[Boatanchors] 'Stoopid' OT question

[Phil]

Hi,

Right now I have a Samlex SC1223 12V switching PS on the bench.  It was 
used on one of the remotes for the club W6BXN repeater system.  Anywhoo, 
it failed, blowing he primary fuse.  Samlex was nice enough to send me a 
.PDF file of the schematic.  Found the output switching transistors 
(2SC3320) are both shorted.  No problem, they're readily available at 
reasonable cost.  Over the past 60+ years I've repaired a gazillion 
power supplies, but not a lot of experience with the switchers, hence 
the question.

This unit has three 2200uF 25V Caps for filtering of the 12 Volt line.  
Two in parallel right after the rectifier and a third after some filter 
chokes.  The two parallel units are "bulging" at the top, it appears 
that luck was with us and they didn't blow their guts all over the 
inside of the unit.

My plans call to replace them along with the transistors, I'm just not 
sure of one thing.  In a switching supply (runs at 25kHz), do I need to 
order some special "Low ESR" 'lytics, or will everyday run of the mill 
2200uF 25Volt 'lytics do just fine???

-- 
73 From "The Beaconeer's Lair"
Specializing in DXing NDBs (Longwave Beacons)
Phil, KO6BB,  http://www.qsl.net/ko6bb/
KO6BB/B beacon, ~20W on 28.290 MHz, Ringo Vertical

HF/LF RADIOS:
HOMEBREW:   7 Tube+Rect 1v3 Regen RX for LF (built 2015)
Icom:       IC-7200 Xceiver, DSP IF & filters (~2015).
Kenwood:    TS-450SAT Xceiver, cascaded 250/125Hz Inrad filters.
10M Beacon: 2 x Realistic HTX-100's on 28.290MHz
SDR:        Softrock Ensemble II LF (built from a kit 2017).

ACC:   HOMEBREW  LF-MF Pre-Amp, 8Hz Audio Filter.
        HOMEBREW  4 Port Antenna Multicoupler, Feeds 4 RX's.
        
ANTENNAS: 88 foot Long Ladder-line fed dipole, 35 feet AGL for MW/SW.
           Active Mini-Whip, 36 Feet AGL for LF/MW/SW.
           37 foot "Low Noise Vertical", 11 feet AGL for LF/MW/SW.
           Cushcraft AR-10 Ringo Vertical, 14 feet AGL for 10M beacon.
Merced, Central California, 37, 18, 37N   120, 30, 6W CM97rh


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