W2XC - Dentron - Clipperton-L Notes

My personal Clipperton-L notes - some fact / some opinion - but always accurate (hihi):

Path: Home > Dentron Clipperton-L > Clipperton-L Notes

Pros:

A lot of power out of a relatively compact, lightweight package (about 50 pounds).
Inexpensive tube replacement - Chinese 572B's work great and can be had for about $200 for the whole set of four (4).
Operates on either 120 or 240 VAC power supply is built in.
A lot of "bang for the buck" as amplifier will output in excess of 1KW and are still plentiful & inexpensive.
Low profile - the four (4) 572B tubes are mounted horizontally - so entire unit is only 6 3/4" high (including the feet)
572B's are correctly mounted for correct filament alignment.
As of this writing (2011) units are around 30 years old (not quite as old as most of the Heaths and 30L-1's floating around).

Cons:

No longer in production
Not exactly stellar construction.
Stock unit suffers from 60 Hz. hum due to improper feed of directly heated cathode 572-B finals. Output is actually modulated by the AC filament power (no transformer center tap). Dentron pushed the cost cutting envelope too far in this design - BUT - an easy fix. Modification highly recommended and should only cost about $20.00.
NOT tuned input - designed to be driven with tube output exciters. My unit has a broad band matching input board - modern rigs will drive with a tuner. Very late versions of this amplifier had tuned input circuits for each band (rare - not many were produced).
Not designed for continuous modes OR continuous duty. I have had many QSO's running AM - BUT - I kept the plate voltage in the low voltage "CW" position and ran no more than 100 watts output (roughly 330 watts input).
Fan is noisy and constantly changing speed due to series feed through a resistor.
Be VERY careful when buying a Clipperton-L - many ended up on 11 Meters over the years. Be prepared to spend some extra money and time after purchasing one of these amplifiers (for filter caps, fan, mods. & probably a set of final tubes). Also, many of these amplifiers have been abused and now have soft finals.
Low output on 160 Meters due to pi-network coupling to the enclosure - see VE3NH for data.