SABER 1 DROPS OUT OF TX AFTER IT HEATS UP

FDNY · Post by **FDNY** » Wed Dec 12, 2001 2:25 pm

hi,,

i have a saber 1 UHF,,,,after talking for 30-45mins and the unit get hot the radio drops out of the repeater....is this normal for the sbaer,,,or is it a malfunction.........i noticed this when i was transmitting for about 45mins on a repeater.......do you think motorola would be able to fix it and identify the problem

thanks

F.D.N.Y.

radioEd · Post by **radioEd** » Wed Dec 12, 2001 8:07 pm

I'm wondering what your output wattage is? See if you can put a wattmeter or analyzer on the radio? If its set to the max? (whats max. 6 watts, maybe 7 watts Top?) you might want to drop it to 3 or 4 watts!

Monty · Post by **Monty** » Wed Dec 12, 2001 10:49 pm

Hi:

In general, the radio is designed to operate
5-10 Min / 10-15 off.

If you " Keydown" for long periods of time, it possible the Transmitter PA ( and Battery ) will suffer.

If you are long winded, take some advice, and
program one of your channels for Low Power.

That will save you a Blown PA module, and save your battery

Monty

raymond345 · Post by **raymond345** » Thu Dec 13, 2001 2:14 am

How old is the battery.An 1100 ma battery
is a standard for most motorola portables.
The salesman will say this battery lasts for
8 hours.As radio tech's lets do the math.
Gp350 radio at 5 watts. 60 ma. turned on.
160 ma. rec. 1600 ma on tx.
My math said 7.2 hours on , 23 mins. tx and 23 min rx calls in 8 hrs.

5-5-90 is the info from "M" on their
batteries. Most people do not do the math.

Raymond eMail [email protected]

radioEd · Post by **radioEd** » Thu Dec 13, 2001 7:48 pm

Well I have to agree with Monty! (I don't know of anyone talking for even 15 mins without un-keying!) So I wanted a clear picture of FDNY...and how long is his talk time?
And Raymond you also I agree with! I know a few people who got sabers, (from ebay, the guy next store) and were up at 6 watts! Or it could be something else? lets see..

<font size=-1>[ This Message was edited by: radioEd on 2001-12-13 22:58 ]</font>

raymond345 · Post by **raymond345** » Thu Dec 13, 2001 8:42 pm

Battery time is over the 8 hour day
if it is 1 min or 5 mins , total time used in 8 hours.Do the math.In search and rescue
it is my job to have the radio still work.
Train the users. Raymond

radioEd · Post by **radioEd** » Thu Dec 13, 2001 9:47 pm

Well Raymond we have something in common. Its your job & mine too keep the radios working! and since I'm with county radio repair...I cover about 24 departments plus "search & rescue" so I know the math...its plaster'ed all over the wall on a poster. So now we wait to hear from FDNY, & see what his output power is set at? have a good nite!

cracked · Post by **cracked** » Fri Dec 14, 2001 12:50 pm

We've encountered one or two rare saber 1 UHF radios that output over 7 watts. It's a possibility with yours too. Turn it down to no more than 5 watts to save your RFPA and battery life.

Will · Post by **Will** » Fri Dec 14, 2001 3:24 pm

The Saber, better than and like most portable radio transmitters was NOT designed to put up with that excessive transmit duty cycle without getting realy HOT.. The trnsmitter's heatsink was not designed for anything past a 50% duty cycle, if that, more like 10% tx, 10% Rx, 80% standby-cool down!

Rag chewers WILL need a serious chiller on the radio's heat sink!!!!!!

FDNY · Post by **FDNY** » Sat Dec 15, 2001 9:47 am

good afternoon gent's!!!!!!!!!!!..

i use the radio for my personal amateur radio use....my radio runs at about 5watts on high power,,,,i will keep it in the low mode of power...........i figured it was not to be used more then 5 or 10 minutes talk time...............i want to wish all of you happy holday to you and your families and to those who just view this message

take care,,i will continue on bat labs,,great place and great people on here!!!!!!!!!!!!!...........

F.D.N.Y.--THE BRAVEST...

radioEd · Post by **radioEd** » Sat Dec 15, 2001 11:34 am

Good to see you back! Our repeaters have a time out feature. Most all of them are appx: 3 mins.. So we get a roundtable of a few hams, and by the time it gets back to me, 3-5 mins have gone bye. See what the lowest power setting is for you to work your repeater (full quieting) try it out! All ht's heat up at 5 watts, I don't care who makes the radio. there gonna get hot on a long tx. I have other hams here using 200+ to hit the same repeater 30 miles away. That only takes me 3-4 watts to hit full quieting! Ragchewing on 20 meters with the key down for 20/30 mins is ok. since the HF radio has heat sinks, & Fans, to cool her down! Sabers are gonna heat up also, on a long transmit time, and at 5 watts+ .. have a good holiday! 73's Ed