why should you not transmit while in the charger?

supernova87a · Post by **supernova87a** » Tue Feb 04, 2003 9:09 pm

I have read in various places that you shouldn't transmit from a handheld when it's in the charger. Why is this?

Monty · Post by **Monty** » Tue Feb 04, 2003 9:23 pm

HI:

In simple terms:

1. Turn Radio OFF while in the Charge process

2. DO NOT ever TRANSMITT while the Radio is in the
charger.

The main reason is the [ Charger ] is not designed
for the current requirement when the radio is in transmitt.

The [ ONLY ] exception is a SVA or a Mobile Charger
designed for it.

You could damage both the radio, and the charger
depending on the state of either.

The problem is the charger again does not have
the current capicity or the voltage regulation.

When a HT goes into transmitt, it can sometimes draw
1 ~ 2 Amps, and the surge current is even higher. This
may look like a direct short as far as the charger is concerned.

Some chargers are { smart } and will either Crowbar off,
or just blow the fuse if a shorted battery is inserted, or
to much current is being drawn

In anycase, it best to read the instructions and follow
them for your particular charger and radio.

If you want to use your HT as a Base Station, get a
battery Eliminator, and run it off a good 12VDC
Power Supply so long as your radio has that accessory
option

Monty

bernie · Post by **bernie** » Tue Feb 04, 2003 10:21 pm

My two bits worth:
I have seen this done, and repaired the radio after.
All is well, until the battery, being constantly on charge opens.
Then there was about 24 Volts on the radio.
This fried most of the silicon parts.
HTs are not bases anyhow.

Bill Rogers · Post by **Bill Rogers** » Wed Feb 05, 2003 4:12 am

Hi Guys. What about leaving the radio in receive while in the charger? Bill

Post by **wavetar** » Wed Feb 05, 2003 6:11 am

Bill Rogers wrote:Hi Guys. What about leaving the radio in receive while in the charger? Bill

If it's a rapid charger, there's generally no problem, other than the radio taking a little longer to reach 80-90% capacity (generally when the light on the charger turns green). But, you'll never reach 100% capacity, as the radio draws as much or more current than the top-off charge. So, it's not good for the battery in the long run.

Of course, you should never leave the radio ON while in a trickle charger, for the above reason. Depending on the trickle charge rate, the battery will either take forever to charge, maintain it's charge level, or possibly even lose charge. And of course, as is generally the case in these scenarios, the radio gets left in the charger all the time, the cells overheat & the battery deteriorates quickly.

Todd

Susan157 · Post by **Susan157** » Wed Feb 05, 2003 6:48 am

Lets give an example of one motorola
portable.

The Mt1000 5 watt vhf.The battery is a 1100ma.

Ok lets do some of the math.

With the radio on and no rx
60ma. draw
2:radio on with rx 160ma draw
3:radio in tx
1600ma. draw (with good batt)

The"eight hour battery" 5-5-90 rule (1100ma)
23 mins tx, 23 mins rx, 7.2 hours standby on=8 hours

Use the 10% voltage rule for max. batt life.

We teach batteries and antennas to all our search & rescue
personnel.This makes a difference.We use the 2200ma battery

A slow charger will not charge a very low battery
with the radio left on.A fast charger will charge the battery.

When the battery is fully charged, a slow charger will keep
a battery charged if the radio is turned on after the charge but
only if there is not a lot of 160ma traffic each day.The fast
charge does not care.

"Listen in the charger but
"DO NOT TRANSMIT"Do not keep the radio in the charge for
more than three days at a time .This is hard on the life of the battery.

Keygun · Post by **Keygun** » Wed Feb 05, 2003 7:32 am

supernova87a wrote:I have read in various places that you shouldn't transmit from a handheld when it's in the charger. Why is this?

Rapid-chargers for example, are charging the battery with a (much) higher voltage, than the radios/batterys usual voltage. This can cause problems to sensitive radios. That`s why i switch off every radio during the charging process.

Keygun

supernova87a · Post by **supernova87a** » Wed Feb 05, 2003 10:28 am

so, when I want to receive while I have a charger around, can I take the battery completely out and just run the radio from line? this seems like it would avoid the whole battery issue?

nmfire10 · Post by **nmfire10** » Wed Feb 05, 2003 11:22 am

supernova87a wrote:so, when I want to receive while I have a charger around, can I take the battery completely out and just run the radio from line? this seems like it would avoid the whole battery issue?

Line?

supernova87a · Post by **supernova87a** » Wed Feb 05, 2003 11:24 am

as in 12V dc charger line

Tom in D.C. · Post by **Tom in D.C.** » Wed Feb 05, 2003 11:52 am

Supernova87A:

Besides what's been said above, this is...

...definitely not a good idea. The "DC" which some chargers furnish can be pulsating DC, not well filtered or smoothed. Your radio, in either T or R mode, expects pure DC, and this is what the battery gives it. If you're not up on how power supplies and chargers work you should dig into the theory involved and what I've said will become more understandable.

Tom, W2NJS
...in D.C.

(Sorry I incorrectly addressed this post in the first version.)

nmfire10 · Post by **nmfire10** » Wed Feb 05, 2003 12:59 pm

I don't think the radios runs on 12v anyway. Basiclly, you have three choices.

Put it in the charger and turn it off

Get spare battery. Charge one while using the other

Get a real battery elimnator and use that while charging the battery.

Actually, choice "4" would be using a convertacom.

supernova87a · Post by **supernova87a** » Wed Feb 05, 2003 3:22 pm

The thing is, if I pull the battery out, and plug the radio in to the charger, it seems to receive ok. Is this a bad idea?

nmfire10 · Post by **nmfire10** » Wed Feb 05, 2003 5:56 pm

I'm lost now. That doesn't make any sense. Plug what into where???

But anyway, the answer regardless of what funky arangement you have is NO. Lets make this really easy.

DO NOT POWER THE RADIO WITH ANYTHING BUT THE BATTERY OR A BATTERY ELIMINATOR. Period. End of story. There is NO OTHER WAY to do it anyway. I don't understand this "plugging the radio in" thing, they don't do that.

W4WTF · Post by **W4WTF** » Wed Feb 05, 2003 6:07 pm

What kind of radio is this???????

I cant think of any /\/\ stuff that you can plug in, but stuff like my VX-5R will and the interenal charger will charge the battery.

Post by **wavetar** » Wed Feb 05, 2003 6:39 pm

The SP10/SP21/TS21/Spirit Pro/etc, line of radios have a charger which plugs into the accessory mic port to charge the batteries, although I don't think that's what he's talking about.

Todd

Nand · Post by **Nand** » Wed Feb 05, 2003 7:11 pm

Susan157 · Post by **Susan157** » Thu Feb 06, 2003 8:02 pm

We use rapid chargers 95% of the time.

We have not lost a radio because
it was on in the charger.We train the
people how to use the radio in the charger.
Training saves a lot on equipment repairs.

why should you not transmit while in the charger?

why should you not transmit while in the charger?

Radios in a charger "power"

Re: why should you not transmit while in the charger?

Running radio directly off the charger...

Never Lost a Radio or Battery When done correctly.