Upgraded Drake L-4PS Power Supply for L-4,
L-4B, and L-7 Linears
Being offered for your consideration is an
upgraded/refurbished Drake L-4PS power
supply that can be used with the L-4, L-4B,
and L-7 linear amplifiers. It is currently
wired for 220 vac but can be rewired for 110
vac. Test data showed it had 2,500 vdc
output in the SSB position and 1,800 vdc in
the CW position per mode settings on an
amp; voltage readings were measured with
an external Triplett VOM. Works fine with
my L4B and L7 amplifiers.
Upgrade includes over $150 of new parts:
Heathkit Shop power supply board.
Capacitors (330 mfd) with 50% more capacity
Capacitor equalizing resistors.
1,000 volt 3 amp rectifiers (unlike 600 volt 1
Diode equalizing resistors (not used in all
5 K 20 watt ALC resistor (unlike 7 watt
50K 50 watt bleeder/ALC resistors same as
0.82 ohm safety resistor.
Oversized rubber feet for improved air
circulation even on carpet.
Carrying handles for improved portability.
Internal fan for lower component and case
20 amp 220 vac power plug.
Please note that this power supply contains
lethal high voltage. If you are not familiar
with how to use it safely, please do not buy
This item is for sale and shipment in the
lower 48 states only; I cannot ship elsewhere
under any circumstances. Since I'm not a
dealer and have no control over how this
power supply might be used or misused, I
cannot offer any warrantees, returns, or
refunds of any sort; the power supply is
being sold as is and I have made every effort
to honestly describe its condition. My 100%
positive feedback on Ebay is indicative of my
integrity. Please feel free to email me if you
have any questions. Payment should be sent
via PayPal or with a USPS money order within
three days of commitment to buy. FedEx or
UPS will be used as the shipper and I will
double box and purchase adequate
insurance. The power supply alone weighs
43 pounds and double boxing with packing
could add another 7 lbs so shipping is
significant no matter where you live. Last
L4PS, not working properly and not including
all of the upgrades cited above, sold for over
$532 on Ebay as of September 25, shipping
was extra. Price reduced to $425, shipped and insured to your door, lower 48 states only.
Thanks for reading the ad.