PG-19-6691
> > Washington State Resident
> >
> >
> > ----
> > Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> > Icom Users Net: Sundays, 1700Z, 14.316 MHz
> > Icom FAQ: http://www.qsl.net/icom/
> >
>
>
>----
>Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
>Icom Users Net: Sundays, 1700Z, 14.316 MHz
>Icom FAQ: http://www.qsl.net/icom/

Gary Fiber K8IZ
GROL PG-19-6691
Washington State Resident