Power Supply Repair

Power Supply Repair

How to repair a switching power supply like those used in DVD players, satellite receivers, VCRs ect. They are all very similar in design, if you can fix one, you can fix em all. Learn from a retired expert in the field.

WARNING: RISK OF ELECTRIC SHOCK EXISTS WHEN WORKING ON ANY ELECTRONIC EQUIPMENT. UNLESS YOU UNDERSTAND SAFETY PROCEDURES AND ARE FAMILIAR WITH ELECTRICAL WORK DO NOT ATTEMPT TO SERVICE YOURSELF

Astron RS-35M Power Supply Unboxing

Astron RS-35M Power Supply Unboxing

ASTRON RS-35M power supply humming

Try to problem solve with an ASTRON RS-35M power supply humming.

I have noticed an Astron RS-35M a Humming. So I have three 2 models RS-35M and one RS-20 and only one has the hum I think on one ... But the other is never powered on.

ANSWER :

Astron RM-50A Modification

Astron RM-50A Modification

ASTRON RS-35M POWER SUPPLY REPAIR

ASTRON RS-35M POWER SUPPLY REPAIR

1000+ Watt 13.80 Volts DC 75 Amp HAM CB Power Supply, 12v 12, 9-14 volt variable

US $179.00

Astron 35 a Humming

Astron 35 a Humming

Is there any cure for the audible humming noise coming from an Astron 35 power supply. I vaguely remember an article about people tightening down the transformer to the chassis to solve this problem, though, I could be wrong.

Astron 35 amp power supply made into 90 amp

Astron 35 amp power supply made into 90 amp

DC 100V 10A Voltmeter Ammeter Blue + Red LED Amp Dual Digital Volt MeterA meter

DC 100V 10A Voltmeter Ammeter Blue + Red LED Amp Dual Digital Volt MeterA meter

Lots of good videos on Youtube describing this item but here is a simple connection tutorial. A prelude to other projects coming soon. One thing will connect to another to make a whole.

ASTRON RS-35A Power Supply Repair

ASTRON RS-35A Power Supply Repair

Astron RS-35m

Astron RS-35m

Astron Power Supply - Astron RS-35M power supply

Astron Power Supply -  Astron RS-35M power supply

Power Supply Hum - a hum after it has been running for a while....

I have an Astron RS-35M power supply that supplies the correct voltage to my equipment but has a hum after it has been running for a while. Would the problem be in the transformer and how would I test it? I have not had the cover off yet.

Answer

Astron RS-35M Power Supply for HF radio

Astron RS-35M Power Supply for HF radio

Bad astron power supply?

Bad astron power supply?

Fixing My Astron Power Supply

Fixing My Astron Power Supply

I have two Astron power supplies for the shack, an RS-35M (the one with the meters) and a RS-35A (with no meters.)  The 35M powers the main rigs, transverters, and accessories.

The 35A was slated to power various VHF and UHF power amplifiers as I bring them on-line.  I bought it used and it started to have problems almost right away. It came up with the correct voltage on the output and could supply a little bit of current (it could run an FT-897 on receive) but as soon as a significant load appears (the FT-897 on transmit) its would cut power.

A little on-line discussion and snooping indicated that it was probably the SCR/crowbar board.  Well, I didn't have a lot of time to horse around with this, so I decided to go for the low-hanging fruit.  I ordered a couple of LM723CNs off of EBay (for a whopping $0.99 shipped!).  This past Saturday I pulled off the cover, removed two bolts holding down that crowbar circuit PCB, and swapped out the LM723 -- happily it's socketed (circled in red).  Screwed the PCB back down, turned on the power supply and Presto!  It's able to put out full current now without tripping the crowbar circuit.