WVIP AM 1310 Mount Kisco, NY
October 18, 2002

(Jim Hawkins Radio and Broadcast Technology Page)

Thanks to Peter Polanco for inviting me to take these photos
before the facility is rebuilt and the Collins Model 21-E is removed from the site.

Collins 21E

Driver Cabinet, Power Cabinet and Power Amplifier Cabinet

From left to right, Audio and RF Driver Cabinet, Power Supply Cabinet, and RF Power Amplifier and Modulator Cabinet.
Power Supply Cabinet: Mercury vapor rectifier tubes (replaced with plug-in solid state diode modules)
All units have their relay controls inside the bottom panel.

From Manual: Controls description diagram.

Driver Cabinet

Final Amplifier
and Modulator cabinet

On RF Power output cabinet:
PA Loading, Plate Tuning
Grid Tuning

Tube Compliment For the 21E




1 6AU6 Crystal Oscillator
1 6SJ7 Buffer or Multiplier
1 807 Amplifier
2 4-125A Driver
1 3X2500A3 Final Amplifier
2 6SJ7 Audio Amplifier
2 4-125A Driver Amplifier
2 3X3000A1 Modulator
1 5U4G Exciter Bias
2 866A (Replaced with Solid State Diodes) Final Amplifier Bias
2 866A (Replaced with Solid State Diodes) Low Voltage Plate Supply
2 872A (Replaced with Solid State Diodes) Intermediate Plate Supply
6 575A High Voltage Plate Supply

From Manual:
Bottom of cabinet on the left shows cooling blower for modulator and final tubes. Top shows enclosure shield for output network.

Top of cabinet on right shows enclosure shield for audio output network.

View of transmitter building and antennas.

Driver RF Chassis on left.
Audio Chassis on right.
Cooling fan for power supply
RF Amplifier choke, fixed
capacitor and variable vacuum

Chain couplings for
controls. I don't know
Solid state diode modules,
that replace the mercury
vapor tubes. (No exciting
flickering to watch!)
5KW Harris SX-5 transmitter,
that replaces the 21E.
I was told at this writing that
it will become the Aux and be
replaced by a Nautel

Two views of 3X3000A1 Modulator tubes. 3X2500A3
One of two, Final
tubes behind
tuning and loading

Two views of area in back of Collins

Power Transformer

3 Phase HV Plate transformer
View from above.
 3 Phase HV Plate transformer
3 Phase 208 or 230 V Delta Primary
3 Phase 3910 V Wye Secondary

Generators Roaching Out, Outside

Work Shop

Latitude: 41° 11' 37.4" (41.1937°) north
Longitude: 73° 44' 20.5" (73.739°) west

Collins 21E Manual (pdf) For lots more information.

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