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Reviews For: Astron RS-12A

Category: Power Supplies

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Review Summary For : Astron RS-12A
Reviews: 9MSRP:
Continuous Duty (Amps): 9

ICS (Amps): 12
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
AI6VN Rating: 2019-04-03
Shorted transformer after 18 months Time Owned: more than 12 months.
I purchased it new from HRO 18 months ago to power a rack of rural SDRs which draw about 6A. After a two day power outage last month it wouldn't come up. I found it blew the line fuse and after opening it find the primary lead of the power transformer is shorted. It probably isn't[t worth replacing the transformer, it will go to the junk pile ;=(
N8FVJ Rating: 2015-12-19
Solid High Quality Design Time Owned: 0 to 3 months.
This review is the RM-12A linear type power supply that is a RS-12A with a volt-ampere meter.

The power supply makes use of a power transformer with a large IE lamination core and heavy gage #12 secondary winding. It is estimated at 350 VA CCS duty or handily capable of the 9 amp continuous, 12 amp 50% duty cycle. Idle current does not heat the core. It is well designed for todays 12--125 volt primary voltage.

The rectifier is a bridge type that is more efficient vs full wave-center tap design with regard to transformer AC to DC conversion efficiency.

The filter capacitor is a computer type screw terminal rated at 16000uF @ 25 volts DC. The ripple current rating of the capacitor is more than adequate for the application. Some other power supplies are deficient in this regard.

The regulator board is a proven design and incorporates over-current & over-voltage protection for your expensive ham radio equipment.

The large heat sink makes use of a pair of matched 2N3771 NPN power transistors. 'El Cheapo' power supplies use the lower rated 2N3904 power transistors. The pass transistor design is more than adequate for 12 amps output at 50% duty cycle. For example, the higher amperage capacity Astron RS-20 uses the same pair of 2N3771 transistors.

The 120 volt AC line input makes use of a noise limiting capacitor and a G-MOV to protect down stream components from 120 volt AC line spikes.

Capacitors are installed on the output terminals and the regulator board for RF protection. A zener diode on the regulator board protects the voltage regulator integrated circuit from voltage spikes.

The dual scale volt-ampere meter is accurate as compared to a digital volt & ampere meter. As accurate as the resolution of an analog meter needle width allows.

The RM-12A output voltage has less than 5mv 120Hz AC ripple at full output or simply an extremely quiet (low noise) power supply. No RF content was measured thus assuring no artifacts superimposed on a HF thru UHF spectrum that can interfere with sensitive receivers.

The physical construction is top rate. Fit & finish is excellent. The power supply & transformer mechanical design operates quietly with just barely perceptible low noise AC hum by placing my ear 1" from the exterior case.

I consider the Astron RS-12M a highly refined power supply and a bargain price wise. Highly recommended.

W0EAJ Rating: 2012-07-11
Pretty Good, but with QC items Time Owned: 0 to 3 months.
I've always liked the ASTRON p/s. Except for a couple I've fixed, they're anvil-solid and reliable. Yesterday, I picked up an RS-12A for a commercial application, and when I opened it to add the special output cord, I noticed they've gone to nearly ALL pop-rivets. The xfmr was wobbling around, as the PR's WERE NOT TIGHT. I had to drill out 2 of 'em and replace with hardware as the excess spacing was making a mechanical hum from the xfmr to the chassis - loud. Also, the binding post nuts were LOOSE. Kinda poor QC, I think - not what I've come to expect from them.
AB0KD Rating: 2011-09-30
Problem free operation Time Owned: more than 12 months.
Problem free since 1982 when purchase for use with an IC-22U. It is the main supply for the 22U and since the mid 2000s an FT-817 and occasionally a TH-D7A and TM-D700A.
W6TH Rating: 2007-12-17
Awfully great Time Owned: 6 to 12 months.
Yes, thought I would say awfully great as the RS 12A is a great performer as I have two of them. Works great with my Icom IC V8000 with full 65 watts output. I also have others including the RS 20M. All have the 10K resistor modification for battery loaf and protects the LM723 voltage regulator. Should any need repair, they are easy to repair and a surplus of parts along with page after page of repair information.
WN7L Rating: 2007-07-31
Can't beat it! Time Owned: more than 12 months.
I have operated my RS-12A since 1975. Do they ever give up the ghost? I have used it to power 2 meter rigs for much of the time I have owned it. I expect my Astron VS-35M to last just as long, but I won't be able to verify the outcome since it is in its first year of operation and I am in my 65th.
KA2RVO Rating: 2006-07-16
20 years old and still working Time Owned: more than 12 months.
It's over 20 years old, does it's thing and never gives me any trouble.
K5YC Rating: 2004-04-15
BUILD LIKE A TANK! Time Owned: more than 12 months.
have been using one now for 12 years. No trouble.
Just sits there and does its thing. Don't ever
worry if it will work or not. I placed a small
muffin fan behind it to stay cool, but really
not needed. I run a CB, police scanner, and other items on the supply. Tried other brands
but for the best use Astron.
WR2W Rating: 2003-05-18
A Solid Good Performer Time Owned: more than 12 months.
I use the RS-12A for my Cobra 148-NW-ST CB radio with not problems. I heard that, hi hi, but I still have non-ham friends I talk to on CB. The only thing I don't like is the plastic screw type power cord terminals. They should be checked for tightness once in awhile as they seem to loosen probably from the slight PS vibration. They are hard to hand tighten because they are mounted soo close to the heat fins on the rear. To use a pliers would probably break them.