Astron RS-35M Radio Shuts Down

[TonyV225]

.

I will hook up my volt ohm meter just to see how accurate the power supply meter is.

I was gonna suggest the same but see you were on the right track already

 

[Captain Kilowatt]

I thought you got it working??

After you called me I found this to help a bit. Also check the pass transistors. From what you described to me on the phone it sounds different than what the original issue was. Either that or I am mistaken.

Good schematic with added info as to what is going on it the PSU.

http://www.al7fs.us/astron-rs35m%20annotated%203.pdf


More RS-35M info

http://www.google.ca/url?sa=t&rct=j...oxWdFC-hljjae8Q&bvm=bv.43828540,d.dmQ&cad=rja

Check/loosen/retighten all screws holding the PC board as well.

 

[Happy_Hamer]

Just to let everyone know where I am on this power supply.

I changed the IC regulator, hooked up a Kenwood TS-2000 and keyed up the radio and BAM, the radio shut down.

The amp draw meter slammed all the way over to 40 amps.

Hooked up a voltage meter to the power supply and the voltage varies from 12 to 16 volts just sitting there, with no load.

 

[RADIOOMAN]

Just to let everyone know where I am on this power supply.

I changed the IC regulator, hooked up a Kenwood TS-2000 and keyed up the radio and BAM, the radio shut down.

The amp draw meter slammed all the way over to 40 amps.

Hooked up a voltage meter to the power supply and the voltage varies from 12 to 16 volts just sitting there, with no load.

Could the ammeter shunts/current equalizing resistors ( r101 & r102 ) be burnt open?

0.05 ohm 5 watt wirewound
For testing purposes you can jumper them with a wire.
Ammeter will read low and current sharing between pass devices will be reduced.
But you can test it with a radio this way.

 

[Captain Kilowatt]

It slams the meter yet it does not blow fuses is that right? :blink: I can think of a few things that would shut it down even without a load but I just can't figure out the voltage fluctuation issue. It is fast/slow or erratic when it changes? Does it seem to be a smooth and constant change like something is slowly oscillating?

 

[Happy_Hamer]

I will video it on a meter

It slams the meter yet it does not blow fuses is that right? :blink: I can think of a few things that would shut it down even without a load but I just can't figure out the voltage fluctuation issue. It is fast/slow or erratic when it changes? Does it seem to be a smooth and constant change like something is slowly oscillating?

 

[Happy_Hamer]

HAHAHAHA I put a new battery in the volt ohm meter and it sits at a constant 13.04 volts

Stil pegs the meter all the way to the right for amp draw when keying up the TS-2000 and shuts the radio off. No fuses are blown

 

[Captain Kilowatt]

HAHAHAHA I put a new battery in the volt ohm meter and it sits at a constant 13.04 volts

:headbang <can not stand it>ARRRRGGHHH!!!! So many brain cells lost over trying to figure that one out and I don't have any I can spare. :laugh: I was assuming you were using an analog meter!!

Stil pegs the meter all the way to the right for amp draw when keying up the TS-2000 and shuts the radio off. No fuses are blown

OK time to use a resistive load or some lamps instead of real electronic gear. Even just a few amps draw should be enough to determine what is happening under load. Things like does the voltage go to near zero or does it spike and cause the crowbar cct to trip. Save the gear destruction for long winded QSO's.

 

[hookedon6]

HAHAHAHA I put a new battery in the volt ohm meter and it sits at a constant 13.04 volts /QUOTE]


yep, those dead batteries in a VOM WILL kill you<gotproof>

I ALWAYS test the batteries in my Simpson,.... EVERY usage

 

[Captain Kilowatt]

My analog VOM needs no batteries to measure voltage and my digital meters both have a little BATTERY icon that flashes when the battery needs to be replaced.