Power Supply For Multiple Radios

[sfreiman]

It was suggested to ditch all the wall warts for my radios and run just a single power supply to cut down on (SWLing) RFI and make things simpler. What sort of specs or brand recommendations does anyone have to run my equipment (listed in my signature, below). Thanks in advance for your feedback.

 

[zz0468]

Astron's are pretty reliable for the price. I prefer the old fashioned kind with a big chunk of iron in it.

 

[DickH]

It was suggested to ditch all the wall warts for my radios and run just a single power supply to cut down on (SWLing) RFI and make things simpler. What sort of specs or brand recommendations does anyone have to run my equipment (listed in my signature, below). Thanks in advance for your feedback.

Tucson and more likely Phoenix should have a surplus electronics store. They should have a variety of computer power supplies that will be well filtered and inexpensive. Most will be 5 volts, too low for most scanners, but there should be other voltages; 6, 9, 12?. If you are handy you can run two 5-volt supplies in series to give you 10 volts. That should work OK for 12 volt inputs.
The store might even have old Motorola or GE speakers that are great for scanners.

 

[kb2vxa]

Sorry Dick, without getting all technical computer PSUs are best left to computers unless you're handy and knowledgeable about modifying them. They're not batteries, you can't wire DC outputs in series without upsetting voltage regulation and invoking the law of unintended consequences.

"I prefer the old fashioned kind with a big chunk of iron in it."
Ditto. Switching supplies can raise hob with receivers, heavy metal is more reliable, easier to diagnose and repair and has the added attraction of maintaining radio silence. As long as it can handle the total continuous load with 100% headroom it will run cool and should last a lifetime, heat is the great destroyer. Oh and BTW future expansion is something to consider, no sense buying a bigger one down the road and wonder what to do with the other one... buy now, prices only go up.

 

[poltergeisty]

How to Convert a Computer ATX Power Supply to a Lab Power Supply - wikiHow

With the main mother board connector, tie both the green wire to the black wire to turn on the PSU. Just plunging in the PSU won't turn it on.

 

[N9JIG]

I ditched the big old Astron for a Samlex SEC1235M switching power supply a while back for several reasons. I power some 2 dozen radios and a dozen or so accessories off the power supply to eliminate most of the wallwarts. If it works on 12VDC it is on the Samlex.

The first reason I ditched the Astron was the heat generation, the Astron 50 amp supply generated so much heat that even in the winter it was boiling in the room. Today it is in the mid 90's here in Illinois and the radio room is comfortably cool, even with 4 computers and 20 some odd radios going. Since I swapped to the Samlex the heat generated has been reduced dramatically!

Second was noise. While the fan on the Samlex kicks on occasionally the Astrons tend to start humming after a while. I have heard this is endemic to large Astrons, and that there is a fix but I didn't feel like fixing it.

The third reason was space. The Samlex is not much larger or heavier than a Uniden scanner yet puts out 35 amps. The Astron was huge and heavy and made for a bear to move around. I added a small shelf under the desktop for the power supply and this helps mask the fan noise and keeps it out of the way. Since there is little (if any) heat generated it works out fine there.

I was worried about RF noise that switching supplies tend to generate but so far I have not had an issue. I don't do a lot of HF work, but even on VHF and UHF there have been no problems.

If the switching supply seems right for you I would make sure I could return it and run it for a week or two to see if it bothers any of your radios before committing to it. I had planned on using this supply at work if it didn't work out for me but it is now my main supply for my shack.

 

[DickH]

Sorry Dick, without getting all technical computer PSUs are best left to computers unless you're handy and knowledgeable about modifying them. They're not batteries, you can't wire DC outputs in series without upsetting voltage regulation and invoking the law of unintended consequences....

What's to modify except perhaps the power input and the output wiring. Pretty simple stuff if one is at all knowledgeable. As for two in series it could be problematic, but it has worked well for me in a couple of instances.

 

[zz0468]

Switching supplies have their advantages... they're smaller, lighter, more energy efficient, etc. But in comparison to heavy iron linear supplies, they seem to have reliability issues. In the large systems I've maintained over the years, I'd say the failure rate runs 20:1 in a comparison of switchers to linear supplies. Or worse. When the choice is mine to make, I don't use a switching supply.

 

[Thayne]

Switching supplies have their advantages... they're smaller, lighter, more energy efficient, etc. But in comparison to heavy iron linear supplies, they seem to have reliability issues. In the large systems I've maintained over the years, I'd say the failure rate runs 20:1 in a comparison of switchers to linear supplies. Or worse. When the choice is mine to make, I don't use a switching supply.

I agree; another reason is that they can fail in a manner that can put an overvoltage on the output--thus possibly blowing up a radio.
Unless whatever the load is constantly draws more than 3 amps I use a 12V12AH gel cell battery kept charged by a 4 amp power suppy/charger like they use for alarms or cameras, then you have an emergency supply if the juice fails, and the battery will also have enough capacity for running a mobile radio for short duty cycle transmitting--and the best thing is that it can all be bought for about $50