AnyTone AT-5555 Plus (New Version) DC Power Loss

[Recon]

ASTRON 70 Amp power supply set at 13.8 volts. Also connected an external volt meter to confirm 13.8 volts going into the radio.
I set the menu to display the DC Volts when depressing the mic. Depressing the mic indicates 13.6 - 13.7 volts.
Using the radio for two months with no problems. RF Power carrier set at 5 watts. Yesterday as I was transmitting, the Low DC Volt Alarm and Hi-SWR (5) Warning activated and I immediately shut-down. After thirty-minutes, I turned-on the radio, depressed the mic and the DC volts was 12.2 volts. Left the radio on for thirty-minutes and the DC volts was down to 11.8 volts. Any ideas?
My friend had a new AT-5555 Plus (new version) for only two weeks and no transmit. He was fortunate that the seller replaced his radio with a new radio.

 

[9C1Driver]

Check the simple things. Assuming the Astron is fine check the radio power cord, fuse, and connection points. Maybe try a different power cord. After that it would have to be in the radio. Loose connection, bad solder joint, or a failing component.

 

[BC Coyote]

I had something similar happen recently with my 5555N2 and it was the crappy fuse holder. I replaced it with a heavy duty holder and everything went back to normal.

 

[Recon]

I had something similar happen recently with my 5555N2 and it was the crappy fuse holder. I replaced it with a heavy duty holder and everything went back to normal.

I have a heavy-duty / 10 AWG power cord with a 10 amp spade type fuse. Same type power cord attached to Stryker 955.
Tried three power supplies and no change.
Both power cords are connected to the power supply with Ring Terminals.
DC volts gradually decreases without transmitting.

 

[Recon]

I had something similar happen recently with my 5555N2 and it was the crappy fuse holder. I replaced it with a heavy duty holder and everything went back to normal.

I'm using my back-up President Andy II FCC radio until I resolve the voltage problem with the Quad 5, but I have not located the procedure to access the Service Menu to reduce the RF power down to two-watts.

 

[Recon]

Check the simple things. Assuming the Astron is fine check the radio power cord, fuse, and connection points. Maybe try a different power cord. After that it would have to be in the radio. Loose connection, bad solder joint, or a failing component.

Using the process of elimination I removed the amp and no problem.

 

[BC Coyote]

Using the process of elimination I removed the amp and no problem.

Do you mean an amp you were running external to the radio, or do you mean you removed the final PA stage from the radio?
Just curious as you never mentioned an external amp in your original post.........

 

[Recon]

Do you mean an amp you were running external to the radio, or do you mean you removed the final PA stage from the radio?
Just curious as you never mentioned an external amp in your original post.........

Yes, an external amp. 1 X 4 mobile amp matched-up to an Astron 70 Amp Power Supply. I can't identify the problem so I eliminated the amp.

 

[BC Coyote]

I can't identify the problem so I eliminated the amp.

One or more of the amp transistors is shorted internally and that is where all your current and voltage is going. Dud transistor is probably getting very hot so should be easy to figure out which one(s) are at fault. Good Luck with it. Glad it wasn't a radio problem!

 

[Recon]

One or more of the amp transistors is shorted internally and that is where all your current and voltage is going. Dud transistor is probably getting very hot so should be easy to figure out which one(s) are at fault. Good Luck with it. Glad it wasn't a radio problem!

Thank you. After I triple-checked the coax and jumpers and swapped-out the radio with a 1.5 watt hand-held and the problem wasn't resolved, I confirmed that the amp had to be the cause of the problem. As we all know, amp builders do not warranty transistors.

 

[Elliott Hart]

I would not run this radio into a 1 x 4 amp. Too many peak watts even if you turn the dead key of the radio down.

 

[Recon]

I would not run this radio into a 1 x 4 amp. Too many peak watts even if you turn the dead key of the radio down.

Okay, thank you. I'll take your advice. Maybe I should get another radio to use in the garage that will match-up with the 1 X 4, or swap-out the 1 X 4 for a straight 2-pill?

 

[Recon]

Okay, thank you. I'll take your advice. Maybe I should get another radio to use in the garage that will match-up with the 1 X 4, or swap-out the 1 X 4 for a straight 2-pill?

I would not run this radio into a 1 x 4 amp. Too many peak watts even if you turn the dead key of the radio down.

Could that be the reason the amp was damaged?

 

[BC Coyote]

Could that be the reason the amp was damaged?

Pretty much guarantee it. The thing is if you don't have a proper peak reading watt meter you will see less power from the 5555N2 than what it is actually putting out on peaks. It's very easy to overdrive an amp with that radio unless you've gone into the service menu and turned deadkey way way down.

I often run my 5555N2 barefoot and have no trouble whatsoever talking DX. It talks just as well as my 148GTL with a Palomar 200 on it. No need for an amp with that radio if you have a good antenna system!

 

[Recon]

Pretty much guarantee it. The thing is if you don't have a proper peak reading watt meter you will see less power from the 5555N2 than what it is actually putting out on peaks. It's very easy to overdrive an amp with that radio unless you've gone into the service menu and turned deadkey way way down.

I often run my 5555N2 barefoot and have no trouble whatsoever talking DX. It talks just as well as my 148GTL with a Palomar 200 on it. No need for an amp with that radio if you have a good antenna system!

I have two BIRD wattmeters. Model 43 with factory installed PEP kit and a Model 4410 A with a 4410-5 element / slug.
I accessed the Service Menu and reduced the Low carrier down to a 1.5 watt carrier which produces only 20 PEP watts driving the 1 X 4. The amp was working fine for the past two months.